Abstract. Active radar
uses pulsed probing signals whose power and spectral characteristics determine
the main parameters of the radar station. These primarily include the detection
range, resolution and detection of weak signals against the background of
powerful ones. The power of the emitted signals increased to achieve these
goals, but this obtained by increasing their duration and bandwidth due to
technical limitations in amplitude and secrecy requirements. Therefore, as
probe pulses, signals with linear frequency modulation (LFM) are used, the
deviation of which determines the resolution. The multiplication of the band by
the duration is called the base for pulsed signals and its numerical value, as
well as the sampling frequency, defines the hardware and software
implementation of the digital compression filter in the receiver, since they
determine the number of arithmetic operations in the algorithm of the matched
filter. Therefore, it is necessary to increase it within reasonable limits by
no more than 1.5 ... 2 times, since further increase in the sampling rate is
not effective due to the decreasing spectrum of the LFM signal. In addition,
weighting performed while compressing chirp signals, which can be implemented
both in the time and in the frequency domain. It is most appropriate to
implement it in the time domain from the point of hardware implementation, as
well as the ability to use it in a channel with correlation-filter processing.
So, the peculiarities of weight processing in the time domain of discrete,
compressed chirp signals are considered, the sampling frequency of which
exceeds the signal frequency deviation. The conditions determined for the
formation of coefficients of the weight filter for the block diagram under
consideration. The estimation of computational efficiency and the simulation
results presented.
Keywords:
radio-location, weight processing, side lobes, sampling rate, Hamming weighting
function.
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