Austar picks Nortel for regional WiMAX rollout

Stuart Corner
Thursday, 21 June 2007 08:22

Business IT - Networking

According to Inshaw, "We have chosen to invest our R&D into the mobile WiMAX because that is where we think the volume will be in the market. Specifically Nortel believes that alternative telco operators seeking to compete with incumbent fixed and cellular operators will be a key market, and the needs of this market are driving its WiMAX product development."

He also said: "We are skipping wave one [of IEEE802.16e] and going straight to wave 2 which offers two options, MIMO or beam forming (aka adaptive antennas). We are the only ones doing MIMO, and we have some very good reasons for that."

He explained that MIMO significantly increases performance in three areas: coverage, capacity and throughput, adding "Most of our competitors are doing adaptive antennas in the first instance."
 
MIMO technology uses multiple antennas on the base station and terminal to transmit the data over multiple paths simultaneously, thereby increasing performance. With beamforming the base station antennas constantly focus the RF energy on each terminal in their coverage area. The 802.11e standard requires the terminal devices to support but options.

Navini claims to be the only WiMAX manufacturer supporting both systems in its base stations. However, according to Inshaw, the capital and operating costs of beam forming systems are significantly higher. "Adaptive antennas need electronics in the antenna up the mast, they are generally larger and need four to eight feeder cables to each antenna so there are a lot of capital and operating costs. For example if the electronics up the tower fails it probably costs five to seven thousand dollar to send someone to fix them....MIMO antennas are smaller and lighter and don t put the same [physical] load on the towers."