C903
1228-1147 rev. 1
FUNCTIONAL OVERVIEW
FU
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FU
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C
TI
O
N
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L O
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Technical Description
FUNCTIONAL OVERVIEW
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FUNCTIONAL OVERVIEW
FU
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EGSM 900:
RX Frequency Range: 925,2 MHZ – 934,8 MHZ
Channel Range RX: 975 – 1023
DCS 1800:
RX Frequency Range: 1805,2 MHZ – 1879,8 MHZ
Channel Range RX: 512 – 885
PCS 1900:
RX Frequency Range: 1930,2 MHZ – 1989,8 MHZ
Channel Range RX: 512 - 810
WCDMA
Note!
WCDMA Network support depends on variant and market.
TX and RX Frequency and Channel Range
Band I:
Channel Range TX: 9612 - 9888
TX Frequency Range: 1920 – 1980 MHz
Channel Range RX: 10562 - 10838
RX Frequency Range: 2110 – 2170 MHz
Band II:
Channel Range TX: 9262 - 9538
TX Frequency Range: 1850 – 1910 MHz
Channel Range RX: 9662 - 9938
RX Frequency Range: 1930 – 1990 MHz
Band IV:
Channel Range TX: 1312 - 1513
TX Frequency Range: 1710 – 1755 MHz
Channel Range RX: 1537 – 1738
RX Frequency Range: 2110 – 2155 MHz
Band V:
Channel Range TX: 4132 – 4233
TX Frequency Range: 824 – 849 MHz
Channel Range RX: 4357 – 4458
RX Frequency Range: 869 – 894 MHz
Band VIII
Channel Range TX: 2712 – 2863
TX Frequency Range: 880 – 915 MHz
Channel Range RX: 2937 – 3088
RX Frequency Range: 925 – 960 MHz
Bluetooth and FM Radio
The Blt/FM Radio circuit combines Bluetooth and FM tuner functionality into one.
Bluetooth
The Bluetooth implementation is compliant with Bluetooth specification 2.1 + EDR.
The Bluetooth
TM
transceiver has frequency channels with 1 MHz separation from 2402 to
2480 MHz. The same band is used for both transmission and reception. This gives 79
frequency channels.
Receiver
The Bluetooth section implements a low-IF receiver for Bluetooth modulated input signals.
The radio signal is taken from a balanced RF input and amplified by an LNA. The mixers
are driven by two quadrature LO signals, which are locally generated from a VCO signal
running at twice the frequency. The I and Q mixer output signals are band pass filtered by
a poly-phase filter for channel filtering and image rejection. The output of the band pass
filter is amplified by a VGA to the optimal input range for the A/D converter. Further
channel filtering is done in the digital part. The digital part demodulates the GFSK,
Ⱥ
/4-
DQPSK or 8-DPSK coded bit stream by evaluating the phase information. RSSI data is
extracted. Overall automatic gain amplification in the receive path is controlled digitally.
The RC time constants for the analog filters are automatically calibrated on chip.
Transmitter
The transmitter uses the serial transmit data from the Bluetooth Controller. The
transmitter modulator converts this data into GFSK,
Ⱥ
/4-DQPSK or 8-DPSK modulated I
and Q digital signals for respectively 1, 2 and 3 Mbps transmission speed. These signals
are then converted to analog signals that are low pass filtered before up-conversion. The
carrier frequency drift is limited by a closed loop PLL.
FM Radio
FM Receiver
The receiver uses a digital low-IF architecture. The receive (RX) section integrates a low
noise amplifier (LNA) supporting the worldwide FM broadcast band (76 to 108 MHz). An
automatic gain control (AGC) circuit controls the gain of the LNA to optimize sensitivity
and rejection of strong interferers. An image-reject mixer down converts the RF signal to
low-IF. The quadrature mixer output is amplified, filtered and digitized with high resolution
analog-to-digital converters (ADCs). This advanced architecture allows the use of digital
signal processing (DSP) to perform channel selection, FM demodulation and stereo audio
processing.
Tuning
The receiver uses frequency synthesizer technology including a completely integrated VCO.
The frequency synthesizer generates the quadrature local oscillator signal used to
downconvert the RF input to a low intermediate frequency. The VCO frequency is locked to
the reference clock and adjusted with an automatic frequency control (AFC) servo loop
during reception. The tuning frequency is defined as: Freq (MHz) = Spacing (kHz) ×
C Bottom of Band (MHz)
SEMC Troubleshooting Manual
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