LTE, Wimax and WIFI

I observed this particular trend in India with regards to household. People typically have a PSTN phone at their home provided by the local govt operator (BSNL). Then they use mobile phones from various operators. Though mobile phones are extensively used for communication I observed that people prefer wired telephones to convey important information to the other party whenever possible. Many are very comfortable with using a PSTN line. Though mobile communication is exploding PSTNs are doing very good business too. I was thinking if we could offer more services over wired line it would be big hit in India. At-least my mom would be very happy to talk to her sister over a video phone. VOIP phones?

On a same note I still dont find the wireless internet in India to be great. I recently got a Wimax connection and its kinda bad. First, the connection is costly and next the speeds are bad. More over the webauth makes it worse when there are multiple computers at home. The basic connection setup takes forever and it is really frustrating sometimes. Though companies have been pushing for wimax, end users are really not happy with it, at-least me and my friends are not happy with it. Now I always think how my fixed line (DSL) used to work. Its been a downgrade for me. Similar is the experience with the 3G modems. Worst uplink speeds and during peak hours you hardly get anything. The point here is Wimax and 3G are still not proving to be perfect replacement for the wired connections.

Recently I came across a service provider providing wifi services. The adds display 4G enabled technology and gives away words like MIMO and OFDM. It caught my interest and was wondering for a while what the underlying technology could be. Guess what its our humble Wifi. I was always a fan of WIFI and with latest 802.11n its time to explore the wifi mesh networks. About 3 years back, when I was in college, I happened to listen to a lecture from a professor who came all the way from Israel. The lecture was on Wifi mesh networks and various routing algorithms involved in it. Typically a wifi mesh is formed of multiple adhoc networks. The lecture was quite interesting and we did some experiments with our laptops and could route packets through multiple laptops. It was fun but I never thought it would be commercially launched (college kid, lack of experience :-)) Now when I see the add, it reminds me of the lecture and experiments. 802.11n on the backhaul and supported 802.11a/b/g towards the customer end seems great. Backhaul is powered with MIMO and OFDM which provide high speeds between the nodes can help boost the network performance. But again the network has to be carefully designed and routes to the main node are to be optimally configured. I quite dont know how the network is really performing, should talk to someone who is using the mesh, but I am quite happy to see wifi growing. Imagine if these networks grow then wimax and mobile networks can get in trouble. More over this wifi mesh is seeming to be a lot cheaper than what other technologies are offering.

Just a thought!

LTE vs Wimax : Myths and Realities

I was browsing through today and landed up at a discussion forum of Sprint Nextel. The post clears out the myths associated with LTE and Wimax and their convergence etc etc. The post is dated back to May 2008. The post tends towards Wimax since Sprint is largely deploying Wimax I suppose. Here are few myths and realities directly from the discussion page:

Myth: LTE is backwards compatible with 3G.
Reality: Strictly speaking, backwards compatibility implies that a 3G device can connect to an LTE base station. This is categorically not the case. LTE requires new base stations and new client devices. An HSPA handset will not be able to connect to an LTE base station, period.

Myth: LTE performance is better than WiMAX.
Reality: Because LTE & WiMAX are both based upon OFDMA-MIMO, there is not expected to be a significant performance delta over time. Because WiMAX will have been deployed commercially for over two years before the first LTE network is deployed in 2010, it may have superior performance initially.

Myth: LTE is an evolution of HSPA (3G)
Reality: The 3G evolution from WCDMA to HSPA was achieved via upgrades to operators’ existing 3G networks. LTE is not a 3G upgrade -- it must be deployed in new spectrum and requires a new radio access network (base station hardware, client devices) and connection to a new “all IP” core network (different from today’s 3G core networks.)It is possible to add LTE to existing 2G, 3G cell sites

Myth: Operators will replace their existing 2G/3G networks with LTE.
Reality: We expect operators to maintain their existing 2G or 3G networks for the foreseeable future. These networks are very efficient for voice and have built up good coverage over the years. Similar to WiMAX, LTE will initially be deployed as an overlay data network in
new spectrum. Operators will offer multi-mode handsets (e.g,. HSPA + LTE or HSPA + WiMAX) to provide the best of both worlds (coverage + high speed) to their subscribers while they build out their 4G networks over several years.

Myth: WiMAX & 3G are competitors
Reality: We expect WiMAX & 3G to be complementary. Whereas the circuit-switched voice offered by 2G & 3G networks is very efficient, WiMAX provides about 3x more data capacity than today’s 3G networks. This means operators can maintain their existing 2G or 3G network for voice & narrower-band data, and deploy WiMAX for more data intensive
applications.

Myth: WiMAX will not have as big a device selection as LTE
Reality: Even with the very first commercial Mobile WiMAX network in So. Korea, we’ve already seen a level in the variety of devices which exceeds that available for 3G today. For example, one of the most popular form factors for accessing the Wibro network are WiMAX USB
dongles with integrated MP3 players and/or storage. PC economics and innovation are backing WiMAX -- so one shouldn’t apply a traditianal “telecom” device model when comparing WiMAX & LTE. We also expect the M-Taiwan initiative and the KDDI consortium in Japan to help drive a level of device innovation not seen before for a new wireless technology.

Myth: WiMAX & LTE are going to converge.
Reality: Because WiMAX & LTE are so similar, some believe the two should converge. We’re not sure if such convergence will ever get traction, but for now, mobile WiMAX is two to three years ahead of LTE in terms of major commercial deployments and is moving full steam
ahead.

The detailed post with comments can be found here.