Page 168 - DCAP311_DCAP607_WIRELESS_NETWORKS

Wireless Networks

Notes The WiMAX Forum-Interoperability for 802.16 Compliant Systems
Establishment of a standard is critical to mass adoption of a given technology; however by itself a
standard is not enough. The 802.11b WLAN standard was ratified in 1999, however it did not reach
mass adoption until the introduction of the WiFi Alliance and certified, interoperable equipment
was available in 2001. In order to bring interoperability to the Broadband Wireless Access space,
the WiMAX Forum is focused on establishing a unique subset of baseline features grouped in
what is referred to as “System Profiles” that all compliant equipment must satisfy. These profiles
and a suite of test protocols will establish a baseline interoperable protocol, allowing multiple
vendors’ equipment to interoperate; with the net result being System Integrators and Service
Providers will have option to purchase equipment from more than one supplier.
Profiles can address, for example, the regulatory spectrum constraints faced by operators in
different geographies. For example, a service provider in Europe2 operating in the 3.5 GHz band,
who has been allocated 14 MHz of spectrum, is likely to want equipment that supports 3.5 and/
or 7 MHz channel bandwidths and, depending on regulatory requirements, TDD (time-division
duplex) or FDD (frequency-division duplex) operation. Similarly, a WISP (Wireless Internet
Service Provider) in the U.S. using license-exempt spectrum in the 5.8GHz UNII band might
desire equipment that supports TDD and a 10 MHz bandwidth.
WiMAX is establishing a structured compliance procedure based upon the proven test
methodology specified by ISO/IEC 9646.3 The process starts with standardized Test Purposes
written in English, which are then translated into Standardized Abstract Test Suites in a language
called TTCN.4 In parallel with the Test Purposes, the Test Purposes are also used as input to
generate test tables referred to as the PICS (Protocol Implementation Conformance Statement)
Proforma is generated. The end result is a complete set of test tools that WiMAX will make
available to equipment developers so they can design-in conformance and interoperability during
the earliest possible phase of product development. Typically, this activity will commence when
the first integrated prototype becomes available.

Self-Assessment

Fill in the blanks:
1. The .................................... MAC relies on a Grant/Request protocol for access to the medium
and it supports differentiated service levels
2. The .................................... standard is designed for optimal performance in all types of
propagation environments, including LOS, near LOS and NLOS environments,

3. The first version of the 802.16 standard released addressed Line-of-Sight (LOS) environments
at high frequency bands operating in the .................................... range
4. Satisfying the growing demand for BWA in underserved markets has been a continuing
challenge for service providers, due to the absence of a truly .................................... standard.



Case Study Redline Debuts its 802.16-2004 Compliant Broadband
Wireless Solution at WCA Symposium

About Redline Communications
Redline Communications is a technology leader in the design and manufacture of standards-
based broadband wireless access solutions. Using industry leading OFDM technologies,
Redline’s award-winning products provide unmatched high capacity and non-line-of-
sight capabilities with proven performance, reliability and security. Ideal for a variety of
Contd...

162 LOVELY PROFESSIONAL UNIVERSITY