"Mere Sapnon ka Bhaarat" - Suggestions on Telecom Policy

Suggestions on Telecom Policy

1.     World Telecom scenario

World over today, the Telecom business is driven basically by technical innovation – what we call next generation technology. India has the potential to lead the world and show the way. For this, the government has to play its role- to initiate the right policy moves that can leverage networking power to provide the necessary growth in the tottering GDP. The business is not about the old product set but of a new paradigm altogether – of a set of totally new services that transform the way people live an enhanced life style and the way they communicate with each other – that brings about an efficiency hitherto not even dreamt of. This represents a way to empower users through a new infrastructure platform that keeps customers continuously attracted to a variety of newer and newer services offered to them. This capability allows the Average Revenue Per User (ARPU) to continuously increase with time. The next generation networks also represent an opportunity to reduce capital expenditures by being able to offer all services over a single integrated IP based infrastructure. Likewise, the Soft Switch and IMS architectures would extend multi-fold decrease in operational expenses like space, power, air-conditioning, human resource, etc. Implementation of NGN would therefore ensure increased revenue and profitability on an unprecedented scale.

2.     Objective

While acknowledging the rapid changes in the world Telecom scenario, the government can work on implementing policies suitable for India’s operators and service providers to adopt the world’s best practices in terms of technology and management to place India

(a)   among top 10 countries in Internet usage in terms of bandwidth utilization,

(b)   among top 5 countries in terms of number of Internet users,

(c)    and among top 3 countries in terms of number of voice devices (phones & mobile)

in the next five years.

3.     Considering the following limitations and afflictions 

a.   that Indian market for Telecom particularly for mobile services has saturated over the last couple of years, though there is ample scope for its further proliferation

b.   that reach of mobile service has been stagnant especially in vast tracts of rural areas, leading to absence of requisite signal levels thereby defeating the purpose of connectivity

c.  that quality of service in the case of mobile services has fallen to unacceptable levels in terms of frequent call drops and session breakage at cell crossings and that there is need to ensure remedial measures in the interest of mobile users

d.  that today’s market is getting more and more saturated with vanilla type voice services and that today’s customer can be won increasingly through service offerings involving multimedia with information/content delivery in transactional mode by such applications as Social media, WhatsAp, Blogs, etc.

e.   that telecom connectivity is driven dominantly by wireless technologies notably 3G and 4G, but the spectrum allotted to operators are under utilized as the user base has not risen in necessary proportion

f.    that spectrum is a virtual gold mine belonging to the citizen at large, and that lot of unused spectrum allotted to agencies such as TV Broadcasting, and that re-farming of unused spectrum is an imperative and need of the hour

g.   that there is urgent need to implement the Next Generation framework which brings about convergence between fixed and mobile networks, and makes it possible implement the concept of “Any device, Any Access, Any service, Anytime, Anywhere” through communication networks driven dominantly by Internet based technologies on end-to-end basis that brings with it unprecedented reduction in capex and opex

h.  that Optical Fibre Cable (OFC) though laid extensively by various operators, are heavily underutilized resulting in constraining bandwidth availability impacting its price, both in Core and Access networks

i.      that the public sector companies instead of serving as a model for implementation of  government policy are sliding downward in all major targeted parameters

j.     that the huge potential domestic market remains untapped and if developed through orchestrated policy changes that address the aforementioned limitations is bound to position Indian companies to participate aggressively in businesses around the globe,

Following 10-point policy initiatives are proposed for speedy implementation to be able to achieve the stated objectives.

Ref	Policy Action Plan
a	(i)       Tower usage policy to increase transmitter density       (ii)   Usage policy for OFC/copper cables to implement Passive Optical Networks and Landline Networks respectively in Access segment
b	Policy of connectivity mapping to be implemented for monitoring coverage targets
c	Policy of implementing periodic “drive tests” to cover entire licensed area say every two years
d	(i)   Set national target of 10 fold increase in Internet proliferation in 5 years      (ii)   Policy and implementation target for IPv6
e	(i)   Policy of sharing of spectrum between licensed operators      (ii)   Policy for in-building solutions in urban areas      (iii)    Policy for Sharing of multi-frequency antenna systems
f	Identify un-used spectrum and policy for re-farming, utilizing, valuation & public auction
g	(i)   Policy to encourage operators to achieve Yr-on-Yr growth of 60% p.a.      (ii)   Policy for legalizing Voice over IP services over PSTN networks      (iii)    Policy framework for complying with “Any device, any access, any service”      (iv)   Policy for fixed mobile convergence
h	Fair usage policy for Optical Fibre Cables
i	Innovation & professional management only way to revive PSUs.
j	(i)   Policy to encourage Indian operators to participate in International businesses      (ii)   Policy to encourage Indian R&D to enable manufacture of end devices and export to International businesses

4.  Strategic Thrust in policy:

Since the traditional voice and bandwidth services have become commoditized, there is need for operators to rethink their strategy by transforming themselves from voice centric bit pipe connectivity provider to a multi-service platform provider. The vision is that of creating a new service driven organization. The strategy is to create new value curve by converting the bit pipe into a service pipe and to extrapolate the strategic value profile through innovative factors that enable capture of new markets and services. The Year-on-year growth plan in order to match the 10 fold growth in Internet market in 5 years should be targeted at 60%. This growth figure has not been unknown to Telecom segment even during trying times in the last decade, and considering the enormous potential in technology solutions, the figure therefore represents a do-able proposition. There is credible opportunity here to propel other segments of industry in urban as well as in rural areas and help position the overall GDP back to 2-digit figure.  

Improvement in reliability of long distance network has to be taken up on priority with emphasis on convergence in terms of its utilization by different operators. This calls for new initiatives for setting up of managed IP networks. This also calls for centralizing network operating centre at national level by every operator to monitor their respective national level network through single window.

To bring about quality services for the common man, there must be regulatory focus on ensuring proper coverage of services through performance bench-marking and accountability. The creation of GIS Coverage maps for all access technologies. Mobile drive tests will provide accurate coverage picture which is critical in providing quality service to the common man. Strategic partnerships between the operators and NIC (Dept of IT) could leverage the latter’s GIS digital maps in consolidating associated knowledge base.

The mobile offering is witness to ruthless competition, and it is but a matter of time that this sector too will start experiencing the pressures of churn. It is therefore imperative that operators work on increasing the value of their mobile offerings through such concepts as Customer Home Gateway in accordance with the latest GSM standards that connects any device such as phone, TV set or PC through any access to any service. Key services would be voice, high speed internet, WiFi, DTH and/or IPTV.

India’s regulatory framework has an opportunity to blaze a trail in adapting itself to the powerful technological options available today. For instance, it could take bold initiatives in the concept of sharing valuable spectrum between licensed operators. It could mandate the use of in-building solutions in dense urban areas. It could allow tremendous relief to urban clutter by mandating sharing of multi-frequency antenna systems and software based radio systems in such areas. These measures will subdue the needless clamor by operators for leasing additional spectrum.

After the proliferation of TV cable systems and DTH, the TV broadcast spectrum in the 700 MHz band has been left to waste. In the USA, this spectrum band has been envisioned to be utilized for national broadband by ordering the erstwhile broadcasters to vacate the spectrum through an Act of Parliament. The valuation of the said spectrum runs into mind boggling figures. Yet, no serious attempt has so far been made in India to tap this virtual gold mine. The opportunity can catapult the broadband initiatives stated above to success and render the proposed 5-year objective easily possible.

The OFC deployment across the country represents an indispensable asset, put in place by various operators but not utilized optimally. These assets have been created by pooling the resources of a host of public organizations such as the roads authorities, the municipal authorities, etc. and also cause considerable disruption in traffic at the time of installation. It is high time that such activity is brought within the ambit of regulation, so that the resource is not monopolized by any one operator, rather optimally utilized through a fair usage policy.

The Public Sector companies of the government have been known to be subject to government’s interference for reasons other than the valid ones. The existence of these PSUs should not be justified by vague reasons such as security, etc. Rather, the only justification may be that they represent a platform for the government to showcase their policy through early implementation. The PSUs should therefore show the necessary leadership for this purpose, and must therefore exhibit a very healthy financial outlook, the best among the top service providers. They must lead through example. The turn round of the PSUs therefore represents the top priority for government.

Last but not the least, the aforesaid policy initiatives that are meant to create a strong domestic market will afford India to set its sight on participation in the global arena. Policy initiatives to tap technology talent in R&D need to be taken.

Conclusion:

This article is intended to offer suggestions on Telecom Policy to the new government under "Mere sapnon ka Bhaarat", the implementation of which can place India in a leadership role in the comity of nations. The suggestions can be implemented through strong conviction and belief in collaborative brain-storming culture that must be fostered among the various stakeholders by the government. 

NOTE: Being a technical subject, the author has posted several allied articles in this blog that may be able to lend more clarity to a reader who has no prior knowledge of the subject. The reader is requested to refer to these articles and provide valued feedback/comments.

Internet Protocol drives Universal Networking

Internet Protocol drives Universal Networking

Role of Internet Protocol in Networking

When digitalization of networks started taking place in the late eighties and  Integrated Services Digital Network (ISDN) was being developed for supporting data applications, the concept of OSI model came into being. OSI stands for ‘Open System Interconnection’ and the model classifies the entire end-to-end digital application as a set of seven distinct functions layered one on top of the other, each one entirely independent o f the others in terms of development and implementations. The model called for standardization of interfaces between the layers. The 7-layered OSI model is depicted in Figure 1.

Any application comprising of software is ordered in the form of packets of bit-wise information encapsulated in the presentation layer by appending a predefined leading header and possibly a trailing footer, that contain information and parameters pertaining to the presentation function. The presentation function in turn is encapsulated in the Sessions layer in similar manner, and so on until the process reaches the Physical layer. The physical layer defines the bits and bytes that get physically carried from origin to destination.

The Link Layer

The link layer is meant for transporting information between limited numbers of nodes with communication rules being defined at the link level. Here, a link is defined as a connection between a set of neighboring nodes. The communication rules are referred to as ‘protocols’. Initially, the link layer was conceived to serve a local area network within a building or a campus. Over a period of time, ‘Ethernet’ became a link layer protocol that gained tremendous popularity and virtually became a widely accepted standard. Employees in a company working in a common office could access their counterparts at speeds of 10Mbps or 100Mbps. The latter came to be known as the Fast Ethernet (FE). Later on, the concept of local area network was extended to the metro area within a city, where different commercial establishments such as banks or companies scattered at various geographic locations in the city had need for exclusive internal connectivity. The connectivity service provider soon had to contend with huge demand where he had to cater to providing metro area connections to thousands of establishments. There was therefore need to develop another link layer protocol that had to virtually carry the basic Ethernet between such customers. A Metro Ethernet Forum (MEF) was formed for the purpose of defining such services. To be able to deliver these services, the service provider needed to deploy serving nodes close to the customer premises. The function of these nodes would be to aggregate the traffic of different customers. There would then be a need to identify the user organizations. There would be need to control information queues to control traffic. All these set of new rules or protocols that enable these functions came to be known as the ‘Carrier Ethernet’. The new interfaces supported speeds of 1 Gigabit per second (Gbps) and then later on 10 Gbps, which came to be known as 1Gigbit Ethernet and 10Gigabit Ethernet respectively or simply as 1GE and 10GE.

The Network Layer

Consider a situation where one wants to step up one’s communications needs to the global level. In such a case, every node would need to have a global identity and if every such node needed to setup communication with any other node, a network level rule or protocol would be needed globally at the network level. The Internet protocol has turned out to be the most popular network layer protocol accepted by millions of Internet users. Like in the case of the Ethernet, here also, the service provider would need to setup aggregation nodes close to the customer locations that perform network functions such as routing the information packets to desired locations. The mechanism of maintaining route tables, updating them from time to time as per predefined rules and performing the routing functions are defined by standard protocols understood by every router. These nodes when interconnected together to provide any-node to any- node connectivity form a network of IP routers.

Initially, the Internet protocol called IPv4 or ‘IP version 4’ catered to only 2³² addresses which equal nearly 4 billion. Over the period of last two decades, it was realized by the Internet fraternity that this number was too small to cater to the needs of the growing number of Internet users. The Internet standards community called the IETF has subsequently upgraded the protocol to IPv6 or ‘IP version 6’ that caters to 2¹²⁸ addresses – a number which is sufficiently large to comprehensively cater to the needs of all the possible Internet users for a long time to come. The IPv6 protocol also includes a number of other new features that are likely to be needed in the future.

The Transport, Session & Presentation Layers

The Transport layer provides protocols that ensure reliable data transfer between users. The Sessions layer establishes, manages and terminates the connections between users, often referred to as Call control processes. The Presentation layer establishes context between Application Layer entities, in which the higher-layer entities may use different syntax and semantics if the presentation service provides a mapping between them. These layers are in most cases within the domain of the Telecom Service Provider.

The Application Layers

The Application layer interacts with software applications that implement a communicating component. Examples are Common Management Information protocol (CMIP), Hypertext Transfer protocol (HTTP), File Transfer protocol (FTP), Simple Mail Transfer protocol (SMTP) and Simple Network Management protocol (SNMP).

The Applications

On top of the Application layer, we have the specific Application which is visible to the user. The Application software works on the Computer operating system, and as such resides in the memory of the end terminal, say the PC, laptop or the mobile device. There are virtually thousands of applications that are used to drive the Input-Output devices connected to the computing system to deliver different type of services. The Input devices comprise of a variety of sensors such as optical scanners, pressure sensers, and so on, whereas the output devices range from printers, optical light emitting devices, sound producing devices, etc. The applications can be designed to interact with different devices spread anywhere in the network. Development of Applications therefore has become a multi-billion dollar industry where the developer only needs to know the computer programming language to develop the software without ever having to know the complexity of the intervening Telecom connectivity. Application development can therefore become a defining business for the IT professionals in India with enormous growth potential.

IP-MPLS Infrastructure

However, for being able to utilize these applications anywhere in the network, it is necessary to design and implement a network that will support the end user’s requirements in terms of the underlying layers that we described in the previous paragraphs. A Service Provider with an IP backbone may provide VPNs (Virtual Private Networks) which itself provides IP service to its customers.  MPLS (Multiprotocol Label Switching) is used for forwarding packets over the backbone. The BGP (Border Gateway Protocol) is used for distributing routes over the backbone.  The twin goals of this method are to support the outsourcing of IP backbone services for enterprise networks and for back-hauling mobile or broadband traffic. It does so in a manner, which is simple for the enterprise, while still scalable and flexible for the Service Provider, and while allowing the Service Provider to add value.

MPLS technology places labels on IP packets in a router. It categorizes or monitors the packets that traverse different routers in the network. MPLS is an overlay protocol MPLS is not designed to replace IP. Rather, it is designed as an overlay protocol that adds a set of rules to IP so that traffic can be classified, marked and policed.

MPLS-equipped networks use MPLS-aware devices known as label edge routers (LERs), positioned at the network’s edges. These devices are designed to inspect IP packets entering the network and add MPLS headers, as well as removing the headers from packets leaving the MPLS network. Inside the boundaries of the MPLS network, devices known as label switch routers (LSRs) look for an MPLS label on each packet that passes through them, looking up and following the instructions contained in those labels, routing them based on a list of instructions. Thus edge-to-edge Label Switched Paths (LSP) can be configured from one LER to another, through a series of LSRs, across the MPLS network. LSPs are pre-assigned and pre-engineered paths that packets with a certain label should follow without requiring the use of any dedicated lines such as the traditional SDH (Synchronous Digital Hierarchy) links. These are virtual circuits very similar to the circuit-switched paths in ATM or Frame Relay. One of the most obvious advantages of MPLS is that it provides network administrators with a number of tools for traffic engineering. An administrator, for example, can define a LSP that ensures VoIP traffic will be routed through the most reliable, highest performing sections of the network while less critical traffic, such as email, is sent across the slower sections.

Carrier Ethernet Aggregation Infrastructure

The IP Transport network is segregated into two parts –  (i) A Core Layer-3 IP-MPLS based network that covers major cities and hubs in the country connected through DWDM systems through the north side interfaces and (ii) An Aggregation Layer-2 Ethernet based network terminated at the IP-MPLS Edge node. An aggregation network as the name suggests, aggregates traffic over an area of say 100 km radius through a three tier architecture. The Hub of the aggregation network, called the Central Office Aggregation Unit (COAU) is collocated with the Next Generation Central Office (NG-CO) which houses the national level IP-MPLS Edge node.

The aggregation transport architecture in three tiers is indicated in the schematic in Figure 4.2. The COAU consists of the Tier-1 Carrier Ethernet (CE) switch which will handle traffic from STM-16 as well as the 10GE/100GE rings. The DWDM core is used to interconnect IP-MPLS core nodes, as well as directly interconnecting COAU Tier I switches / L2PE in case collocation is not possible. Tier-1 aggregation unit would generally utilize MPLS/RPR/100GE and would be planned for around 256 thousand users. The Tier-2 nodes are medium sized aggregation nodes called Next Generation Access Nodes (NG-AN) and would generally utilize MPLS/RPR/10GE with a plan for around 40 thousand users.

Tier- 3 nodes designated as Remote Access nodes are collocated with existing GSM towers and serve to provide backhaul for both mobile and fixed access traffic emanating within a radius of one to two kms. Enterprise traffic is also backhauled from Tier-3 nodes. The aggregation network could extend to neighbouring telecom centres through DWDM or other planned media. Tier-3 nodes would generally utilize MPLS/RPR/1GE with a plan for around 2 thousand users.

Synchronization standards for Ethernet called SyncE, defined in ITU-T G.8261, provides SDH-grade timing over lower cost 1GE and 10GE interfaces. This timing is important to ensure that time sensitive signals like voice and video do not suffer from slips beyond acceptable limits thereby preventing signal degradation. In WiMAX and LTE based mobile access that utilize OFDMA modulation techniques, phase synchronization becomes critical. In packet based networks, this can be achieved through providing an IEEE1588v2 clock.

The Next Generation Central Office at the Tier-1 location will house all the major functional systems as indicated in Figure-4.3.

Service deliverables

The integrated IP-MPLS and Carrier Ethernet Aggregation networks together would enable end-to-end MPLS services using FE, GE and 10GE interfaces from any node to any node in the country. Layer-2and Layer-3 VPN services would be available to enterprise customers. Backhaul services for mobile and broadband traffic as well as multicast services shall be available for the operator’s own use. The nodes would support classification of the traffic according to the port, VLAN, IEEE 802.1p bits or TOS/DSCP bits. Each classified Class of Service would be mapped to different EXP-bits in the MPLS header. In addition, there should be VLAN Tag support (IEEE 802.1Q) on the User Network Interface. These capabilities would allow the service provider to have reasonable degree of control over traffic engineering.

A schematic of the overall network comprising of a number of Layer-2 Carrier Ethernet-MPLS aggregation networks also referred to as ‘Converged Packet Aggregation Networks (CPAN) connected together through Layer-3 IP-MPLS network capable of delivering end-to-end MPLS services using FE, GE and 10GE interfaces is indicated in Figure 4.4.

The New Paradigm of Connectivity

The New Paradigm of Connectivity

Communication is multi-dimensional

Audio communication has been the primary means of interaction between human beings for ages. Communication can in general be categorized into more than just the physical dimension – it has an emotional dimension too. Modern Telecommunication technologies brings about an integration of video and imaging with the conventional voice, commonly known as multimedia which has been instrumental in bringing about a paradigm change in the quality of experience in communication. For instance, an application to bring about easy interaction amongst communities, an application that provides information on the location of its members, their status in terms of being available or wanting privacy, helping them with their day to day needs in identifying shops, health club, entertainment center or a school could go a long way in the entire concept of networking becoming a part of their life style. In all this, the service is not restricted to just the physical voice interaction but gets enhanced through video and imaging to bring about a rich experience. The customer feels empowered.

Birth of a new network paradigm

The previous generation network can best be described as a ‘Circuit based voice network’ that primarily catered to transport of voice signals over end-to-end nailed-down circuits or channels. There was very little flexibility in configuration of channels within a network. The ‘Time Division Multiplexing’ technology as it was called was more voice-centric, with the result that it was more expensive to transport data. The old paradigm gave way to the new one described as a ‘Packet based network’ that catered to voice, video or data in a seamless manner. The packets were governed by protocols at as many as seven layers or levels of communication – the physical layer, the link layer, the network layer, the transport layer, the session layer, the presentation layer and the applications layer. Such layer-based Packet networks afforded tremendous flexibility in specialized development based on universal standards. For instance, the Internet protocol in the network layer enabled packets to be routed in a dynamic fashion depending upon the prevailing condition of the network. Services over the new network could be offered ubiquitously. The same network could be utilized by different users on a shared basis. Packet based networks thus became far more economical as an overall business case for communication than the TDM based networks.

Role of Internet

The Internet protocol in the network layer became universally accepted as the new paradigm that was to govern global networks of the future, so much so that the resulting network was christened by the name ‘Internet’.  So much has been the popularity of Internet that the entire telecom industry had to move with the so called Internet wave. New standards were developed to adapt the use of the Internet protocol that could carry any kind of signal – voice, video or data, at mind boggling speeds to replace the conventional telephony and mobile services. The new networks that were created were christened as “Next Generation Networks” (NGN) capable of providing customers with high speed broadband. The technologies permitted hitherto unheard-of scaling factors to serve millions of customers from a single server instead of the conventional tens of thousands. Developments in mobile access technologies started surpassing those in the fixed access technologies in terms of speeds. These developments represented a unique opportunity for the Telecom Service Provider (TSP) to reduce capital expenditures by being able to offer all the three services – voice, video and data, over a single integrated IP-based (Internet Protocol based) infrastructure.  Also, core infrastructures, hitherto installed in central offices scattered over the geography, could now be consolidate on centralized basis. The operational expenditures in terms of power, space and manpower savings as a result of fewer buildings for housing equipment has reduced enormously by a minimum factor of 10. Access to the global and ubiquitous Internet combined with mobility has become an essential service offering within the NGN environment. The NGN is thus well positioned to orchestrate any access technology, and through such access, facilitate delivery of any service, at any place, through any device and at any time permitting many more new services to be offered and consequently increase new revenue opportunities for the TSP. All this has made NGN an important imperative for adoption for most service providers.

Complimentarity is critical to Communication

Through NGN, different broadband access services under land-line and mobile become complementary to each other rather than acting as substitute to each other. Such an integrated approach permits service providers to leverage on both their land-line subscribers as well as mobile subscribers by bringing on board the strength of both land-line and mobile networks through what is known as Fixed Mobile Convergence (FMC).

FMC technologies provides the customer with an opportunity to link and synergize the capabilities of the Fixed and Mobile services, while the service provider finds therein the solutions to the problems of scarcity of spectrum as well as that of customer churn. For instance, when a mobile subscriber comes within the building premises, there is loss of wireless signal strength due to absorption by the concrete walls. The in-building signal losses cause a drop in voice quality and consequent call drop.  FMC allows the calls on the mobile network to be automatically transferred to the land-line using technologies such as the Unlicensed Mobile Access (UMA) using the open free-for-all WiFi spectrum. The UMA utilizes dual band devices for the purpose – one band using the normal mobile spectrum allotted to the service provider, and the other using the free WiFi band.  Effectively, the voice is first carried over the WiFi thus solving the problem of poor in-door mobile coverage. Thereafter it is back hauled over wired broadband.

Another variant of FMC provides a ‘single number’ service to multiple devices, including the mobile, the home phone, a connected home hub, a Personal Computer or a laptop while retaining the speech quality at the same level as that which we have been used to over the conventional home phone.

Indoor coverage is also provided by technologies referred to as ‘Femto-cell’, ‘Pico-cell’ or ‘Nano-cell’ utilizing part of the licensed mobile spectrum to achieve the same objectives. 

The service provider can offer bundled wire line phone and broadband services and position FMC to churn in calls generated by customers using mobile connections of its competitors, thereby offering better coverage and “always connected” services to its subscribers, independent of device.

IMS to govern the future of Communications

At this time, Mobile network operators the world over are planning to leverage emerging IP Multimedia Subsystem (IMS) service platforms to deliver not only true “one phone, one number” telephony over both fixed and mobile infrastructure but also extend the plain phone service to multimedia service through what is known as ‘Voice-over-IP’. Multimedia service thus combines the voice, video and data into a single contextual session.

The one phone, one number concept enables a mobile handset to use 2G/3G mobile infrastructure and the associated 2G/3G spectrum when it is operated outdoors and ‘VoIP over WiFi’ or ‘Femto-cell’ when it is operated indoors at work or at home. Global standards for IMS and associated FMC have been developed by the 3GPP Standards body and ratified by 3GPP2, ITU, ETSI, TISPAN and others. It has become clear that the immediate benefactors of IMS shall be those operators who already have both fixed and mobile deployments in good measure.

A two pronged approach was followed by service providers whereby the first approach would bring about convergence at the device level.  The existing mobile network was optimized with IP architectures and adapted to directly support IP devices.  There was, of course, an obvious dependency on devices such as dual-mode handsets, integrated residential communication hubs, etc. that became increasingly prevalent in the market.  The second approach was a deeper and more meaningful transformation of the core network into IMS that would bring about true convergence based on transformation towards the all-IP core network.  The essential component in this approach was the preservation of existing mobile services. The service provider would then use an IMS platform to transparently combine regular mobile service on their 2G or 3G mobile networks with VoIP services over WiFi and/or fixed broadband access. Since the mobile portion of FMC used the existing mobile number and existing mobile switching systems, mobile operators with significant fixed deployment would obviously derive a distinct advantage.

Bringing Societies together

The business of connecting a nation with over a billion population is about connecting a diversity of entities having interest with each other, popularly known as social networking. It is not about merely connecting individuals on a one-to-one basis. We are connecting communities of citizens with a lot of expectation. We are connecting people with common interests – societies, organizations, markets, banks, economies, schools, colleges, universities, hospitals or simply friends, families and relatives. There is a pattern in each such connecting construct upon which an application can be weaved. It is these applications that dive deep into the emotions and behavioural pattern of individuals that create a need which was hitherto dormant. For example, the Facebook brought about very old, almost forgotten friends together. The future of communications would be intimately tied with scores of such applications working seamlessly not only across networks but also between different devices.

The convenience of the triple screen has been spoken about in technological circles quite at length – screens formed on television, the mobile handset and the personal computer. Tremendous convenience of the touch Pad, also called the I-Pad or simply the ‘Tablet’ would address the choice of ‘Quad’ screen. Seamless communication would mean that a set of common friends share their presence over these screens without any restrictions whatsoever. They could chat with each other on instant messaging, share pictures or documents around which a discussion could be centered. The chat mode could be transferred to voice or even video as need would suggest.

Cloud computing is seen as a major technology that could actually off-load much of the processing power from the PC. The price points of simple touch screen tablets could come down drastically and customers could be offered applications on “pay-as-you-use” model.

Vision for a Connected Society

The ultimate vision for a connected society would have to thus evolve out of the present day ‘cut-and-dry’ connectivity plane into the societal plane, delving very much into applications that meet emotional expectations, while enrichening and enhancing their interactive experiences. Convergence of a wide range of fragmented technologies known by the acronyms such as 2G, 3G, GPON and DSL has shown how these objectives could be technically met. The challenge really lies in bringing about such convergence through an economical model that renders several of the more common and relevant services affordable to the masses. 

From the customer’s perspective, what is needed is a broadband pipe working on Internet protocol. If however, public-Internet service is all that is provided over the broadband pipe, such a situation can impose severe limitations on the quality of service. This is because the traffic in the public-Internet space, what is often referred to as the cyber media, is handled by routers belonging to different entities the world over and as such becomes uncontrollable and is understandably termed as ‘unmanaged network’. Traffic bottlenecks in the unmanaged network often result in packet drops or packet delays, both of which cause severe impairment to the quality of service. The traffic in the public Internet space is also susceptible to cyber crimes. 

The Telecom Operator can however offer broadband through Gateways that are capable of providing the customer the choice of accessing the global Internet on one hand or any of the services provided over the managed IP network of the operator on the other, as shown in Figure 1 below. These gateways are called Broadband Network Gateways (BNG) in the case of Fixed Access networks and the combination of Serving GPRS Support Node (SGSN) and Gateway GPRS Support Node (GGSN) in the case of Mobile networks. The broadband access channel is partitioned into two Private Virtual Circuits (PVCs) thus creating separate paths for the global Internet and for the Managed services.

The voice services provided over the managed IP network, also referred to as VoIP services, can match the PSTN voice services in terms of quality and other parameters and will therefore be superior to the ‘Internet-telephony’ services provided over the public Internet. Likewise, the managed IP network can be used to offer video services in comparison to similar services delivered over ISDN of PSTN. The Services provided over the Managed IP network can be operated under the Basic Service and the Cellular Mobile Telephone Service (CMTS) licenses whereas the Internet service can be operated under the Internet Service Provider license. Alternatively, the same set of services can also be provided under the Unified Access Service license (UASL). The security conditions relevant to the respective licenses will become applicable.

The operator as a matter of strategy can configure all its broadband customers to receive free incoming Voice and Video calls, thereby bringing its new ‘Voice & Video over IP’ (VVoIP) subscribers at par with any other subscriber in the network in terms of diversity of access. Such next generation techniques significantly enhance the propensity for growth of VVoIP services. The growth of telecom industry would no longer be measured by the conventional “tele-density” but by a new parametric called “tele-service density” that will ad-measure the aggregate number of application service users taking into account all the applications per 100 population.

Convergence of old and new networks

With so many new technologies, it is expected that the networks using these technologies inter-operate seamlessly not only with each other, but also with the older technologies which it bids to replace, thus protecting older investments. Thus the new NGN switches inter-operate with the older TDM switches through what are known as ‘Media Gateways’ (MGW). Similarly in the Transmission space, the new Carrier Ethernet networks inter-operate with the older SDH equipment through ‘Ethernet over SDH’ interfaces or through the use of ‘SDH emulation over Carrier Ethernet’. We would need to adopt a seamless migration methodology to migrate from the old CMTS networks to the new IMS networks. The emphasis will be from customers using disparate networks to customers using convergent networks which have platforms that enable the operator to view the customer as a single entity with a single face though using a variety of services.

All you wanted to know about "Spectrum"

All you wanted to know about "Spectrum"

What is Spectrum?

Spectrum is a term for electromagnetic radiation or simply air waves used for communication between two entities. The intelligence is embedded in the air waves through a process called modulation at the transmitting end and the same intelligence is extracted in its original form through a process called demodulation. A slice of spectrum contains a band of frequencies. The wider the band, the more information-carrying capacity it has and we say it has more “bandwidth”. Bandwidth is generally measured in thousands, millions, or billions of hertz.

·           Kilo hertz (1,000 Hertz) is written as kHz

·           Mega hertz (1 million Hertz) is written as MHz

·           Giga hertz (1 billion Hertz) is written as GHz

The process of compression and modulation can pack more and more information bits in a given bandwidth. Text transmission requires the least information bits per second in the range of about a kilobit per second or simply 1 kbps. Digital voice requires about 10 kbps, digital music about 100 kbps, standard definition digital TV about 2 Mbps, high definition TV about 10 Mbps, and so on.

The electromagnetic spectrum has long wavelengths (low frequency) at one end and short wavelengths (high frequency) at the other end. The wavelength affects a signal’s propagation characteristics, including its ability to pass through objects. As a signal passes through objects, it is gradually weakened. Although every object the signal encounters weakens it, some weaken it more than others. The air we breathe, for example, weakens it less than the drops of water in a rainstorm, which in turn weakens it less than a brick wall. This weakening is called absorption, and absorption tends to vary by wavelength. Longer wavelengths are less likely to be absorbed by dense objects such as clouds, trees, cars and homes. This is a key reason that low frequency spectrum, such as the bands traditionally assigned to broadcasters are most valuable.

Spectrum has been put to several uses, most notably during the early days of TV by broadcasting stations which are equipped with a single powerful transmitter so that it can reach out to a vast number of radio receivers owned by citizens. The next popular usage has been to communicate between two entities, both equipped with a set of transmitter and receiver each. The third major usage has been for extending wireless services to large number of subscribers limited to within their respective cell boundaries.

The cellular control technologies enabled the usage to be extended to mobile subscribers moving across cells using handheld devices without any interruption in service. The mobile system and devices had to meet exacting requirements such as limiting transmit radiation to overcome health hazard standards, increasing receiver sensitivity and a host of popular subscriber features. Even so, these could be met at mind bogglingly low costs because of the huge subscription numbers and the overwhelming subscription for the mobile service. Today’s mobile service popularly called 3G allows very high download speeds for viewing video clips and the like, in addition to the more conventional voice and text messaging services.

Who owns Spectrum?

Certain concepts need to be developed from the fundamental level. We have been used to accepting some concepts without ever questioning fundamentals. Spectrum is an example. Air waves like water or air belongs to society as a whole. Every citizen has to be a benefactor. There ought to be equitable use. Yet we find that not enough awareness is there amongst citizens about this. How many of us, for example, know how the full range of electronic spectrum is being used today? We only tend to be aware of what is being focussed by the media. Take for instance, the recent 3G spectrum allocation. 3G spectrum is just a small fraction of the total spectrum available, yet it was initially valuated at only about $7 billion and actually yielded $11 billion in the public auction.

It must be realized that spectrum does not have any ownership. Even the government does not own it, just as much as it does not own the air or the water available in nature. Government is just a trustee who is entrusted with the task of ensuring fair and equitable usage of these resources by public through the instrument of public policy. Thus it would be inappropriate to enunciate a policy that only considers maximizing government revenues in a public auction at the exclusion of other collateral benefits to society such as increase in GDP and consequentially increase in employment. In the present context of 3G spectrum, questions need to be asked whether the 3G subscriber growth and consequent revenue growth are commensurate with the auction prices paid by the operators. Would the country not have been better off at say only half the auction prices but with a much higher growth rate?

The public therefore has a right to know how the entire range of spectrum is being utilized in the country. It needs to know which entity is given the rights and for how long. No one should be assigned any portion of the public property permanently. We find in India as well as in many countries that specific information on spectrum is shrouded in mystery, very often in the misguided name of internal security. This was the old parochial mindset, which should no longer be valid in today’s open society. We need to know why there is such a huge discrepancy between what the proverbial insiders know and what the general public knows. If we are to represent the interests of the common citizen in a vibrant democracy, we need to change this mindset and open the spectrum policy to intense public debate, thereby ensuring greater transparency with the ultimate objective of ensuring efficient spectrum usage and management. To be able to do this, we need to be clear as to what constitutes value when we talk of spectrum.

Valuation of spectrum

Willam Safire of New York Times stated that spectrum is the most valuable natural resource of the information age. The New America Foundation in its Citizen’s Guide to the Airwaves seeks to draw the American public’s attention to the tremendous value of spectrum which is really speaking as per the Communications Act of 1934 belong to the public and states that “it is the purpose of this Act, among other things, to maintain the control of the United States over all the channels of interstate and foreign radio transmissions; and to provide for the use of such channels, but not the ownership thereof, by persons for limited periods of time, under licenses granted by Federal authority, and no such license shall be construed to create any right, beyond the terms, conditions, and periods of the license.”

According to a report of the US General Accounting Office (Sept 2002), the basic problem is that demand for spectrum is outstripping the supply. Thomas Hazlett, Former Chief Economist, FCC confided that the spectrum allocation system is inefficient, unresponsive to consumer demand, and a huge barrier to entry for new technologies anxious to compete in the marketplace.

Many factors have caused the valuation of spectrum to increase dramatically over the last few years. Different frequencies have different propagation characteristics that have a huge impact on their market value. Higher frequencies are less valuable than lower ones because popular consumer services (broadcasting and cell phones) need to penetrate buildings, and this gets harder as you move up the spectrum. To estimate the valuation of spectrum, it is convenient to classify frequencies into four zones – the permeable zone where frequencies up to 2 GHz have maximum ability to penetrate objects easily, the semi-permeable zone where frequencies from 2 GHz to 5 GHz have difficulty in traversing dense objects, the long line-of-sight  zone where frequencies from 5 GHz to 50 GHz cannot traverse dense objects and lastly the short line-of-sight zone where frequencies from 50 GHz to about 300 GHz can traverse only very short distances. It is not difficult to understand the statement that the 1% of frequencies below 3 GHz are worth more than the 99% of frequencies from 3 GHz to 300 GHz.

Why is it necessary to valuate spectrum? If spectrum was in plenty and therefore had little value, fair usage of spectrum would not become an issue and everyone’s stake would be fulfilled. The fact that demand for spectrum far outstrips its supply necessitates a fair-use spectrum policy that logically needs to be related to its valuation. Without a fair valuation of the scarce resource, which ultimately belongs to the public, there could not be a basis for a fair-use policy.

Also, restrictions on what a licensee can do affect valuations in competing ways. For example, a television broadcaster is not free to abandon the television broadcasting business and become a mobile telephone operator (a relatively more valuable use) with the frequencies assigned in its license. At the same time, however, restrictions on other licensees mean a television broadcaster does not have to fear an influx of new entrants into its business, which would tend to reduce profits and hence the value of its license.

The New America Foundation’s Citizen’s Guide to the Airwaves postulates four valuation concepts, viz.

“Current use value” where the licensee receives no new spectrum flexibility and the bundle of rights in a license to use spectrum does not change,

“Marginal flexibility value” where the licensee, but no one else, is granted complete flexibility in the use of the spectrum, i.e. a single licensee, but none of its potential competitors, wins the right to use assigned spectrum any way it chooses,

“Universal flexibility value” where the licensee is granted complete flexibility in the use of the spectrum, but potential competitors do as well, and lastly,

“Partial flexibility value” where a subset of licensees is granted complete spectrum flexibility.

How these concepts become key to making policy decisions can be gauged by considering the real estate analogy of property zoning at a prime location that restricts the real estate to be zoned only for residential plots. Assume that there are a thousand plots each of one acre. In course of time all the plot owners would want to upgrade from residential to commercial zoning, so that they could all engage in commercial activity. With current use value, no plot owner can build a commercial complex. With marginal flexibility value, only one plot owner gets rights to build a commercial complex. With universal flexibility value, all plot owners get rights to build commercial complexes. Obviously, the flexibility to build a commercial complex is more valuable if everyone else doesn’t also have that right. Partial flexibility value is the intermediate case, where, say, 100 of the 1,000 plot owners get flexibility to build a commercial complex each.

Valuation would have to be done with the help of a measurement unit. As part of the postulate, the unit is defined by two parameters: bandwidth (MHz) and population coverage (pop). Larger bandwidth increases value because it increases the information carrying capacity of a license. Population coverage refers to the number of people—including potential customers—living in the geographic area designated by a spectrum license. The right to use spectrum in highly populated areas is usually much more valuable than the right to use it in sparsely populated regions. If a 1 MHz band of spectrum sells for $1/person, then its value is $280 million if the band covers all 280 million people in the United States. The unit of measurement would therefore be dimensioned as “$/MHz/pop”.

Spectrum has many commercial uses, and the current use value of the spectrum in these uses varies considerably. The citizen’s guide calculates the value of the spectrum in a handful of different commercial uses, focusing on the economically most important ones. The sum of these values indicated in Table 1 for current use value works out to $301 billion.

Table 1. Current Use Values

Application	Frequenciesa	Total MHzb	$ /MHz/pop	Total Value
Mobile Communications
Cellular	824-891.5 MHz	50	$4.18	$59.50B
Broadband PCS	1850-1975 MHz	120	$4.18	$142.80B
Other	806-940 MHz	15	$4.18	$17.85B
Broadcasting
VHF & UHF TV	54-806 MHz	402	$0.233	$26.19B
Radio	0-108 MHz	21	$8.19	$48.16B
Satellite TV	12.2-17.5 GHz	900	$0.021	$5.34B
Satellite Radio	2320-2345 MHz	25	$0.040	$0.28B
Fixed Communications
LMDS	27.5-31.3 GHz	1300	$0.0024	$0.87B
39 GHz	38.6-40 GHz	1400	$0.0015	$0.59B
News Gathering	1990-2025 MHz	35	$0.0204	$0.20B
		Grand Total		$301.78B

Note:

a.      This indicates the range of frequencies in which this service is located. The entire spectrum   range is not necessarily used for the indicated purpose.

b.     This column shows the total amount of spectrum used for the indicated purpose.

The Marginal Flexibility Value Curve represents the value of radio spectrum in its highest valued use today. The general shape of the Marginal Flexibility Value Curve, indicated in Figure 1, is driven by a combination of physical and economic factors. The most notable feature is the steep drop in value that occurs in the 3 GHz to 5 GHz range. For frequencies below that range, radio spectrum is most suitable for mobile uses, such as wireless phones and radios in cars, and non-line-of-sight applications like terrestrial television broadcasting and wireless home computer networking.

The existence of a discrepancy between the current use value and the marginal flexibility value indicates that there is an efficiency loss coming from not allowing the spectrum to be used for services most highly valued by consumers. If however, the spectrum were to be utilized efficiently, what policy would the government apply to incumbents in order to ensure fair usage vis-a-vis competitors? A possible option would be that the government could charge market rates through a public auction, etc. for use of this spectrum which is a public asset, with the receipts going into the treasury rather than the pockets of spectrum incumbents.

When the flexibility of spectrum usage is thrown open to one and all, there would occur a sudden surge in supply as a result of which the average flexibility value under universal application would fall.

If it is assumed that, on average, current use values vary smoothly from the marginal firm to firms that are able to earn twice what the marginal firm does on the spectrum, then the producer surplus is half of the marginal value of $301.78 billion, or $150.89 billion. This brings the total value of spectrum to licensees to $452.67 billion.

Further, the Delphi study suggested that over the next decade alone, a gain of $318 billion can be realized by more efficient spectrum use. For instance, today’s mobile telephone networks reuse the same frequencies hundreds of times in a given metropolitan area. With digital technology, the same 6 MHz that could only carry just one standard definition analog TV channel in 1960 can today carry ten such channels through digital compression and multiplexing technology. The sum of these two values viz. the total value of spectrum to licensees and the additional value realization by more efficient spectrum usage is just over $771 billion for potential total value to license holders of licenses for completely flexible licenses.

Now we may compare this with the $11 billion valued for the 50 MHz 3G band in India. In order to comprehend the true magnitude of the radio spectrum’s worth, the citizen’s guide compares the total spectrum value to other financial resources. At an estimated $771 billion, spectrum is worth more than the Empire State Building ($1 billion), McDonalds ($31.2 billion), all the gold in Fort Knox ($45.5 billion), Bill Gates ($52.8 billion), the annual amount the federal government spends on Temporary Assistance to Needy Families ($24 billion), the annual amount it spends on Medicaid ($147 billion), and the annual amount it spends on National Defence ($357 billion) all put together. Stakes as large as this is good reason to judiciously carve out a fair-use licensing policy as a national endeavour.

With a coverage population of India being about four times that of the U.S. and rural coverage issues much the same in both cases,  the stakes for India seem to be all the more greater. A national level debate on the issue would place India on a logical footing as far as securing the desired macro economic growth rates and GDP are concerned.

Licensed Spectrum

Licensed spectrum bands are those bands which have been leased out for a fee by the government to users who are given exclusive rights for a specific use, for a specific time period either to provide a consumer service such as broadcast TV, mobile telephony, etc. or as a support utility for retail and industrial spectrum to be used by agencies such as the police, railways, airports, companies, etc. Licensed bands constitute a vast majority of total spectrum, about 98% and is considered to be for primary use and therefore given priority on the band.

Unlicensed Spectrum

Unlicensed spectrum bands are free bands for use by citizens on shared basis without any guarantees against interference. These bands are generally restricted to exceptionally low powers, which in turn restrict the users from sending signals very far. However, this restriction allows the same spectrum to be reused by users within their limited premises, thus extending the usage to millions of users all over the country. Typical usage of unlicensed spectrum include low power walky-talkies and audio-video remote controls for TV sets, DVD players, VCRs, remote controlled toy cars, garage door openers, toll passes, baby monitors, etc. Unlicensed spectrum bands constitute an insignificantly small fraction of total spectrum, viz. 2% and are considered secondary use, and can share the band as long as they do not interfere with the primary use.

 Spectrum for Rural requirements

The spectrum is not equal in different frequency bands. Different bands have different characteristics and, therefore, are better suited to particular types of wireless services. In general, lower the band, the greater the propagation which translates into broader coverage from a single transmitter. The same range can be achieved in higher frequency bands by building more transmitters, but only at a substantial cost. Unlike most other spectrum users, Rural and Public Safety users do not have the luxury of limiting their operations to areas with significant population density. They must be able to communicate throughout their areas of responsibility and jurisdiction. Their terrestrial coverage must have as broad a geographic reach as is technically possible and financially sustainable. Should public safety be required to meet its coverage requirements in higher bands, significantly more infrastructure would be needed to cover the same geography which would substantially increase initial equipment costs, the complexity of building a network, and ongoing operating expenses.

Rural and Public Safety are critical national requirements affecting huge percentage of population close to the poverty belt. Spectrum in the Sub-band, viz. GHz700 MHz or 450 MHz bands, would be ideal candidates and any of these could be regarded as the prime contiguous band that lends the necessary support to the economic criteria where India would need to spend less on broadband operations and concentrate more on actual deliverables to the citizen. Prioritization over the actual needs of the citizen would therefore require to be exercised in deciding the spectrum usage, in addition to considering the actions of other countries such as the US, that have similar problems as that of India as far as rural coverage and disaster management are concerned. The extra coverage in say 700 MHz translates into more cost-effective networks for the rural Broadband communications. We estimate one base station that operates in 700MHz band can cover the same area as four base stations in 1900 MHz or 10 base stations in 2.4 GHz bands as illustrated in Figure 2. Installation and maintenance costs are reduced by having fewer base stations. 

                                           Spectrum is a scarce resource

As the subscription for mobile service increased, cell sizes shrank from a radius of about 2 km to as low as 100 metres in certain cases. This peaking happened at most in two or three localities in dense urban areas. The issue of allotment of additional spectrum by the government then arose. A simpler and more economic way to work around the problem was to use in-building solutions in these limited dense urban localities instead of securing allotment for additional spectrum which would span the entire licensing area instead of just the two or three localities in dense urban areas and thereby increase the costs enormously.

It must be remembered that the spectrum costs which were directly related to opportunity costs had by this time risen to astronomical figures. In fact, the license for spectrum became a dominant factor in market valuation of an operator company.  The government had more-or-less veered to the conclusion that any allotment – fresh or additional – should be made through the route of public auction. This was in line with the global trends.

Conservation of Spectrum

There are several ways in which scarce spectrum could be conserved and efficiently utilized. The most fundamental way of spectrum conservation is through the use of in-building solutions through creation of femto cells, typical deployment of which is shown in Figure 3 with one main BTS unit and three remote units covering three buildings. The main unit and the RF remote units are generally connected on optical fibre. The Combining box is used to support multiple bands with remote units of different operators along with distributed antenna systems (DAS). The benefit of microcells is their capability to increase capacity without generating too much interference due to their limited coverage. Microcells are characterized by lower output power and lower antenna placement compared to macrocells.

                 

A somewhat similar end is achieved through the ‘Fixed Mobile Convergence’ or simply ‘FMC’. FMC is about transforming the mobile operator network to enable service delivery to the home and office via the broadband IP network over the fixed line using WiFi Access in the unlicensed band. Since 60% of calls are known to be made from indoors, FMC virtually offloads voice traffic from the spectrum to the land line, thereby directly reducing congestion in the scarce spectrum.

Another important technique that improves voice capacity is Enhanced Power Control (EPC). EPC is already standardized in Release 5 standards of GSM. While GSM today can change power levels every 480 msec (in each associated control channel block), with EPC GSM can adjust the power level every 120 msec (every SACCH burst). For faster moving mobiles, EPC can improve network capacity by 20%.

Frequency Hopping consists in changing the frequency of the channel in every transmitted burst providing frequency diversity and interference averaging. Frequency hopping is not usually applied to the channels employing the control channel, and this portion of the spectrum is referred to as the non-hopping layer. In the non-hopping layer, which contains the broadcast control channel (BCCH), operators deploy traditional re-use patterns such as 4/12. In the hopping layer, operator can deploy tighter re-use patterns such as 3/9, 1/3 and 1/1. In the 1/1 re-use pattern, the entire pool of hopping frequencies is available in every single sector. Fractional loading may be in the range of 20% to 30% or even in the range of 40% to 60%.

Compared to the Enhanced Full Rate (EFR) codec, Adaptive Multi-Rate (AMR) Codec can operate under much worse radio conditions such as with a heavily loaded network.  The AMR gives greater spectral efficiency and hence higher capacity with Better voice quality throughout the cell especially at cell edges and deep inside building and increased overall coverage. The AMR feature is network as well as mobile phones dependent. However, the benefit of AMR does not depend on all mobile phones implementing AMR. As the percentage of mobile phones with AMR increases in the network, the efficiency of the network increases.

GSM is an ever evolving technology. A very large telecom community is putting tremendous efforts in spectral efficiency enhancement techniques. Some of the evolving methods to increase spectrum efficiency are Capacity boost by Antenna Arrays, Network Synchronization, Single Antenna Interference Cancellation (SAIC) technique and the use of Smart Radio.

A substantial capacity gain may be achieved by using antenna arrays in a microcellular system. Here, the control channel covers a traditionally shaped sector, whereas the communication on the traffic channels is confined to a narrow beam between the base station and mobile station. These narrow beams improve the C/I in both the uplink and downlink. The gain obtained by the antenna arrays can efficiently reduce interference and thereby increase capacity.

Today’s GSM networks are asynchronous, meaning that any given base station does not attempt to align its transmitted signals with other base stations. Typically, the best performance is achieved when the dominant interfering signal (burst) does not change characteristics throughout the desired signal’s burst. One way to ensure this is to synchronize base stations and align all bursts to a common timing source, e.g. a GPS clock. Although frequency hopping works effectively in asynchronous networks, synchronized networks enable a new powerful means to control the interference. Interference control is achieved by coordinating the frequencies that a given sector will hop over amongst all relative interfering sectors and staggering the order in which they hop over the frequencies. Without network synchronization, such interference control is generally only possible between sectors of the same base station, but with synchronized networks the interference avoidance is possible between any sectors irrespective of the base station. Synchronization further aids in the identification of the neighbouring cells, which is needed for handover and location measurements.

Single Antenna Interference Cancellation (SAIC) technique improves downlink performance for GSM networks. SAIC is basically a technique to boost the capacity of GSM network without needing any change in the network. It is in the interest of network operator to use the allocated spectrum as efficiently as possible and to the highest possible capacity because a substantial investment is done to secure the license for it. It would be desirable to have the frequency reuse of one, which means that each cell can operate in the same frequency. This in turn creates interference to the users operating in the nearby places. Increase in interference cause the voice quality to drop and may cause call drop. It is a well known fact that it is possible to cancel the interference at the mobile handset side by changing the baseband software without changing anything in the network side. SAIC enables mobiles to work in high interference level. SAIC enabled mobiles need even less transmit power from network which in turn reduces the interference for non SAIC mobiles. Theoretical studies show that with 100% SAIC mobile penetration a capacity gain of 60 to 80% is achievable. SAIC capable handset penetration is expected to increase over the next few years.

Smart Radios

None of the aforesaid technologies however appear to be as revolutionary as smart radio, which not only promises a huge increase in spectrum efficiency, but also enforces a rational spectrum policy management. Smart radio, as the name implies, adds context sensitive intelligence to signal processing. Think of the difference between a human ear and a microphone. A human ear has a fine-tuned ability to discriminate between noise and signal. In a room full of conversations, it can focus on a particular conversation of interest. A microphone, in contrast, treats all conversations equally and generates unwanted background noise if all other people in the area covered by the microphone don’t keep quiet. This is extremely inefficient because a room, instead of supporting many conversations, can now only support one. Smart radio allows many different “conversations” to share the same spectrum. One of the most important features of smart radio is that it can not only frequency hop across  large bands of spectrum, but also, like a universal translator, understand and speak in the wireless language of each of the bands it uses. A single smart radio has the flexibility to provide all the wireless services of hundreds of dumb radios, including FM radio, broadcast television, cellular telephone, cordless phone, and remote control.

Smart radio can create an “open network” and allow the dynamic sharing of frequencies. Consumers and vendors can easily switch frequencies, thus diminishing the monopoly power of license holders. They can also spread their equipment costs across many services and frequency bands, thus reducing the total cost of spectrum. It’s like having one personal computer that can perform word processing, database, spreadsheet, graphic design, video editing, telephone, television monitor, stereo, Internet, and other functions rather than having a separate device for each of those functions.

Spectrum Policy

Though it appears that the spectrum has reached its frontier as far as exploitation of its full range is concerned, with new technologies such as “smart radio” there is great opportunity to use our existing frequencies far more efficiently than they have been in the past. This further creates a need for new spectrum policies – including more unlicensed spectrum, more frequency sharing, and shorter license terms – that can minimize spectrum scarcity and deliver low-cost, high-speed mobile Internet access.

More than anything else, Smart radio fundamentally changes the economics of licensing. Today, there are substantial efficiencies gained from granting long-term licenses of as much as a decade or more. This is because license holders need to recoup substantial investments in specialized (i.e., dumb) spectrum equipment. In the future, if both transmitters and receivers can easily be reprogrammed to use a variety of frequencies, the efficient term of a license may drop to microseconds. Smart radio, with its superior ability to distinguish signal from noise (because signals speaking different “languages” are not mistaken for noise), also allows for much more efficient management of interference. A “listen before talk” protocol, for example, assumes that a radio can first distinguish between signal (conversation) and noise (unused spectrum). This capacity to distinguish between signal and noise allows different users, such as licensed and unlicensed users, to coexist in ways not previously possible.