MULTI-CHANNEL RADIO RELAY SYSTEMS

摘要

A multi-channel radio relay system in which various frequency channels are provided in a link between a transmitter and receiver is disclosed. The channels are combined to form a common, high-frequency group using a cascade circuit each branch of which has a circulator and a band-pass filter. The frequencies are allocated such that each channel passes via an equal number of circulators. The highest frequency is allotted to that circulator most remote from the antenna in the transmitting cascade and nearest the antenna in the receiver or vice versa. The highest frequency is allotted to the circulator which is disposed at a location of the cascade opposite to that allotted to the lowest frequency. All the circulators are similarly disposed in their respective cascades. The filter which is connected to the circulator which is most remote from the antenna in each cascade is detuned to present a centre frequency displaced in the direction of the centre frequency of the adjacent channel frequency. The system provides compensation for transit time distortion not only for the centre frequency channels but also for the edge channels.