I am logged into my office workstation over a Qualcomm CDMA (spread spectrum -- 1.25 MHz bandwidth) cell phone operating in the 1.9 GHz PCS band. The phone is plugged into the serial port on my laptop, and it's carrying TCP/IP/PPP packets from the Linux operating system on my laptop to the company Internet and thence to the outside world.

The cell site is perhaps a mile or two away on a 2-story building, and the phone is just resting on the top of my bag in a horizontal position. The path is not especially strong; I see only one bar on the signal strength meter. Yet thanks to the strong coding and inherent multipath resistance of spread spectrum, the TCP packet loss rate is nil -- even character-at-a-time typing works just fine.

Phil

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