The area to be covered using DMR technology is divided into number of cell sites.Įach cell site consists of one or more than one Base Stations (BSs).Įach Base Station can be interfaced with LAN using IP swithes or with WAN using routers.
The figure-2 depicts DMR network architecture.Īs shown DMR consists of two main elements Base station and portable subscriber radio units. time slots).įurther, logical channel can be further categorized into traffic channel and control channel based on Hence DMR channels are of two types physical channel (i.e. Control channel can also be used to transmit short data messages in case Informations to DMR portable subscriber units. It periodically broadcasts useful system related
Manages and controls subscriber unit registration, call requests,Ĭhannel assignments etc. Traffic channel carries either voice or data information.Ĭontrol channel is used for various functions viz. In each physical channel, one logical channel is used for traffic and the other for control information. Hence there are two logical channels per physical channel. These slots are known as logical channels while frequency is known as physical channel. In the uplink and downlink bands, each channels consist of 12.5 KHz bandwidth each.Įach channel is further used at two different time slots using TDMA technique. TDMA (2 time slots per channel) FDMA vs TDMA➤īoth voice calls and data calls are supportedĤ state FSK, 4 possible symbols, 4800 symbols/sec, 9600 bits/sec, ASK vs FSK vs PSK➤.FDMA (one band for uplink side and other band for downlink side),ġ pair of frequencies used for Tx/Rx direction.66 to 960 MHz for DMR Tier-II and Tier-III
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