Patent ID: 7379446

Claim:
A method of operating a base station transmitter in a frequency division multiplexed communications system, the method comprising: transmitting first signals into a first region using a set of N tones to communicate information over a first period of time, said first period of time being at least two seconds long, where N is larger than 10; and transmitting during a second period of time a second signal including a set of X tones into said first region, where X is less than 5, and where less than 80% of a maximum average total base station transmission power used by said base station transmitter to transmit signals into the first region during any 1 second period during said first period of time is allocated to said set of X tones and each one of said X tones to which power is allocated receives at least 20 times the per tone average power allocated to tones during said any one second period.