Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
Receiver
Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
Tuned Radio Frequency Receiver
limited gain that can be obtained before oscillation occurs need to tune several stages in parallel selectivity is poor because the pass-band of filters is fairly broad
3
Institut für Hochfrequenztechnik IHE und Elektronik
Institut für Hochfrequenztechnik IHE und Elektronik
Superheterodyne Receiver with Dual-Down Conversion
At microwave and millimeter wave frequencies it is often necessary to use two stages of down conversion to avoid problems due to LO stability (dual-down conversion system). The dual-conversion superheterodyne receiver employs two local oscillators and mixers to achieve downconversion to baseband with two IF frequencies. 5
Institut für Hochfrequenztechnik IHE und Elektronik
Transmitter
Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
High Power Transmitter Sideband Filter
Amp.
Frequency Synthesizer
AM Modulator
Power Amp.
COHO
Local Oscillator
7
Institut für Hochfrequenztechnik IHE und Elektronik
Communication Systems
Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
Direct Conversion Receiver
9
Institut für Hochfrequenztechnik IHE und Elektronik
Direct Conversion Receiver
Advantages: selectivity can be controlled with a simple low-pass baseband filter gain may be spread through the RF and baseband stages simpler and less costly than superheterodyne receivers since there is no IF amplifier, IF bandpass filter, or IF local oscillator no image frequency
Disadvantage: LO must have a very high degree of precision and stability
10
Institut für Hochfrequenztechnik IHE und Elektronik
Radar
Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
FM-CW -Radar (Range and Doppler) FM GENERATOR
Doppler
Range
fIF(t) MODULATOR
f0(t)+ fIF(t)
PA
Switched Freq. Counter
LO Average Freq. Counter Video Amps
fo
I ADC, Signal Processor, Display
fB±fD
I/Q Demod. Q
LNA
IFA
(f0+fIF)(t-t)+fD
fIF(t-t) +fD 12
Institut für Hochfrequenztechnik IHE und Elektronik
24GHz CW Doppler-Radar Coupler (3dB)
Tx-Antenna
PIN-Modulator Dielectric Resonator
Balanced Mixer 1 (6x /4)
Oscillator Transistor WilkinsonDevider
Rx-Antenne Coupler (3dB) for 2 Balanced Mixer
Rx LNA
5.5cm
Balanced Mixer 2 (6x/4)
DC Supply
7.8cm
Courtesy Tyco 13
Institut für Hochfrequenztechnik IHE und Elektronik
mm-Wave FM-CW Radar (Surface&Subsurface Sensing) Low frequency circuits Power divider
LPF VCO
High frequency circuits Harmonic mixer
Amp.
Circulator
Antenna Power divider Loop Filter
Divider
LNA
Amp.
Amp.
PD TCXO Amp.
2 X LPF
Amp. Synthesizer Quad. Demod.
I
Harmonic mixer
Q
Data acquistion
Computer
f in GHz: 29,72 - 37,7 resolution in mm: ± 1 14
Institut für Hochfrequenztechnik IHE und Elektronik
RFE System Example 76 GHz Distance Sensor
Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
Layout of the Radar Sensors and Test Structures Tx-antenne VCO
Tx-amp
Test structures
Power splitter Hybridcoupler LOamplifier DC-decoupling
power splitter
LNA
Rat-racemixer
Rx-antenne
1mm2 36
Institut für Hochfrequenztechnik IHE und Elektronik
RFE System Example iPhone Transceiver Architecture
Forschungszentrum Karlsruhe in der Helmholtz - Gemeinschaft
Universität Karlsruhe (TH) Research University•founded 1825
iPhone Transceiver-Open Wireless Architecture
US Patent 7522888 38
Institut für Hochfrequenztechnik IHE und Elektronik
