1. Overview High-Powered Amplifier Exciter Receiver Oscillators
Calibration

2. HPA: Extended Interaction Klystron
EIK-based amplifier appears to be the best suited
Conduction cooled unit was developed for CloudSat
Mounted in a pressure vessel in the pod with modulator and RF front-end electronics
EIK Specifications
Center Frequency
94 GHz
Bandwidth (1 dB)
> 200 MHz
Peak Power
1.7 kW
Gain
50 dB
CloudSat Flight Model EIK

3. HPA: Extended Interaction Klystron

4. HPA: Extended Interaction Klystron

5. HPA: Modulator Requirements Options Looking for advice and comments
5 % duty cycle
Up to 20 kHz pulse repetition rate
Pulse lengths from 200 ns to 2 µs
Aircraft ready (vibration, attitude changes)
Options
Communications & Power Industries (CPI)
Expensive modulator
Reports of bad experiences
Pulse Systems
Cheap
Largely untested
Applied Systems Engineering (ASE)
Very expensive
Good engineering support
Looking for advice and comments

6. HPA: Waveguide Peak Power Considerations Average Power Considerations
WR-10 can handle around 8 % (1.34 kW at 94 GHz) of the waveguide theoretical peak power (Ciavolella, 1972)
Pressurize the front-end electronics waveguide with nitrogen
Average Power Considerations
Maximum rated average power of WR-10 is 18 W at 94 GHz
At 1 µs pulse length and a 10 kHz PRF, the average power out of the EIK is 17 W assuming no standing waves in the waveguide
May need to use heat-sinks and forced-air cooling to remove heat from the waveguide walls