Desarrollo de sistemas de recuperación de sincronismos para un modem FH TCM 8-DPSK basado en el TMS320C30

Abstract

In this paper we develop the synchronisation subsystems (carrier .frequency, symbol timing and unique word) for a Frequency Hopping-Trellis Coded 8-DPSK scheme for narrow band indoor mobile communications. The system implememation is based on a TMS320C30 Digital Signa/ Processor. An alldigital symbol timing recovery sysrem, which does 1101 require any oscillator, has been used. Dueto the use of a differemial scheme, only carrier Jrequency needs 10 be tracked. This is achieved by means of an alldigiral decision-direcred Automaric Frequency Comrol. A unique word is transmitted at the begining of every rime-slot 10 ensure rhar rhe receiver knows rhe righr insram where dara information comes.