DocumentCode
1968591
Title
11 and 15 GHz PCM Radio-Relay Systems
Author
Nishino, Kohei ; Hosoda, Akira ; Kubo, Shoji ; Mukai, Tadashi
Author_Institution
Radio Section, Engineering Bureau, Nippon Telegraph and Telephone Public Corporation, Uchisaiwai-cho, Chiyoda-ku, Tokyo, 100, Japan
fYear
1976
fDate
14-17 Sept. 1976
Firstpage
455
Lastpage
459
Abstract
This paper describes the 11 GHz and 15 GHz PCM radio relay systems, capable of conveying 65 Mb/s per radio channel, developed by Nippon Telegraph and Telephone Public Corporation NTT). The system employs 4-phase digital modulation and coherent detection. Radio equipment is fully solid-stated, using IMPATT diodes in the power amplifier. They are mainly. used for transmission circuits between telephone offices in large cities and for short haul transmission. The test results showed that compatible operation between 65 Mb/s PCM system and 2700 CH FDM-FM systems is possible, using the existing 11 and 15 GHz FDM-FM system frequency arrangement. These systems are now in use in 40 stations in Japan.
Keywords
Circuits; Digital modulation; Digital relays; Diodes; Phase change materials; Power amplifiers; Power system relaying; Radiofrequency amplifiers; Telegraphy; Telephony;
fLanguage
English
Publisher
ieee
Conference_Titel
Microwave Conference, 1976. 6th European
Conference_Location
Rome, Italy
Type
conf
DOI
10.1109/EUMA.1976.332317
Filename
4130983
Link To Document