Abstract: One data stream is input to a radio frequency (RF) input terminal of a first receiver interface circuit, and the second bit stream is applied to an RF input terminal of a second receiver interface circuit. Each of the receiver interface circuits includes a Reed-Solomon frame synchronization, forward error correction and derandomizer module receiving the bit stream pattern from the RF terminal of the ground station. Following processing in the derandomizer module, the bit stream is input to a wide band frame synchronization module for synchronization on byte-aligned synchronization pattern at the beginning of each wide-band communications block frame. When synchronization has been established, the data frames are collected for transfer to a memory buffer module. Data buffered in the memory buffer module is direct memory access transferred by a VERSA Module Eurocard (VME) bus interface module to the satellite ground station.

Abstract: A wafer-scale integrated circuit comprises a few hundred modules which can be connected into a long chain by commands sent from a terminal XMIT to the modules along a transmit path set up by way of module inputs from neighbouring modules and outputs thereto, only one of which is enabled by one of four selection signals. The transmit path normally follows a route through a main chain of modules M0 to M15, as shown by a full line. However, commands may be sent to nodal modules M0, M6 and M10 to make a alternative direction selections thereat, so as to obtain access to modules M16 etc in spur chains. Commands are addressed to the modules in accordance with their distances F from XMIT. Spurs may themselves include nodal modules such as M17. The normal and alternative direction selections are listed in a stored table which is used by a command unit to access any desired module and then restore the main chain M0-M15.