Patent SU-711849-A1 (SU)
Title: Device for suppression of background noise
Inventor: POPOV D I
IPC: G01S13/52
Filed: 1977-11-25
Granted: 1998-11-27
Abstract: FIELD: radio engineering. SUBSTANCE: device has serial circuit of unit measuring and averaging inter-period noise phase shift and smoothing filter, and two channels each of which has serial circuit of memory unit and subtraction unit, which second input is connected to input of memory unit. Input and output of memory unit of first channel is connected to first and second inputs of unit measuring and averaging inter-period noise phase shift. Third and fourth inputs of unit measuring and averaging inter-period noise phase shift are connected respectively to input and output of memory unit of second channel. Goal of invention is achieved by introduced serial circuit of unit, which calculates total noise phase shift, and function generator. In addition each channel has first and second multipliers and adder. First inputs of first and second multipliers are connected. Output of first multiplier is connected through adder to input of memory unit. Output of second multiplier of one channel is connected to second input of adder of another channel. Output of smoothing filter is connected to input of unit for calculation of total noise phase shift. First and second outputs of function generator are connected respectively to second inputs of first and second multipliers of each channel. Second claim of invention discloses device design in which unit measuring and averaging inter-period noise phase shift has serial circuit of dividing unit, function generator and logical unit, and two channels, each of which has serial circuit of first averaging unit, first multiplier, adder and accumulation register, and serial circuit of second averaging unit and second multiplier. Output of first averaging unit of first channel is connected to second input of first multiplier of second channel, which first input is connected to second input of second multiplier of second channel, which first input is connected to second input of first multiplier of first channel. Output of second multiplier of each channel is connected to second input of adder of another channel. Output of accumulation registers of first and second channels are connected to respectively first and second inputs of dividing unit and second and third inputs of logical unit. In addition first and second and fourth and third inputs and output of unit measuring and averaging inter-period noise phase shift are respectively inputs of first and second averaging units of first and second channels and output of logical unit. Third claim of invention discloses device design in which unit for calculation of total noise phase shift according to claim 1 has serial circuit of adder, normalization unit, and memory unit. Output of memory unit is connected to second input of adder. Input and output of this unit are first input of adder and output of normalization unit. Fourth claim of invention discloses device design in which smoothing filter has serial circuit of weight unit and accumulation unit. Input and output of smoothing filter are respectively input of weight unit and output of accumulation unit. EFFECT: increased precision of Doppler shift compensation.