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4. Signal Flowchart in the Whole System
Reception
CN102 of the base unit is connected to the TEL line, and the signal is input through the bridge diode D118. While talking the
relay (Q110) is turned ON and amplified at the amplifiers Q103 and Q116, then led to BBIC (IC101).BBIC generates I and Q
signals by performing ADPCM conversion and QPSK modulation. These I and Q signals are mixed with pseudo random noise
code (PN code) to spread the spectrum, then TXI and TXQ signals are output. RFIC (IC301) outputs TXI and TXQ signals as
RF signal. The RF signal is passed through the filter (FL305) and amplified by 3 power amplifiers of Q303, Q302 and Q301,
then led to antenna switch (D301) and filter (FL304) to be transmitted from the antenna. As for the handset, RF signal from the
antenna is input to RFIC passing through filters of FL304 and FL301 to perform the de-spread, then input to BBIC (IC140)
through FL302 and FL303. BBIC performs QPSK demodulation and ADPCM decoding to convert the signal into the voice
signal, then it is output to the speaker.
relay (Q110) is turned ON and amplified at the amplifiers Q103 and Q116, then led to BBIC (IC101).BBIC generates I and Q
signals by performing ADPCM conversion and QPSK modulation. These I and Q signals are mixed with pseudo random noise
code (PN code) to spread the spectrum, then TXI and TXQ signals are output. RFIC (IC301) outputs TXI and TXQ signals as
RF signal. The RF signal is passed through the filter (FL305) and amplified by 3 power amplifiers of Q303, Q302 and Q301,
then led to antenna switch (D301) and filter (FL304) to be transmitted from the antenna. As for the handset, RF signal from the
antenna is input to RFIC passing through filters of FL304 and FL301 to perform the de-spread, then input to BBIC (IC140)
through FL302 and FL303. BBIC performs QPSK demodulation and ADPCM decoding to convert the signal into the voice
signal, then it is output to the speaker.
Transmission
The voice signal input from the microphone is amplified at the amplifier (Q105) and led to BBIC (IC140). As well as the
reception, BBIC (IC140) performs ADPCM conversion, QPSK modulation and spectrum spread to output TXI and TXQ signals.
They are converted into the RF signal by RFIC (IC301). Passing through the filter (FL305), power amplifiers (Q303, Q302 and
Q301), antenna switch (D301) and filter (FL304), it is transmitted from the antenna. As for the base unit, RF signal from the
antenna is input to RFIC (IC301) passing through filters of FL304 and FL301 to perform the de-spread, then input to BBIC
(IC140) through FL302 and FL303. BBIC performs QPSK demodulation and ADPCM decoding to convert the signal into the
voice signal. The voice signal is amplified at the TX amplifier (Q115 and Q107), then output to the TEL line (CN102) through
the relay (Q110) and bridge (D118).
reception, BBIC (IC140) performs ADPCM conversion, QPSK modulation and spectrum spread to output TXI and TXQ signals.
They are converted into the RF signal by RFIC (IC301). Passing through the filter (FL305), power amplifiers (Q303, Q302 and
Q301), antenna switch (D301) and filter (FL304), it is transmitted from the antenna. As for the base unit, RF signal from the
antenna is input to RFIC (IC301) passing through filters of FL304 and FL301 to perform the de-spread, then input to BBIC
(IC140) through FL302 and FL303. BBIC performs QPSK demodulation and ADPCM decoding to convert the signal into the
voice signal. The voice signal is amplified at the TX amplifier (Q115 and Q107), then output to the TEL line (CN102) through
the relay (Q110) and bridge (D118).
Fig. 9-1 BASE UNIT
Fig. 9-2 HANDSET
14
KX-TC1800B
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