Wireless in Local Loop [WLL] Emerging Technology
Reasons of Using WLL
Any service provider or organization should strive to provide high quality service in the most economic method available to end-user, the customer.
Telecommunication is no exception and therefore, it is necessary to keep abreast of Technology advancements and innovations to provide the best quality of service at lowest cost possible to the subscriber.
In the last 20-30 years, we have seen switching equipment move from manual boards, Magneto exchanges, strowger etc, to the sophisticated Electronic SPC Switches now in use, viz E-10B, OCB-283 & EWSD etc.
Transmission technology has also advanced, thus far to optical Fibre Cable, Microwave Radio, Satellites Communications etc, and is continuously developing.
The local external Network or the local loop also needs adoption of new techno logies, as it is this part of Telecom Network which accounts for approximately 60% of the total cost of whole, Telecom network. By embracing newer technology in the External Plant, we can maintain a high QOS (Quality of service) and reduce the cost to the subscriber. This means we can offer “Voice and Data Communication” to a much greater percentage of the population, previously denied access (for reasons of insufficient disposable Income) to telephone, Fax and Internet Services etc.
This may be illustrated by:
The average household income in India permits affordable expenditure on Telecommunication services, apportioned across the population, as follows:
Average Affordable expenditure on Telecomm Services
By percentage of population
Rs. 120 per month
Rs. 160 per month
Rs. 200 per month
Rs. 400 per month
Rs.1000 per month
And also, the total investment required to install a telephone with conventional Wire Line technology, is approximately Rs.30,000/- to Rs.35,000/-. Looking at the above data/figures, it is evident that cost reduction in the external plant part of Telecom Network is very much essential.
The Radio in local loop, i.e. wireless in Local Loop, if not better service, than Wire Line or Landline, but is an equivalent local loop service compared to wire line services and at lower cost.
The economics of wire line versus wireless are
The cost of installing or Maintaining Wire line systems broadly depends on the cost of Labour (Laying Ducts, digging Manholes) whereas cost of wire less depends on cost of subscriber unit, which tends to fall over time, with increasing economies of scale.
Cost of wire line is more due to use of copper a costly metal in U/G cables whereas WLL is independent of this factor.
Cost of wire line system critically depends on the distance between houses and the penetration levels achieved. These factors are not applicable in WLL.
If a subscriber moves to a different operator in case of wire line system, the investment is lost, whereas in the case of WLL, the subscriber unit in such case is simply removed and installed elsewhere.
The cost of wire line system is incurred, even prior to Marketing to the users, whereas much of the cost of WLL is not incurred until the users subscribe the Network.
The widely used WLL systems are:
corDECT WLL: This is digitally enhanced cordless Telecommunication
The standard is defined by ETSI (European Telecommunication Standard Institute).
CDMA – WLL: An American System as per IS-95.
Requirements for a Wireless Local Loop System
The WLL must provide all services supported by the wired local loop with the same or better quality.
A Wireless Local Loop (WLL) system is meant as a replacement for the traditional copper twisted-pair local loop. The WLL system is expected to provide a superior alternative to buried cable. The main purpose of the WLL system is to substitute a wired local loop for providing fixed telephone access. The WLL must, in general, provide all services supported today by the wired local loop, and also those, that are likely to emerge in the near future. Further, it must provide these with the same, or better, quality.
The requirements of a WLL system can be broadly divided into five categories: services, capacity, PSTN connectivity, cost and maintainability.…