| 摘要 |
An interference avoidance system used in conjunction with a vehicular target detection system. The microwave transceiver section of the vehicular target detection system, in which the present invention is incorporated, transmits and receives time-multiplexed microwave signals having at least two channels (frequencies) spaced about 250 kHz apart. The time-multiplexed transmit signal is transmitted and strikes objects (targets) in the environment, and a portion of the transmit signal is reflected back the antenna. A difference signal having a frequency equal to the difference between the frequency of the transmit and the received signal is generated, digitized, and a Fast Fourier Transform (FFT) is performed on the digitized difference signal. A microcontroller analyzes the energy spectrum to determine whether there is interference present. If such interference is present, the microcontroller causes the transmit frequency to change until a frequency is found which is relatively free of the interference. |
