Saturday, April 21, 2012

Some Thoughts on Bandwidth

The NY Times has recently reported on wireless that the carriers are seeking more bandwidth. They state:

The wireless carriers say that in the next few years they may not have enough of it to meet the exploding demands for mobile data. The result, they ominously warn, may be slower or spotty connections on smartphones and tablets. They imply in carefully couched language that, given the laws of supply and demand, the price of cellphone service will soar. 

I would suggest several observations:

1. With the change from QPSK to OFDM we have gone from 1 bps/Hz to almost 10 bps/Hz.

2. With smart antennas we will go from 10 bps/Hz to over 100 bps/Hz.

3. At the same time data rates for video using MPEG X, 4 to 5, we see rates for HDTV dropping from 20 Mbps to 4 Mbps to 2 Mbps.

So as capacity increases and as demand decreases where is the gap?

Somehow this set of simple facts was missing from the article, and from the carriers as well.