1. HIAPER Cloud Radar Transceiver Exciter Receiver Oscillators High-Powered Amplifier Calibration Exciter Receiver Oscillators High-Powered Amplifier Calibration

2. Overview Exciter Receiver Oscillators High-Powered Amplifier Calibration Exciter Receiver Oscillators High-Powered Amplifier Calibration

3. Exciter: Requirements 200 ns to 2 µs transmitted pulse (Phase A) –Requires 5 MHz linear-phase bandwidth Accommodate extension to a pulse compression waveform (Phase B system) such as an amplitude tapered linear FM or non-linear FM –Require arbitrary phase and amplitude control within generated pulse –Design for 20 MHz of linear-phase bandwidth in order to shape the spectrum of the transmitted pulse 200 ns to 2 µs transmitted pulse (Phase A) –Requires 5 MHz linear-phase bandwidth Accommodate extension to a pulse compression waveform (Phase B system) such as an amplitude tapered linear FM or non-linear FM –Require arbitrary phase and amplitude control within generated pulse –Design for 20 MHz of linear-phase bandwidth in order to shape the spectrum of the transmitted pulse

4. Exciter: Waveform Generator Baseband I and Q samples used to generate a Hilbert transform pair of signals centered at 125 MHz Images at 375 MHz (using 500 MS/s DAC) will be suppressed by 70 dB Allows for amplitude and phase control to shape the transmitted spectrum Baseband I and Q samples used to generate a Hilbert transform pair of signals centered at 125 MHz Images at 375 MHz (using 500 MS/s DAC) will be suppressed by 70 dB Allows for amplitude and phase control to shape the transmitted spectrum

5. Exciter: 1.3 GHz Up-Conversion Up-conversion to 1.3 GHz using a quadrature modulator Lower sideband is suppressed by > 20 dB Up-conversion to 1.3 GHz using a quadrature modulator Lower sideband is suppressed by > 20 dB

6. Exciter: Single Sideband Generation m(t) and m h (t) form a Hilbert transform pair centered in frequency at 125 MHz Output of the quadrature modulator is a single sideband signal (the lower sideband at 1050 MHz is suppressed) m(t) and m h (t) form a Hilbert transform pair centered in frequency at 125 MHz Output of the quadrature modulator is a single sideband signal (the lower sideband at 1050 MHz is suppressed) m(t) m h (t)

7. Exciter: 1.3 GHz Filtering Filter signal at 1.3 GHz to further suppress lower sideband by 40 dB (min.) Filter has a 20 MHz, linear phase passband Filter signal at 1.3 GHz to further suppress lower sideband by 40 dB (min.) Filter has a 20 MHz, linear phase passband

8. Exciter: 94 GHz Up-Conversion Up-convert 1.3 GHz signal to 94 GHz using a single sideband modulator Lower sideband signal at 91.4 GHz is suppressed by 20 dB Up-convert 1.3 GHz signal to 94 GHz using a single sideband modulator Lower sideband signal at 91.4 GHz is suppressed by 20 dB

9. Exciter: 94 GHz Filtering Filter 94 GHz signal to further suppress lower sideband at 91.4 GHz by 26 dB Transmitter will further suppress image due to limited bandwidth (~100 MHz) Filter 94 GHz signal to further suppress lower sideband at 91.4 GHz by 26 dB Transmitter will further suppress image due to limited bandwidth (~100 MHz)

10. Overview Exciter Receiver Oscillators High-Powered Amplifier Calibration Exciter Receiver Oscillators High-Powered Amplifier Calibration

11. Receiver: Requirements Receiver Requirements –5 MHz linear phase bandwidth (Phase A) Accommodate extension to a pulse compression waveform (Phase B system) –Desire 20 MHz of linear phase bandwidth –Non-polarimetric receiver (Phase A) that should be upgradeable to a fully- polarimetric receiver in Phase B Receiver Requirements –5 MHz linear phase bandwidth (Phase A) Accommodate extension to a pulse compression waveform (Phase B system) –Desire 20 MHz of linear phase bandwidth –Non-polarimetric receiver (Phase A) that should be upgradeable to a fully- polarimetric receiver in Phase B

12. Receiver: T/R Isolation Receiver must be protected from the reflected transmit signal from the antenna For an antenna with a 14 dB return loss (1.5:1 VSWR), an a peak incident power of 60.7 dBm at the antenna terminals, the signal at the input to the latching circulators is 45.4 dBm For a LNA max. input power of +20 dBm, T/R isolation required is 42 dB (2 latching circulators @ 25 dB each) Receiver must be protected from the reflected transmit signal from the antenna For an antenna with a 14 dB return loss (1.5:1 VSWR), an a peak incident power of 60.7 dBm at the antenna terminals, the signal at the input to the latching circulators is 45.4 dBm For a LNA max. input power of +20 dBm, T/R isolation required is 42 dB (2 latching circulators @ 25 dB each)

13. Receiver: 94 GHz Filtering Image rejection filter suppresses received signals at the image frequency by > 46 dB

14. Receiver: 94 GHz Down-Conversion Received signal is down- converted to 1.3 GHz If suppression of image at 91.4 GHz is not sufficient, then an image reject mixer will be used Received signal is down- converted to 1.3 GHz If suppression of image at 91.4 GHz is not sufficient, then an image reject mixer will be used

15. Receiver: 1.3 GHz Filtering Received signal is filtered which suppresses signals in lower sideband by > 40 dB (> 100 dB rejection)

16. Receiver: 1.3 GHz Down-Conversion Received signal is down- converted to 125 MHz The 5 MHz anti-aliasing filter will be changed for Phase B Received signal is down- converted to 125 MHz The 5 MHz anti-aliasing filter will be changed for Phase B

17. Receiver: Performance Receiver performance was calculated using commercially available components –Noise figure Receiver noise figure 9.35 dB (noise power in 5 MHz BW is −97.9 dBm) –Dynamic range Maximum input signal to the receiver is −22.4 dBm Dynamic range is −22.4 − (−97.9) = 75.5 dB 14 bit ADC required to capture receiver dynamic range –Intermodulation products will be analyzed during component selection Receiver performance was calculated using commercially available components –Noise figure Receiver noise figure 9.35 dB (noise power in 5 MHz BW is −97.9 dBm) –Dynamic range Maximum input signal to the receiver is −22.4 dBm Dynamic range is −22.4 − (−97.9) = 75.5 dB 14 bit ADC required to capture receiver dynamic range –Intermodulation products will be analyzed during component selection

18. Overview Exciter Receiver Oscillators High-Powered Amplifier Calibration Exciter Receiver Oscillators High-Powered Amplifier Calibration

19. Oscillators: Phase Noise Offset Frequency Phase Noise [dBc] 10 Hz−40 100 Hz−65 1 kHz−75 10 kHz−85 100 kHz−95 1 MHz−105 10 MHz−110 Phase noise analysis performed on W-band local oscillator using data in the table below to determine phase noise requirements Velocity variance due to phase noise for an echo at 10 km is 0.07 m/s Phase noise analysis performed on W-band local oscillator using data in the table below to determine phase noise requirements Velocity variance due to phase noise for an echo at 10 km is 0.07 m/s