Title
256 QAM Modem for High Capacity Digital Radio System
Abstract
This paper presents topics related to the 256 QAM modem for high capacity digital microwave radio. Specifications for modem circuitry are derived from the allowable carrier-to-noise ratio degradation point of view. In this process, various degradation factors are categorized so that the same evaluation is possible. Two representative circuits, the automatic threshold control (ATC) and carrier recovery circuits, of particular importance for developing a 256 QAM modem, are presented. For the ATC circuit, the operation principle as well as the presence of the false-lock phenomenon and its evasion method are described. The prototype 256 QAM modem performance indicates the prospect of a 400 Mbit/s 256 QAM modem.
Year
DOI
Venue
1986
10.1109/TCOM.1986.1096616
IEEE Transactions on Communications
Keywords
Field
DocType
microwave radio communication,quadrature amplitude modulation
Quadrature modulation,Digital radio,Quadrature amplitude modulation,Data transmission,Computer science,Carrier recovery,Microwave transmission,Automatic control,Electronic engineering,Amplitude modulation
Journal
Volume
Issue
ISSN
34
8
0090-6778
Citations 
PageRank 
References 
10
7.92
5
Authors
2
Name
Order
Citations
PageRank
Yoichi Saito12616.28
Yasuhisa Nakamura24412.62