Contents
Why do radars use chirps?
The chirp pulse compression process transforms a long duration frequency-coded pulse into a narrow pulse of greatly increased amplitude. It is a technique used in radar and sonar systems because it is a method whereby a narrow pulse with high peak power can be derived from a long duration pulse with low peak power.
What does pulse compression do?
18.6 Pulse Compression The goal of pulse compression is to transmit a long duration pulse of high energy, but to detect a short duration pulse to localize the receive filter output response to one or at most two radar range bins. Early radars accomplished this by transmitting a signal with linear frequency modulation.
Is it possible to see pulse compression gain?
If you really want to see pulse compression gain, then you’ve gotta compare something different. Indeed, the subject of pulse compression is usually introduced by explaining the tension between time resolution and S N R, before pulse compression.
How is the compression of a chirp signal matched?
In general, the compression process is a practical implementation of a matched filter system. For the compression filter to be matched to the radiated chirp signal, its response is the complex conjugate of the time inverse of the transmit filter’s impulse response.
Why does SNR gain vary by pulse shape?
The SNR gain achieved will vary widely by pulse shape, because they will have different frequency responses. All that is guaranteed with a matched filter is that the SNR will be maximized over all possible receive filters for a given transmit filter.
How is signal detection enabled by pulse compression?
Implemented electronically, one can say that receivers measure voltage. Detection is enabled by the boost in the ratio of Signal voltage (increased by 10 dB thanks to pulse compression) to Noise voltage (unchanged by pulse compression).