User Manual

sTRU Single Transceiver Unit
4.2 DSP System
The DSP System performs all baseband signal processing. For downlink,
this includes Terrestrial Protocol Handling (TPH), encoding, ciphering and
burst generation. For uplink it includes equalisation, combining, decoding,
deciphering and TPH.
4.3 Radio Control System
The functions of the Radio Control System are the following:
• Synchronises and controls the different parts of the radio
• Modulises and D/A converts the data to transmit
• Filters the received radio signal with a channel selective filter
• Compensates the RX and TX delays and gain variations
The Radio Control System is seen by the rest of the RBS as the front end
to the radio, which can be asked to transmit a burst of data using a selected
modulation, or asked to receive a burst using a selected digital filter.
All the time critical radio control functions are performed by the Radio Control
System and no computational support is required from the CPU system on
real time basis.
4.4 Radio System
The Radio System contains a radio receiver, a radio transmitter and a power
amplifier.
The radio receiver receives RF modulated uplink data from 1 or 2 diversity
branches and sends it to the Radio Control System.
The radio transmitter generates the RF downlink signal from the modulated
baseband signal. It sends the RF signal to the power amplifier. The power
amplifier then amplifies the downlink RF signals.
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EN/LZT 720 0349 Uen R3A