Polarimetric Solid State Radar Design for CASA Student Test Bed Alexandra Litchfield Objective To design a Dual Polarimetric Solid State Doppler Radar for the CASA student Test Bed. Possible Radar Localization @ Aguadilla, PR Possible Radar Localization @ Mayaguez, PR Why Solid Sate Definition: Solid State Devices and Systems are based entirely on semiconductor. There is no mechanical action on a solid state device but electromagnetic action takes place. Current is confined to solid elements. Advantages: Does not need a high voltage modulator. Use less power (kW from Magnetron are eliminated) Coherent radars can be made. Pulse Compression can be used. Radar Requirements Radar Freq: 9.5-9.6 GHz (X Band) Peak Transmitter Power: 25W Minimum Detectable Signal Power: -100dBm Antenna Gain: 12dB Horizontal Antenna Beam Width: 6 degrees Vertical Antenna Beam Width: 6 degrees Pulse Width: 30us Max Range: 6km Project Phases Radar Front End TR Module Transmit/Receive Module Circuit Design Component Layouts Build and Test Phase shifter Phase shifter circuit design Component Layouts Build and Test Master clock distribution Digital Signal Processing Antenna Implementation Integration TR Original Preliminary Design Transmit Path IF Directional Coupler PA Circ. Limiter Power Combiner S LNA Calibration Path IF Receiver Path OSC Preliminary Design for Radar Front End Power Combiner Cal S LNA PreA PA RF Tx Rx LO Ø Phase shifter Phase shifter Ø Divider / Combiner Tx Rx IF Phase Shifter Preliminary Design 90 Hybrid Variable Amp. 90 Hybrid ∑ ∑ I Q 90 Hybrid Ø Q I Vcc2 Design with Vector Modulator Phase Shifter Tx IF2 I Q IF2 RF Vector Mod Vcc1 Circ. LO2 IF2 20MHz I Limiter Noise Power Combiner Q Directional Coupler PA Rx LNA LO1 IF LO2 Vector Mod Vcc1 Vcc2 20MHz LO1 IF1 IF1 I Q One Polarization Channel LNA PA Limiter Receive Path Cal Path Power Combiner Transmit Path Directional Coupler Circ. Noise LO2 Vcc2 IF2 Vector Mod Phase shifter LO1 Vcc1 LO1 IF1 IF1 Components Mixer: Alters the carrier frequency of the signal. Oscillator: Controls the frequency used to sincronized the radar. Directional Coupler / Power Divider: Couples part of the transmision power in to the transmision line. Limiter: Circuit that allows to pass the unaffected received signal Low Noise Amplifier (LNA): Amplifies weak signals captured by the antenna. Circulator: Redirect signal that comes in an out from/to transmisor and receptor. Radar’s Dual Polarized Antenna Dual polarization Antenna Operating at 9.5GHz Array of Apertured Coupled Antennas Received Power Calculations G=16dB; Ganancia R=6km; Maximum Range C=3x10^8 m/s; velocity of light Pt=2W Power Transmitted by each channel. H=30usec; Pulse Width F= 9.5 GHz Lambda=c/f =.031579 K=dielectric factor (.93 for water) Z=10dBz; 10=10log(P), P=10 MDS = -100dBm N=2.66x10^9 G=39.81W Pr=1uW=-30dBm Component Layout Power Amplifier HMC48LP5 Low Noise Amplifier HMC564LC4 Component Layout Mixer HMC412M58G Future Work To construct and measure parameters for the TR Module and Phase Shifter. Digital Signal Processing. Antenna Implementation Integration Test and Measure Questions