Investigation into network architecture and modulation scheme for MIL‐STD‐1773 optical fiber data buses

Abstract

The design issues on network architecture and modulation scheme that can be used to implement reliable MIL‐STD‐1773 avionics optical fiber data buses are discussed. Both single‐star and multi‐star architectures are presented to such optical fiber data buses. Several network configurations based on passive and/or active coupling components are also considered, and they are compared in terms of system complexity and reliability. Moreover, three modulation schemes are presented, i.e. partial trilevel Manchester II bi‐phase coding, extended Manchester II bi‐phase coding with beginning‐stopping flags, and pseudo‐four‐ary pulse width modulation, respectively. Their use can feasibly solve the problem associated with fast identification of correct operation states of an active transmitter at the output of optical receivers.