Here I write on article How Wimax works and on wimax terminology
ASN – Access Service Network. Establish layer 2 connections between the BS and the MS. Transmit AAA messages to the home NSP of the MS. Assist the high level to establish layer 3 connections with the MS and assignthe IP addresses. Perform the radio resource management (RRM). Perform the intra-ASN mobility management and handover. Perform … Read more
The initial range is the process of estimating the distance or propagation time between a transmitter and a receiver. Area information can be used to assist in setting operating parameters for the transmitter and receiver. Since each MS has a unique distance from the base station, it is critical in the uplink to synchronize the … Read more
OFDMA is essentially a hybrid of FDMA and TDMA: Users are dynamically assigned subcarriers (FDMA) in different time slots (TDMA) . The advantages of OFDMA start with the advantages of single-user OFDM in terms of robust multipath suppression and frequency diversity. In addition, OFDMA is a flexible multiple-access technique that can accommodate many users with … Read more
The Difference Between Line Of Sight and Non-Line Of Sight Line of Sight (LOS): In LOS communication, there is a direct, unobstructed path between the transmitter and receiver. This type of communication is typically more reliable and offers higher data transfer rates because there are minimal obstacles in the signal’s path. LOS is commonly used … Read more
Fixed WiMAX offers cost effective point to point and point to multipoint solutions. What makes WiMAX so exciting is the broad range of applications it makes possible but not limited to broadband internet access, T1/E1 substitute for businesses, voice over Internet protocol (VoIP) as telephone company substitute, Internet Protocol Television (IPTV) as cable TV substitute, … Read more
How does WiMAX compare with the existing and emerging capabilities of 3G and Wi-Fi? The throughput capabilities of WiMAX depend on the channel bandwidth used. Unlike 3G systems, which have a fixed channel bandwidth, WiMAX defines a selectable channel bandwidth from 1.25MHz to 20MHz, which allows for a very flexible deployment. When deployed using the … Read more
Naturally, the first application for which a wireless alternative was developed and deployed was voice telephony. These systems, called wireless local-loop (WLL), were quite successful in developing countries such as China, India, Indonesia, Brazil, and Russia, whose high demand for basic telephone services could not be served using existing infrastructure. In fact, WLL systems based … Read more
Less complex modulation. OFDM is a simpler modulation technique that is better suited to deployments that do not require support for mobility. License-exempt bands. Mobile services require licensed spectrum to provide coverage in wide areas. Fixed deployments, however, have often successfully used license-exempt bands in areas where interference levels are acceptable. For this reason, most … Read more
The photo above shows the WiMAX radio deployed in an enclosure. Note from left to right: a) copper grounding cable on the inside of the enclosure b) Ethernet connection to the data source c) Heliax “pigtail” to the antenna (Heliax is a heavy duty, lightning resistant cable) d) 110v power via an APC UPS (note … Read more
At the core of WiMAX is the WiMAX radio. A radio contains both a transmitter (sends) and a receiver (receives). It generates electrical oscillations at a frequency known as the carrier frequency (in WiMAX that is usually between 2 and 11 GHz). A radio might be thought of as a networking device similar to a … Read more