A high performance point-to-point modem for the ITS 220 MHz spectral allocation

Five narrowband frequency pairs in the 220-222 MHz land mobile band have been allocated for applications in intelligent transportation systems (ITS). Low rate data communications in the range of 4 to 30 kbps can be supported on these 4 kHz channels. This paper is the result of an ongoing project to design, construct, and field test a high performance wireless modem architecture for application in the ITS spectrum allocation. Here we concentrate on an architecture optimized for stationary point-to-point applications. Field testing of this modem architecture has demonstrated that bandwidth efficiencies in excess of 5 bps/Hz are achievable at bit error probabilities of around 10/sup -5/. The experimental system which has been built serves as an effective testbed for further advances in narrowband wireless communications and for ITS application development.