Radio test performance of a narrowband TDMA system

Using TDMA transmission in digital cellular radio gives several advantages over conventional FDMA systems. However, TDMA implies a higher bitrate at each carrier and hence the multi-path fading will appear as frequency selective fading. This type of distortion destroys the function of a conventional demodulator. In this paper it is shown that a decision feedback equalizer can remove the intersymbol interference created by the frequency selective fading. The paper gives a description of the design of a narrowband TDMA experimental system, DMS 90. Experimental results from CEPT trials in Paris and from field measurements in Stockholm are also given for transmission rates of 340 and 170 kbps.