The rural challenge is how to maximise revenues in a scenario characterised by low average revenue per user (ARPU) and high total cost of ownership.Operators usually face three key issues when setting up networks in rural areas: civil works (including towers/shelters) which dominate the site cost; unreliable or no supply of grid power and high operating expenditure of diesel gensets; and lack of or costly transmission networks.
Nokia Siemens Netwroks (NSN) follows a multi-pronged strategy for different types of rural areas. Operators should, for instance, maximise coverage using high mast and coverage enhancement features (Smart Radio Concept, DPTRX, e-cells, etc.) in sparsely populated areas. In other rural areas, wherever the business case allows, coverage should be enhanced while reducing site costs; outdoor sites should be introduced: mast tops, shelters and aircons should be eliminated; and power needs reduced. In areas where the traditional business case is negative, operators should focus their coverage carefully and specifically with ultra low site costs.
NSN offers many coverage solutions for rural GSM networks:
Mast-top smart sites, for instance, have the advantages of no feeder loss of the base transceiver station (BTS) enhanced coverage; 30 per cent reduced power consumption; smaller wind load; the potential to add tower load with BTS, antennas or microwave radiometers; improved protection against equipment vandalism; no requirement for shelters or air conditioners, etc. The flexi base station leads to about 70 per cent lower energy consumption and a reduced carbon footprint.
ZTE has also come up with GSM solutions for rural areas. It has introduced a low-cost base station controller (BSC) with the following specifications: 15,000 Erl, 4200K BHCA, 3072 TRX, small footprint 0.48 square metre and 3200 TRX per square metre. The solution provides flexible access (with E1/STM-1, IP, satellite) and high reliability as it has commercial applications all over the world with mean time between failures (MTBF) of over 100,000 hours. It has only 16 hardware boards and shares its IP hardware platform with cellular networks.
ZTE has also unveiled a macro indoor BTS for dense urban areas and areas of high traffic. This is suitable for all kinds of scenarios: green and low power consumption. The Chinese telecom equipment manufacturer has also come up with a G/U software defined radio (SDR). The SDR Node B has four key factors: MCPabased wideband radio unit, sufficient output power with HPA, MicroTCA structure band unit and high integrity and process capability. The SDR application’s key advantages are that it utilises 100 per cent of the existing hardware, can flexibly configure the network, allows investment protection and is evolvable.
ZTE also offers distributed BTSs that can be placed on the wall, in a 2G BTS rack, transmission rack, etc. The outdoor radio remote unit is protected against all fluctuations of weather, tropical rain, freezing, storms and desert conditions.
ZTE’s Micro BTS M8206 saves 1- 1.5dB feeder loss, has no fans (resulting in opex savings), non-offensive installation, installation fee, integrated transmission IDU, the lightest 6 TRX compact BTS in the industry (20 kg per module), nature dissipation system (noise-free) and strong temperature adaptability.
The solution can fully support IP Abis Transmission, 48 V DC input with solar power systems and 110 V/220 V AC input, generator and wind power source.Satellite and IP OFDM are the most cost-effective solutions.
ZTE has implemented the Micro BTS for China Mobile (Chong Qing) in the rural regions. Until now, ZTE succeeded in continuous expansions, including swapping existing sites. The company has successfully deployed 13155 TRX/4517 Site and BS8900 in Chong Qing areas to cover villages. These are outdoor BTSs with no equipment room cost, super-low energy consumption, build-in rectifiers for AC, 6U spare space for equipment and support for IP transmission.
The Chinese company has also tied up with Tata Teleservices Limited to provide its SDR solution. The solution, which can be applied on a large scale, benefits Tata as it results in the utilisation of existing infrastructure saving capex and opex, saving expansion investment, etc. 2G and 3G are supported by the SDR base station.
Passive and active network infrastructure sharing are other important cost saving strategies for rolling out services in the rural areas. The three key models of network sharing are: multi-core network sharing (separate cellular networks and a common radioactive network); common cellular network and common radio active network; and common network sharing (geographically split, coverage difference and roaming principles).
However, there are concerns. BSC sharing is difficult due to issues with resource distribution and management, while BTS sharing involves antenna and feeder sharing.
However, wireless broadband is the way to go in villages. There isn’t enough wireline infrastructure. Legacy networks have long loop lengths. The cable infrastructure is unorganised with poor network. This results in high buried access costs, limited greenfield deployment, limited content offering ?? restricted utility for access, etc.
Wireless broadband, in comparison, has a far more superior rollout mechanism with the additional advantage that existing wireless players have their necessary infrastructure in place. Spectrum auction for broadband wireless access (BWA) is likely in the near term. Players are likely to provide large coverage and faster expansion as soon as they receive BWA spectrum.
Motorola has come up with a reach strong box local sourcing solution. The solution reduces the cell site cost. It houses standard horizon II 4/4 macro (this can be upgraded for 3G). Direct air cooling is provided to reduce the power requirement. It works via a distributed format, which makes operations simpler for remote sites.
The reach eco-site runs for 12 months and is a wind-solar combination cell site. It has Horizon II DC mini 2/2 configuration via voltage regulators to battery, and enables site monitoring and the management of power systems.
Motorola has different solutions. For backhaul it has high throughput IP connectivity. For mesh it has secure connections over Wi-Fi and public safety bands.Canopy is its proven wireless broadband access solution and Wi-Max is its high performance standards-based broadband wireless access technology. Wi-Max is definitely an effective alternative for last mile access in rural areas.
Sandeep Bhargava, Head, Corporate Affairs, APAC, NSN India; Debashish Bhattacharya, Additional Director, Technical, ZTE India; and Deepak Mahajan, Head, Marketing, Home and Networks Mobility Business, Motorola India
