MOBILE RADIO TRANSMISSION 



1081 



14 16 18 20 22 24 26 



DISTANCE FROM TRANSMITTER IN MILES 



Fig. 11 — Median r-f path losses along selected routes, (a) On a radial through 

 Dover, (b) On a radial through New Rochelle. 



comparison of frequencies is different at different locations. The "crosses" 

 are the median values of these points, so placed that there are as many 

 points above as below. The points for 3700 mc are taken from the data 

 of Fig. 10. The crosses of Fig. 1 are considered to be the most reliable 

 all-aroiuid comparison of propagation at the different frequencies. 



RELATION OF SPEECH-NOISE RATIOS TO R-F SIGNAL POWER 



Speech-to-noise ratios were measured at all of the test locations by the 

 use of the level distribution recorder as described earlier. During the 

 course of any given test the audio noise from the receiver varied con- 

 siderably and these variations were recorded on the LDll. It was found 

 by correlation between subjective observations of circuit merit and the 



