| 摘要 |
<p>PURPOSE:To obtain a picture of high image resolution which is free from a range error, by providing a temperature detector to an SAW decentralized delay line to form an accurate matched filter for a chirp signal used for picture processing. CONSTITUTION:For a mixer 3, a CW signal f11 delivered from a frequency synthesizer 2 is cut away by the gate signal g1 of the output of a synchronizing signal generator 6, and the pulse modulation is applied. The impulse, i.e., the output signal of the mixer 3 is supplied to an SAW decentralized delay line 4, and then a chirp signal having a long pulse width is outputted. For a mixer 7, the chirp signal of the output of the line 4 is cut away by the gate signal g2 of the output of the generator 6. A temperature detector 5 measures the center frequency of the output signal of the mixer 7 by measuring the temperature of the line 4 and feeds it to an SAR picture processor 12 on the ground as a temperature monitoring signal 14. On the ground area, the information on an accurate center frequency of the chirp signal and the changing factor of frequency is obtained by means of the monitoring signal 14, and a matched filter is formed for SAR reception signal. Then the picture is processed.</p> |
