Speculation on my part. But being an Amateur Radio Operator I would strongly suspect that a relay/repeater system would be employed to provide a decent signal while deep underground.
Doesn't explain how the security forces would communicate during an emergency while underground.
VHF/UHF handheld radios would be marginal in a subway.
posted on 01/18/2007 7:35:11 PM PST
(Don't hit them between the eyes. Hit them right -in- the eyes!)
Couldn't/wouldn't there be separate repeaters for GSM frequencies and VHF/UHF frequencies?
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