System Specifications Lab Tests KFPA CDR Jan 30-31, 2009 System Specs KFPA CDR Jan 30-31 2009
General Requirements Lab Results Frequency Range: 18-26.5 GHz; goal 17-27.5 GHz with degraded performance. Instantaneous Bandwidth: 1.8 GHz minimum. Noise Temperature: 36 K maximum 18-26.5 GHz; 25K maximum over 75% Polarization Axial Ratio: 1 dB maximum Polarization Isolation: 25 dB minimum (within a pixel). Pixel-Pixel Isolation: 30 dB minimum Output Flatness: 3dB p-p maximum Linearity: 30 dB below 1dB point at 300K System Specs KFPA CDR Jan 30-31 2009
System Specs KFPA CDR Jan 30-31 2009 Frequency Range System gain falls off rapidly outside 18-26.5 GHz and noise temp increases, but might be usable just outside for some applications. System Specs KFPA CDR Jan 30-31 2009
System Specs KFPA CDR Jan 30-31 2009 Frequency Range Of the cooled components, the OMT limits the upper frequency. System Specs KFPA CDR Jan 30-31 2009
System Specs KFPA CDR Jan 30-31 2009 Noise Temperature Receiver noise is less than the current K-band rx, and Tcal varies more smoothly. System Specs KFPA CDR Jan 30-31 2009
Axial Ratio Measurements Measured axial ratio is well less than the 1dB spec. Freq (GHz) LCP (dB) RCP (dB) 19 0.44 0.20 22 0.42 0.62 24 0.38 0.29 25 0.34 0.28 26 0.70 0.54 System Specs KFPA CDR Jan 30-31 2009
System Specs KFPA CDR Jan 30-31 2009 Isolation Polarization Isolation Prototype IDM1 has low isolation at some frequencies that will be corrected. OMT polarization isolation >35 dB Pixel-Pixel Isolation not yet measured. Have checked thermal gaps and are OK. System Specs KFPA CDR Jan 30-31 2009
System Specs KFPA CDR Jan 30-31 2009 Gain Flatness Measured thru dewar and IDM-2. Ripple originates inside the dewar, mismatch error between LNA output and waveguide window thru ~40cm interconnecting wg. System Specs KFPA CDR Jan 30-31 2009
System Specs KFPA CDR Jan 30-31 2009 Linearity IDM variable attenuators before final IF amps allow adjustments. With min atten, Tsys=100K, we’re ~25dB below P1db. System Specs KFPA CDR Jan 30-31 2009