Modular High Power Ku-Band Polarisation Devices for Space Applications Philipp Kohl 28-29.04.2015
Outline Motivation Mission Scenarios Investigated Polarisation Devices Polarisation Device Principle Requirements Results of the Investigated Polarisation Devices Conclusion 2
Motivation Increased available power on telecommunication satellites More than 2kW per polarisation A single satellite needs to cover an increased number of frequency bands Life Time of 15 years Operable temperature range from -155 C to 170 C Flexibility with respect to frequency and polarisation allocation Increasing demand on circularly polarised antenna systems Due to increasing demand for communication capacity orthogonal dual polarised feed chains are required Combined Tx/Rx Bandwidth 10 12 14 16 18 20 Frequency [GHz] Need for modular high power Ku-Band polarisation devices 3
Mission Scenarios Three mission scenarios were derived from customer requests, for which such polarisation devices are required Scenario 1 FSS Tx/Rx Frequency [GHz] Tx: 10.70-12.75 Rx: 12.75-14.80 Scenario 2 FSS/BSS Tx/Rx Tx: 10.70-12.75 Rx1: 12.75-14.80 Rx2: 17.20-18.40 Scenario 3 BSS Tx/Rx Tx: 10.70-12.75 Rx: 17.20-18.40 Polarisation Linear Linear Circular Power Handling 2 x 28 x 140 W 2 x 24 x 110 W 2 x 16 x 110 W 4
Polariser Principle: Scenario 1 (FSS Tx/Rx Polarisation Device) The polarisation device FSS Tx/Rx is used for a linearly polarised mission scenario. Principle Turnstile based OMJ was used Equal excitation of two linearly polarised orthogonal modes Diplexer is used for frequency separation (Tx, Rx) Schematic: Scenario 1 Requirements Return Loss (> 21 db) Port-2-Port Isolation (> 45 db) Ohmic Loss (< 0.10 db) 5
Investigated Scenario 1: FSS Tx/Rx Polarisation Device All Simulations were done using CST Microwave and Design Studio 2014 CST-Model T-Solver was mainly used F-Solver for resonant structures Convergence was analysed For the System Analysis CST Design Studio was used Accurate and fast results 6
Magnitude [db] Modular High Power Ku-Band Polarisation Devices for Space Applications Investigated Scenario 1: FSS Tx/Rx Polarisation Device Archived very good RF-Results Measured results agree very well with the predicted CSTsimulation results 0-10 MHPKU FSS Tx/Rx - System Analysis Amplitude Return Loss narrow wide Operating Band -20-30 -40-50 10.5 11 11.5 12 12.5 13 13.5 14 14.5 15 Frequency [GHz] 7
Polariser Principle: Scenario 2 (FSS/BSS Tx/Rx Polarisation Device) The polarisation device FSS BSS Tx/Rx is used for a linearly polarised mission scenario. Principle Turnstile based OMJ was used Equal excitation of two linearly polarised orthogonal modes Quadruplexer is used for frequency separation (FSS Tx, FSS Rx, BSS Tx, BSS Rx) Schematic: Scenario 2 Requirements Return Loss (> 21 db) Port-2-Port Isolation (> 45 db) Ohmic Loss (< 0.15 db) 8
Investigated Scenario 2: FSS/BSS Tx/Rx Polarisation Device All Simulations were done using CST Microwave and Design Studio 2014 CST-Model T-Solver was mainly used F-Solver for resonant structures Convergence was analysed For the System Analysis CST Design Studio was used Accurate and fast results 9
Magnitude [db] Modular High Power Ku-Band Polarisation Devices for Space Applications Investigated Scenario 2: FSS/BSS Tx/Rx Polarisation Device Archived very good RF-Results Measured results agree very well with the predicted CSTsimulation results 0-10 MHPKU FSS/BSS Tx/Rx - System Analysis Amplitude Return Loss narrow wide Operating Band -20-30 -40-50 10.5 11.5 12.5 13.5 14.5 15.5 16.5 17.5 18.5 Frequency [GHz] 10
Polariser Principle The polarisation device BSS Tx/Rx is used for a circularly polarised mission scenario. Principle Coaxial Diplexing OMJ was used for frequency separation Equal excitation of two circularly polarised orthogonal modes Diplexer is used for seperating FSS Tx and BSS Tx Schematic: Scenario 3 Requirements Return Loss (> 21 db) Port-2-Port Isolation (> 19 db) Ohmic Loss (< 0.25 db) 11
Investigated Scenario 3: BSS Tx/Rx Polarisation Device All Simulations were done using CST Microwave and Design Studio 2014 T-Solver was mainly used F-Solver for resonant structures Convergence was analysed For the System Analysis CST Design Studio was used Accurate and fast results 12
Magnitude [db] Modular High Power Ku-Band Polarisation Devices for Space Applications Investigated Scenario 3: BSS Tx/Rx Polarisation Device Hardware currently in manufacturing process Archived very good RF-Results 0-10 MHPKU DB coax. Diplexer - 1350 Amplitude Return Loss and Isolation Return Loss Isolation Operating Band -20-30 -40-50 10.5 11 11.5 12 12.5 13 Frequency [GHz] 13
Magnitude [db] Modular High Power Ku-Band Polarisation Devices for Space Applications Investigated Scenario 3: BSS Tx/Rx Polarisation Device Hardware currently in manufacturing process Archived very good RF-Results MHPKU DB coax. Diplexer - Septum Polariser 1355-1 Amplitude Return Loss and Isolation 0-10 Return Loss Isolation Operating Band -20-30 -40-50 17.2 17.7 18.2 18.7 Frequency [GHz] 14
Conclusion Three different mission scenarios are derived from customer request Three modular polarisation devices were investigated to fulfill the requirements Very good RF-results were archived Simulated RF-Results agree very well with the measured RF-Results 15
Modular High Power Ku-Band Polarisation Devices for Space Applications Philipp Kohl 28-29.04.2015