Method and apparatus for reducing interference in a time division duplex communication system

A first transmitter which reduces an interference in a time division duplex (TDD) communication system having the first transmitter, a second transmitter, and a receiver, wherein the first transmitter alternates between a transmit state in which a first information signal having a first bandwidth is transmitted and a standby state in which a residual signal is transmitted, and wherein, during the standby state of the first transmitter, the second transmitter transmits a second information signal having a second bandwidth smaller than the first bandwidth, and wherein the receiver has a composite pass band having a bandwidth substantially equivalent to the second bandwidth, the first transmitter comprising:

• a transmitter section which transmits the first information signal and the residual signal, said transmitter section comprising:
• a power amplifier to amplify the first information signal and the residual signal to a power level;
• and
• an exciter to control a carrier frequency of the first information signal and the residual signal;
• and
• a controller which is coupled to said power amplifier and said exciter, for adjusting the power level to a residual power level and for offsetting the carrier frequency outside the second bandwidth and within the first bandwidth during the standby state.

A first transmitter which reduces an interference in a time division duplex (TDD) communication system having the first transmitter, a second transmitter, and a receiver, wherein the first transmitter alternates between a transmit state in which a first information signal having a first bandwidth is transmitted and a standby state in which a residual signal is transmitted, and wherein, during the standby state of the first transmitter, the second transmitter transmits a second information signal having a second bandwidth, and wherein the receiver has a composite pass band having a bandwidth substantially equivalent to the second bandwidth, the first transmitter comprising:

• a transmitter section which transmits the first information signal and the residual signal, said transmitter section comprising:
• a power amplifier to amplify the first information signal and the residual signal to a power level;
• and
• an exciter to control a carrier frequency of the first information signal and the residual signal;
• and
• a controller which is coupled to said power amplifier and said exciter, for adjusting the power level to a normal power level, modulating the first information signal with outbound message information, and setting the carrier frequency of the first transmitter within the second bandwidth when the first transmitter is in the transmit state, and for adjusting the power level to a residual power level, modulating the residual signal with a predetermined signal, and offsetting a carrier frequency of the first transmitter to move the residual signal outside the second bandwidth when the first transmitter is in the standby state.