AN/BRN-5 LORAN RECEIVER.

The BRN-5 described is a sensor, in that the data processing, filtering and logic functions are performed in the CP-890/UYK Central Navigation Computer. The hardware and software requirements are set by the performance required, which specifies search and settle times, track accuracy in noise and both synchronous and non-synchronous interferences, skywave rejection and a variety of other requirements. In addition, it is required to have an automatic overall self test capability, automatic fault isolation and a manual diagnostic mode. The system performance specification emphasizes reliability above all, not just hardware, but in the sense of accurate position information under the most severe signal environment conditions. This paper describes some of these techniques, along with parameter tradeoffs and unexpected phenomena uncovered in the course of system debug.