Intelligent automatic gain control circuit

DETAILED DESCRIPTION The present invention relates to a technique and apparatus relevant to systems such as the U.
S.
Navy Link-11 and Link-14 computer-to-computer systems and to any other computer-to-computer communications system in which a station address message precedes the actual message.
The fact that the station address message contains information advising all receiving stations in the network which station will transmit next is utilized in accordance with the present invention to preset the AGC voltage in the receiver to that level that is compatible with the amplitude of the last signal that was transmitted from the aforesaid next station to transmit.
In accordance with the teachings of the present invention means are provided, preferably at each station in the network, for entering into and reading out of a continually updated memory signal level and gain level information, respectively.
The updated memory is thereby available for readout of the strength of the signal that was previously received from the next transmitter to transmit.
This readout is then used to adjust the AGC circuits of the receiving stations.
It is readily apparent, therefore, that by utilization of the technique disclosed herein the receiving stations will undergo smaller and less time consuming excursions in the setting of the AGC circuits thereof.
The natural consequences of this technique are the prevention of loss of data and the increase of system throughput.
A priori information is thus used to determine which network station will transmit next and how strong the signal from that station was the last time that station transmitted.
Further, in accordance with the present invention, to account for the situation where the next station to transmit has never transmitted before, the memory at the receiving stations may be preprogrammed to set an arbitrary AGC voltage level for reception from such transmitter.
When that transmitting station comes on, each receiving station will have a stored value in memory for commensurately adjusting its own AGC circuit