| 摘要 |
<p>PURPOSE:To eliminate malfunctioning due to a reflected wave from the surface of ground or sea, by expanding a frequency band of a transmitted wave with modulation thereof by a spectrum diffusion code to make the use of a radio wave conceal while avoiding effect of jamming. CONSTITUTION:As for the downward direction of a flying object, an oscillation frequency of a voltage control oscillator 20 for driving a code generator 21a is changed according to distance to the surface of ground or sea to vary a distance range to the surface of ground or sea. As for the upward direction thereof, an oscillation frequency of a clock oscillator 24 for driving a code generator 21b is kept constant to match the distance range with an effective range of a shell head of the flying object. Then, a frequency band of a transmitted wave is expanded with the modulation thereof by a spectrum diffusion ode to minimizing discovery by an enemy and even if jammed, an output of a video amplifier 6 for received signals is correlated with a code by one bit before and after a modulation signal by correlators 16a-16e. Thus, a jamming wave is diffused reversely to depart from a band of a Doppler filter.</p> |
