MICROWAVE REPEATER RESEARCH 



243 



When the equahzers were added, the pulse shapes shown in the second row 

 were not greatly changed for variations of ±3 megacycles or more in the 

 intermediate frequency. 



In concluding this section it should be noted that when the various com- 

 ponents were connected together to form an IF-type repeater amplifier, 

 it was found that the amplitude and phase characteristics added as expected 

 and resulted in a satisfactory amplifier with only a few millimicroseconds 

 variation in delay and only a few tenths of a db variation in amplitude over 

 a 10-megacycle band. Nevertheless, the equipment is very complicated. 



1 TIME 



10 TIMES 



30 TIMES 



AMPLIFIER WfTH EQUALIZER 

 Fig. V-20. — Results of circulated pulse tests on IF amplifier. 



A straight-through radio frequency amplifier repeater is still to be desired 

 and, no doubt, further research will eventually produce such an amplifier. 



VI. The Complete Repeater* 



In the preceding section it has been pointed out how the various compo- 

 nents that make up the repeater amplifier were added together without the 

 introduction of additional distortion. The antennas, filters and amplifiers 

 which go to make up one of the complete repeaters shown in Fig. II- 1 were 

 designed with the same ease of interconnection in mind. However, as will 

 be discussed below, the length of the waveguide lines used for these connec- 

 tions has an important bearing on the distortion introduced. 



The large amount of equipment in the repeater amplifier makes it 

 desirable, from the maintenance standpoint, to locate the amplifier near 

 the ground and to provide towers for the antenna where antenna elevation 



* Prepared by D. H. Ring. 



