Abstract: A system for convolutional interleaving of data bits in accordance with preselected convolutional interleaving parameters employs random access memory (RAM) and control thereof is provided by WRITE and READ column and row signals, which are generated responsively to the interleaving parameters and permit realization of the system with memory requirements slightly more than shift register interleavers but substantially less than hetertofore known RAM interleaver implementations. In one system embodiment, the system output data bits involve both RAM output and the incoming data bit. In another system embodiment, pseudo random convolutional interleaving is attained, again responsively to the preselected convolutional interleaving parameters. In either system, the parameters may be changed as desired to accommodate performance need.

Abstract: A system for effecting radio communication over a given range of frequency channels among a plurality of participating local stations, includes: a variably settable channel transmission unit at each such participating local station; and a controller or central station having an interference array processor for receiving data characterizing the system and each such participating local station for assigning datum channels (frequencies) to each such participating station with prescribed channel spacing and what is termed a "book-page generator" for compiling data in successive book pages of initial and subsequent channel assignments for stations, with maintenance of such datum channel spacing. Further data compilations are made from the book-page generator in what are termed "station pages", comprising frequency shift instructions specific to the stations. Since a station page is derived from plural book pages, any station may be compromised without revelation of the contents of the book pages.

Abstract: A method for effecting communication between first and second antennas, includes the steps of (a) mutually displacing the antennas and determining received signal strength at each antenna and positioning said antennas accordingly to obtain a first quality level of communication therebetween; and (b) effecting a second quality level of communication as between the antennas, exceeding the first quality level, by defining a plurality of succeedingly diminishing search movement patterns for each of the first and second antennas, transmitting from the first antenna while displacing the second antenna in one such pattern and detecting the level of receipt of such transmitted energy. The second antenna is now placed in its location of maximum received signal level and transmits while the first antenna is displaced in one of the patterns and its level of receipt of transmitted energy is monitored. The first antenna is now placed in its location of maximum received signal level.

Abstract: A communication system, adapted particularly for use in military tactical situations, includes a plurality of central stations and at least one remote station assigned to each such central station. Each central station includes an omnidirectional antenna and each remote station includes a directional antenna, directed toward the central station to which the remote station is assigned. Each central station transmits at a distinct frequency and each remote station assigned thereto receives at the frequency of its assigned central station and transmits at a different frequency, unique to itself. Transmission qualities between central stations is evaluated to optimize communication paths between remote stations.