Abstract.
The features of matched filtering of
linearly frequency modulated broadband signals (LFM) with a minimum number of
performed arithmetic operations are considered. For this, the sum of the
transfer function is represented as a double, embedded one into another, with the
subsequent reduction of one of them to a simple algebraic expression. In this
case, the number of arithmetic operations reduces dramatically, while the
numerical value of the filter response remains unchanged.
Methods are proposed and the conditions are determined for turning
the transfer function of the LFM signal compression filter to a recursive form.
In addition, the possibility of increasing the clock frequency is taken into
account, which in some cases is necessary to reduce losses in digital
processing, because in general, any time-limited signal has an infinitely
decreasing spectrum. The estimation of the computational efficiency of the developed
methods is given, which increases with the growth of the base of the chirped
signal during its processing, and the trend of radar development is moving in
the direction of increasing the complexity of the probe signal, i.e. increasing
its base. The simulation is presented, confirming the identity of the chirped signal
compression results similar to the processing in a compression filter with a
recursive transfer function. At the same time, the hardware (software) costs
reduced by five times for the implementation the chirped signal compression
operation with a base of 100. This allows you to reduce the hardware
and dimensional characteristics of equipment, it’s power consumption and at the
same time reduces processing time and improves reliability.
Keywords: radiolocation,
matched filtering, broadband signal, transversal filter, recursive filter.
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