Experiments on the Regeneration of 

 Binary Microwave Pulses 



By O. E. DeLANGE 



(Manuscript received September 7, 1955) 



A sifnple device has been produced for regenerating binary pulses directly 

 at microwave frequencies. To determine the capabilities of such devices one 

 of them was included in a circidating test loop in which pidse groups were 

 passed through the device a large number of titnes. Residts indicate that 

 even in the presence of serious noise and bandwidth limitations pidses can 

 be regenerated many times and still shotv no noticeable deterioration. Pic- 

 tures of circulated pidses are included which illustrate performance of the 

 regenerator. 



INTRODUCTION 



The chief advantage of a transmission system employing Ijinary pulses 

 resides in the possibility of regenerating such pulses at intervals along 

 the route of transmission to prevent the accumulation of distortion due 

 to noise, bandwidth limitations and other effects. This makes it possible 

 to take the total allowable deterioration of signal in each section of a 

 long relay system rather than having to make each link sufficiently good 

 to prevent total accumulated distortion from becoming excessive. This 

 has been pointed out by a number of writers. i-- 



W. M. GoodalP has shown the feasibility of transmitting television 

 signals in binary form. Such transmission reciuires a considerable amount 

 of bandwidth; a seven digit system, for example, would require trans- 

 mission of seventy million pulses per second. This need for wide bands 

 makes the microwave range an attractive one in which to work. S. E. 

 Miller* has pointed out that a binary system employing regeneration 

 might prove to be especially advantageous in waveguide transmission. 



1 B. M. Oliver, J. R. Pierce and, C. E. Shannon, The Pliilosophv of PCM, Proc. 

 I. R.E., Nov., 1948. 



'^ L. A. Meacham and Iv Peterson, An Experimental Multichannel Pulse Code 

 Modulation System of Toll Quality, B. S. T. J., Jan. 1948. 



' W. M. Goodall, Television l)y Pulse Code Modulation, B. S. T. J., Jan., 1951. 



* S. E. Miller, Waveguide as a Communication Medium, B. S. T. J., Nov., 1954. 



67 



