Ericsson MINI-LINK E, Техническое описание

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MINI-LINK E and E Micro
Multiplier (MCM)
The VCO signal is amplified and frequency multiplied (2 or 4 times depending
on the frequency band).
Power Amplifier (MCM)
Adjusting the gain of the power amplifier controls the transmitter output power.
The output power is set in steps of 1 dB through the operation and maintenance
system. The transmitter can be switched on or off by switching the final amplifier.
4.5.4 Output Level Control
The output signal level from the final amplifiers are analyzed in order to see if
transmitted power is within specified range (output power alarm).
4.5.5 Receiver Block
The received signal is fed from the input branching filter into a low noise
amplifier and a down-converter to the first IF of 974 MHz (Receiver MCM). After
bandpass filtering and amplification, the signal is down-converted to the second
IF of 140 MHz (IF Converter). A portion of this 140 MHz is used in the RSSI.
The 140 MHz signal from the IF Converter is amplified and fed to the modem
board. This double down-conversion with a high first IF enables frequency
selection over a wide frequency band, with excellent receiver spurious and
image rejection.
Receiver Oscillator and Multiplier (MCM)
The local oscillator signal used in the first down-conversion is generated in the
same way as for the transmitter oscillator. The signal is multiplied (2 or 4 times
depending on channel frequency) and amplified.
4.5.6 IF Oscillator
The oscillator consists of a Phase Locked Loop (PLL) and a VCO. It is used for
the second down-conversion to 140 MHz. The VCO is also used for adjustment
of the received 140 MHz signal (through a control signal effecting the division
number in the PLL).
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AE/LZT 110 2012 R8C 2002-03-04