Thursday, May 31, 2007

Towards WiMax




At last the government finally announced the "winners" of the so called WiMax spectrum tender on 16 Mar 2007. Three companies are given 30 MHz each of the 2.3 GHz spectrum. The other one is given with only 25 MHz to operate in Sabah and Sarawak as the spectrum is limited to 100 MHz only. There are not enough channels for four operators to operate at the same place without radio signal interferences.

The four now join the other companies who have been allocated 2.5 GHz spectrum which can also be used for WiMax. For 2.5 GHz spectrum, the total available frequency is 184 MHz which enables six operators to be allocated with 30 MHz each.

With this latest development, we may eventually have ten (10) WiMax operators in Malaysia. There will be plenty of choices for customers. This reminds me of the old mobile days when there were about ten mobile phone companies trying to start the service and get their market shares. At the end of the day only three survived. Are we going to see similar situation with WiMax operators? It may or may not happen. Only time will tell.

Any radio signal, including WiMax is subject to the same law of physics. It will get absorbed by water (in leaves of trees) and walls. It will be reflected by certain surfaces such as concrete wall. It suffers energy loss as it passes through the air or reflected by some objects in its path - lowering capacity with distance. There are so many factors to consider, which will affect the overall performance. Every geographic locality will be different. Hence, radio frequency analysis has to be made at every location. The advantage of WiMax compared to WiFi is that it can transmit higher power signal (due to licence spectrum) and can reach longer distance. As the distance increases, the required number of BTS will be reduced (for the same size of coverage area) and the cost of providing backhaul bandwidth gets lower. However, there is always a trade off between capacity and coverage.

Till these days, hype on WiMax is never ending. I still see media reports promising 50 Mbps bandwidth for up to 70 km radius of coverage. Such performance may be possible only if there is only one user using a WiMax base station which is going to be a very expensive proposition! WiMax cannot solve all broadband problems. There are limits of what it can do. If we can get to share 20 Mbps within up to two km radius, we should be ecstatic. With such performance, to provide 20% of coverage for the whole of Malaysia (with a total land area of 330,000 sq km) it would require at least 5,000 base transmission stations (BTS). If a BTS only manages to provide good coverage within one km radius, the figure would increase to a staggering 20,000 BTS. Assuming 10,000 BTS are required and each one would cost RM 250,000, the total investment would be RM 2.5 bil (excluding the end-user devices and civil works)! With a possibility of 2 mil subscribers, the cost per subscriber would be RM 1,250. But the margin of error in the number of BTS could be as high as 100%. [Note: The above figures are for illustration only.]. Does this make sense? I leave it to the readers to ponder.

Is there any certified WiMax product today? There are actually two types of WiMax. For fixed broadband (based on IEEE 802.16d-2004 standard) and for mobile broadband (based on IEEE 802.16e-2005 standard). So far only 12 manufactures with 28 fixed WiMax products have been certified by WiMax Forum. All of them are using 3.5 GHz spectrum. According to WiMax Forum, the mobile WiMax products are expected to get certification by mid-2007. Hence, no one has any certified mobile WiMax products today although some people claim to have pre-WiMax or Wi-Max-ready products. Whatever it is, WiMax interoperability tests are still on-going. I understand that some products have successfully been tested.

As for JARING, we do have 2.5 GHz spectrum which is currently being used for our wireless broadband services (JARING Flite Wireless) in Klang Valley. We believe it is the biggest such live service in Malaysia today. This system will be upgraded to mobile WiMax as soon as the product is certified. It will then be expanded and can be rolled out anywhere in the country. We look forward to serve the real WiMax to our subscribers.