The efficiency of spaced reception under linear addition with account taken of the imprecision of phasing of added signals
Abstract
The paper considers the use of spaced reception to improve the reception of optical waves which fade during propagation of the earth's atmosphere. To aid in the analysis of the efficiency of spaced reception, the ensemble average of the signal/noise ratio is obtained, and the effect of phase fluctuations (caused by atmospheric turbulence) on this ratio is studied. The phase fluctuation can be described in terms of normal laws of distribution. It is found that the reduction of the ensemble average of the signal/noise ratio for linear addition of waves does not exceed 0.5 for various distribution laws for the envelope and that this reduction weakly depends on the correlation coefficient. For paths, where the fluctuation of phase differences does not exceed pi/2, the efficiency of linear addition of fields of spaced waves is higher than it is during conditions of power additions.
 Publication:

Radiotekhnika
 Pub Date:
 December 1977
 Bibcode:
 1977RaT....32Q..45M
 Keywords:

 Adding Circuits;
 Linear Receivers;
 Optical Communication;
 Phased Arrays;
 Reception Diversity;
 Signal Reception;
 Signal To Noise Ratios;
 Apertures;
 Correlation Coefficients;
 Entire Functions;
 Phase Deviation;
 Photometers;
 Rayleigh Distribution;
 Signal Fading;
 Communications and Radar