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This thesis presents the design, implementation, and
measurement of a L-band downconverter, VHF circuits, and related
RFICs for a digital audio broadcasting (DAB) receiver RF front-
end. A dual frequency conversion strategy is employed in this
RF front-end (1.452-1.492 GHz). The 1st LO is at 1.28 GHz and
the 1st IF is from 172 MHz to 212 MHz. The 2nd LO (for VHF
tuner) is from 215 MHz to 255 MHz and the 2nd IF is 43 MHz. The
L-band downconverter includes a single-stage low noise amplifier
(9.7 dB gain and 1.65 noise figure) , a voltage control
amplifier (50 dB turning range and 17 dB gain), a phase-locked
oscillator (6 dBm output power and -95 dBc/Hz@ 10 kHz), and an
active mixer (8 dB noise figure, 15 dB conversion gain and 15
dBm OIP3 ). The L-band downconverter with 43 MHz voltage
control amplifier (70 dB turning range and 38 dB gain) are
design and combined with suitable IF ICs and filters to form a
DAB receiver RF front-end (not including the VHF frequency
synthesizer). The DAB receiver RF front-end has 65 dB
conversion gain, 5 dB noise figure and 19 dBm OIP3. In digital
modulation measurements, a 384 kbps p/4-DQPSK signal is applied
to the DAB receiver RF front-end and measured by a HP 89410A
vector signal analyzer. The measured error vector magnitude
(EVM) is 1.3% and adjacent channel power (ACP) is 43 dBc. For
1.6 Mbps 16-QAM digital modulation, the error vector magnitude
is 2.6% and adjacent channel power is 38 dBc. This thesis
also presents the design and measured performance of a DAB L-
band LNA and mixer RFICs. For RFIC design, the equivalent
circuits of RFIC/MMIC components are developed by using the HP-
MDS RF/Microwave circuit CAD tool. The two-stage LNA RFIC has
18.2 dB gain, 3.2 dB noise figure and 18.4 dBm OIP3. The dual-
gate mixer RFIC has 2 dB conversion loss, 20 dB LO-RF isolation
and 9.4 dB OIP3.
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