Ascent Ground and Satellite Demonstration By Ray Roberge, WA1CYB & Howie DeFelice, AB2S WA1CYB s1
Big Picture Goals Place more capable satellites into higher orbits Utilize software defined radios A programmable transponder that supports multiple linear and non-linear (FM) conversations simultaneously Digital modulation support Multi-users SHARING the Output Power Downlink assumed to be in X band (10.45 GHz), or greater Real time Doppler compensation WA1CYB s2
Current Focus Goals C-Band Uplink, X-Band Downlink (five and dime) Provide Frequency/Time Locking Capability for the Ground Station Utilize SDR technology to maximize flexibility to Experiment and Modify Operation Optimize Satellite architecture to minimize Ground Station costs Provide for maximum Power Weighting @Output for the downlink to prevent satellite capture UHF/VHF/L-Band/S-Band/HF optional Uplinks Provide a Digital Downlink of Satellite Data Provide a Digital Downlink of ID, Time stamp, Location (ala GPS/Grid Square) and uploaded TLE Provide for a DVB-S2 Input & Output when available Build in Redundant paths where feasible Provide multiple Digital Downlink paths Provide multiple Voice Downlink paths with different modulation types Provide a Multi-channel In- Single Channel out for contact Initiation and/or emergency channel Provide a controlled Ham Band Scanner Survey Downlink Capability WA1CYB s3
General Approach Build and Demonstrate an example Ground and Satellite system that gives the user a sense of what a modern satellite system might look and feel like Concentrate on the system, not the implementation Talk to me about GNU Radio flow graphs at the demonstration area Incorporate the latest technology that is available and cost effective Use hardware and software that is identical or mimics planned future systems Make the communication architecture programmable to facilitate experimentation and optimization Use COTS SDR(s) likely to be used to facilitate early launch opportunities WA1CYB s4
Demonstration Approach Satellite Demo: Use available ETTUS SDR (N210) instead of the E310 or B205 that is desired. Use a laptop running GNU Radio software with UBUNTU Linux GNU Radio SW is loaded internally in the E310 version, but we needed a display Use a cheap RTL-SDR as the second satellite receiver Ground Station Demo: Use available ETTUS SDR (N210) instead of the E310 or B205 that is desired. Use a laptop running GNU Radio software with UBUNTU Linux GNU Radio SW is loaded internally in the E310 version, but we needed a display Use a cheap RTL-SDR as the local receiver in place of a microphone input WA1CYB s5
Ascent Demonstration- AMSAT Symposium 0.44, 1.26, 2.4, 3.4 GHz bands ~5.6 GHz 0.145, 0.44, 1.26 GHz bands Uplink-1 Receiver Uplink-2 Receiver What should be inside the SDR Satellite Computer Receives Ground Station C-band Demodulates Uplink signals, both Digital and Analog Cleans them up and weights them for retransmission Adds frequency/time lock signal Adds any cmd downlink and msg Transmits to Ground (Downlink) Downlink Transmitter ~10.3 GHz 0.4 to 4.4 GHz 0.145, 0.44, 1.26 GHz bands Uplink Transmitter Local Receiver Ground Station Computer Receives Local Transmissions Converts Audio for uplink Transmits Audio(s) to Satellite Receives Sat Sim via X-band Processes received Data stream Locks Frequency Selects output channel(s) Downlink Receiver LNB ~0.6 GHz Local Receiver added & Tuned to VHF/UHF For this Demonstration Only WA1CYB s6
3U Satellite Demo Connection Diagram (Commo) LPA 0.4 to 4.4 GHz Satellite Simulator Computer 0.4 to 4.4 GHz SMA Patch 10.0 10.4 GHz Vert. SMA Atten 6 m to 23 cm ETTUS SDR (Rcvr) SMA to MCX 5V Wart RTL-SDR (Rcvr) Boot to UBUNTU LINUX Ascent Folder Demo on Desktop Runs GNU radio /GRC Charger ETTUS SDR (XMTR) 5V Wart Pwr Strip SMA SMA SMA ~ Up-Converter Oscillator 6 GHz AC Power Avenger LNB 10.0 10.4 GHz LPA LO = 9.75 GHz LNB 5.65 5.67 GHz Vert. Local Receiver SMA Atten 6 m to 23 cm ETTUS SDR (XMTR) SMA to MCX RTL-SDR (Rcvr) Ground Node Computer Boot to UBUNTU LINUX Ascent Folder SDR-ConsoleV3 for testing Demo on Desktop Runs GNU radio /GRC 38+ Frequency Channels 250 650 MHz RTL-SDR (Rcvr) SMA to MCX SMA Cable 18V Wart SMA Atten DC Block Wire V Type-F to SMA Type-F Dual DC Power Inserter V Type-F H H Type-F Cable Speaker 5V Wart Charger Pwr Strip AC Power WA1CYB s7
LSB USB PSK31 PSK31 BPSK USB NBFM Tone Locking Carrier Time Example Downlink Frequency Band Plan Arbitrary Peak Weighting WB-Digital PSK31 CW Location Pulse(s) -83-35 -37-32 -30-25 -19-9 -33-31 0-128kHz 1. Tone Locking Carrier: Enables Ground Lock of Spectrum when Doppler is present 2. NBFM: Voice Channel(s) Translated from a Low Band 3. USB: Combined Multi-channel In Initiate contact and/or emergency channel down 4. BPSK: ID, Telemetry and data stream from satellite 5. CW: CW Bandwidth(s) Translated from a Low Band 6. PSK31-3: Satellite broadcast of ID, Time stamp, Location (ala GPS) and TLE 7. PSK31-2: Chat Channel #2 8. PSK31-1: Chat Channel #1 9. USB: Channel #3 10. LSB : Channel #4 11. Wide Band Digital: Channel #5 12. Location Pulse(s): Enables Precise Ranging/Location 128kHz WA1CYB s8
As Seen at Avenger LNB Output (Noise in at 5.5 GHz, Few channels enabled, Sat Out at 10.45 GHz) WA1CYB s9
Example Channel Breakdowns Frequency Translate And Filter AGC Squelch Weighted Linear Channel Frequency Translate And Filter Wgt Weighted FM Channel Frequency Translate And Filter AGC CTCSS Squelch NBFM Rcvr NBFM Xmit Filter Frequency Translate And Filter Wgt Frequency Translate And Filter AGC Squelch Weighted PSK-31 Linear Channel DVB-S2 FDM/TDM Channel Frequency Translate And Filter Wgt Frequency Translate And Filter AGC Squelch Frequency Channelizer Demod / Mod Time Multiplexer Filter Frequency Translate And Filter Wgt Frequency Translate And Filter AGC Squelch Weighted 9600 BPSK 9600 BPSK Demod 9600 BPSK Mod Filter Frequency Translate And Filter Wgt WA1CYB s10
Demo Ground Station 0.4 to 4.4 GHz Uplink SDR-Xmtr Chat Display Frequency Display Freq. Division Combiner Voce and Data Recorded Message s De modulation FDM Channel Select Chat Channel Select Time Lock Speaker 10->10.5 GHz Frequency Lock LNB 9.75 GHz LO UHF/VHF/L-Band SDR-Rcvr.2 Local Receiver Tuned to a ham band RTL: freq. <1300 MHz AGC Squelch NBFM Rcvr NBFM Xmit Filter SDR-Rcvr.1 0.25->1.0 GHz WA1CYB s11
Amateur Radio Science Experiment Possibilities 2 nd receiver can be tasked to do other functions Conduct an Amateur Frequency Survey (multi-bands) Examine propagation via WSPR and WJT modes Upper atmosphere scattering Urban noise sources versus frequency etc. Multiple frequency inputs on different bands with common output band channel (Cross band input) for emergency use. Hoot and Holler Conference call Shared Aperture Antenna Steering Automatic logging of satellite users/peak signal level /vs satellite location Very weak satellite transmitter power beacon experiments (no power amplifier, straight SDR power) Even more satellite input frequency receivers (1 chip for each 2 frequency bands) Harmonic beacons for frequencies above x-band endless possibilities! ~5 Minutes to Transfer 1 Complete Set of Measurements Using 1 Output Channel WA1CYB s12
Go See the Demonstration! The Following slides show in a series of 5 test builds what the satellite could do If you want to build your own system, start with the simplest linear satellite (sat_test_1) Git-hub site has all the sat_test flow diagrams Helpful Notes contained in the flow graphs Sat-test_1.grc Linear repeater +/- 128 khz w/ single agc and squelch CW tone at the output center frequency, f 0out ID (cw) at f 0out 30.5 khz Pseudo Doppler available (As if in LEO or higher orbit) Sat-test_2.grc Sat_test_1.grc capability plus Added nbfm channel at receive center frequency, f 0in Added nbfm output at f 0out -9 khz Squelch shown set low, Noise in nbfm Channel only Audio enabled for demo purposes Sat-test_3.grc Sat_test_2.grc capability plus Shifted 128kHz of input to f 0in -62.5 khz Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise shifted up 12.5 khz and attenuated 100 db Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f 0out -125 khz to f 0out -62.5 khz Added 8 input channels (7 useable) linear channels (7.81 khz bw) Lower edge if the bank at f 0out -13kHz, upper edge at f 0out -59 khz Note that cw ID is also placed in the lower part of the 3 rd filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1 st filter from nbfm Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4 th 7.81 khz linear channel at ~f 0out -40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f 0out -125 khz Maxes out current external computer resource used for development https://github.com/wa1cyb/satellite_ground_emulator/tree/master/ascent/concept%20demo%20system WA1CYB s13
sat_test_1_0.png Sat-test_1.grc Linear repeater +/- 128 khz w/ single agc and squelch CW tone at the output center frequency, f 0out ID (cw) at f 0out 30.5 khz Pseudo Doppler available (As if in LEO or higher orbit) Pseudo Doppler TAB CW ID CD Tone WA1CYB s14
sat_test_1_1.png Sat-test_1.grc Linear repeater +/- 128 khz w/ single agc and squelch CW tone at the output center frequency, f 0out ID (cw) at f 0out 30.5 khz Pseudo Doppler available (As if in LEO or higher orbit) Pseudo Doppler set to LEO Equivalent Doppler Simulation for both Input and Output WA1CYB s15
sat_test_2_0.png Sat-test_2.grc Sat_test_1.grc capability plus Added nbfm channel at receive center frequency, f0in Added nbfm output at f0out-9 khz Squelch shown set low, Noise in nbfm Channel only Audio enabled for demo purposes nbfm Carrier WA1CYB s16
sat_test_2_1.png Sat-test_2.grc Sat_test_1.grc capability plus Added nbfm channel at receive center frequency, f0in Added nbfm output at f0out-9 khz Squelch shown set low, Noise in nbfm Channel only Audio enabled for demo purposes Pseudo Doppler set to LEO CW tone, cw ID and nbfm shifted w/ Doppler WA1CYB s17
sat_test_2_2.png Sat-test_2.grc Sat_test_1.grc capability plus Added nbfm channel at receive center frequency, f0in Added nbfm output at f0out-9 khz Squelch shown set low, Noise in nbfm Channel only Audio enabled for demo purposes nbfm Modulation WA1CYB s18
sat_test_3_0.png Sat-test_3.grc Sat_test_2.grc capability plus Shifted 128kHz of input to f0in-62.5 khz Squelch set to -58 db WA1CYB s19
sat_test_3_1.png Sat-test_3.grc Sat_test_2.grc capability plus Shifted 128kHz of input to f0in-62.5 khz Squelch set to -64 db Max Gain Upper Noise apparent WA1CYB s20
sat_test_3_2.png Sat-test_3.grc Sat_test_2.grc capability plus Shifted 128kHz of input to f0in-62.5 khz Squelch set to -64 db Gain reduced 3 db (.707 voltage) Upper Noise < squelch WA1CYB s21
sat_test_4_0.png Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise shifted up 12.5 khz and attenuated 100 db Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f0out-125 khz to f0out-62.5 khz Added 8 input channels (7 useable) linear channels (7.81 khz bw) Upper edge if the bank at f0out-13khz, lower edge at f0out-59 khz Note that cw ID is also placed in the lower part of the 3rd filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1st filter from nbfm WA1CYB s22
sat_test_4_2.png Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise shifted up 12.5 khz and attenuated 100 db Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f0out-125 khz to f0out-62.5 khz Added 8 input channels (7 useable) linear channels (7.81 khz bw) Upper edge if the bank at f0out-13khz, lower edge at f0out-59 khz Note that cw ID is also placed in the lower part of the 3rd filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1st filter from nbfm Sat Receiver #2 Signal received Spectrum shifted to this output channel WA1CYB s23
sat_test_4_3.png Zoomed in with greater resolution Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise shifted up 12.5 khz and attenuated 100 db Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f0out-125 khz to f0out-62.5 khz Added 8 input channels (7 useable) linear channels (7.81 khz bw) Upper edge if the bank at f0out-13khz, lower edge at f0out-59 khz Note that cw ID is also placed in the lower part of the 3rd filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1st filter from nbfm Spectrum shifted to this output channel WA1CYB s24
sat_test_4_4.png Pseudo Doppler set to LEO Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise shifted up 12.5 khz and attenuated 100 db Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f0out-125 khz to f0out-62.5 khz Added 8 input channels (7 useable) linear channels (7.81 khz bw) Upper edge if the bank at f0out-13khz, lower edge at f0out-59 khz Note that cw ID is also placed in the lower part of the 3rd filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1st filter from nbfm Expect +/- 250 khz in 600 seconds, Demo scaled to 30 seconds WA1CYB s25
sat_test_4_6.png Built in Test equipment Stack used. Wide Band Noise Applied to input Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise shifted up 12.5 khz and attenuated 100 db Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f0out-125 khz to Shows f0out-62.5 the khz six 7.8 khz Added 8 input channels (7 useable) (7.81 khz bw) linear channels. One with Upper edge if the bank at f0out-13khz, lower edge at f0out-59 khz Note that cw ID is also placed in the lower the part cw of the ID 3rd added filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1st filter from nbfm Input Attenuation set to -20 db, Squelch to -28 db (so no nbfm) WA1CYB s26
sat_test_4_7.png Sat-test_4_r3.grc Sat_test_3.grc capability plus 250 khz noise Upper shifted up linear 12.5 khz Channel and attenuated Bank 100 now db visible Added 32 (30 useable) linear channels (1.95 khz bw) Output 30 channels at f0out-125 khz to f0out-62.5 khz Added 8 input channels (7 useable) linear channels (7.81 khz bw) Upper edge if the bank at f0out-13khz, lower edge at f0out-59 khz Note that cw ID is also placed in the lower part of the 3rd filter from nbfm Second receiver (SR2) enabled Linear output of SR2 placed in the 1st filter from nbfm Input Attenuation set to -20 db, Squelch down to -51 db WA1CYB s27
sat_test_5_0.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Shows three psk31 channels sharing one 7.8 khz channel Upper psk31 channel sharing one 1.95 khz linear channel WA1CYB s28
sat_test_5_1.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Upper psk31 channel sharing one 1.95 khz linear channel WA1CYB s29 db
sat_test_5_2.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Shows three psk31 channels sharing one 7.8 khz channel - Better resolution - Upper linear Channel Bank not visible, Not breaking squelch WA1CYB s30
PSK31(s) CW ID sat_test_5_3.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Upper linear Channel Bank not visible, Not breaking squelch WA1CYB s31
sat_test_5_4.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Upper psk31 channel sharing one 1.95 khz linear channel, zoomed in WA1CYB s32
sat_test_5_5.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Squelch at -46 db Upper linear channels noise over threshold PSK31 Visible PSK31 Not Visible PSK31 Visible WA1CYB s33
sat_test_5_6.png Sat-test_5.grc Sat_test_4_r3.grc capability plus Adjusted nbfm bw on receive Added three psk31 transmit streams, 1kHz apart, each with ID text Three placed in 4th 7.81 khz linear channel at ~f0out-40 khz Placed another psk31 stream on a reduced output upper stream Output frequency just under f0out-125 khz Maxes out current external computer resource used for development! Squelch at -40 db Upper linear channels noise under threshold PSK31 Visible PSK31 Visible PSK31 Visible WA1CYB s34
Go See the Demonstration! WA1CYB s35
Operational Procedure- rev A Operation of the Ground Station 1 Warm up receiver and LNB 2 Run Frequency Calibration using ATSC pilots (Resulting error between 500 and 650MHz is less than 100 Hz 3 Turn GS receiver on SDR w/ LNB), input offset if needed 4 Turn GS C-band transmitter at known frequency and look for 2 nd Harmonic in GS receiver SDR w/ LNB) 5 Measure Offset error and save, This is the LNB error + transmitter error + corrected SDR receiver error (GS error). Restart if required 6 Wait for Satellite, monitor beacon frequency range 7 After CW/Range beacon is visible, Center manually on the display. This is the GS error+ Satellite error + Doppler + Satellite frequency error 8 Subtract the GS error in step 5 from the measured frequency in step 7. This is the Satellite error + Doppler + Satellite frequency error 9 Turn on the Satellite error + Doppler + Satellite frequency error lock circuit 10 All receiver channels should be locked to the satellite and track it within +/-250Khz (LEO X-band) 11 Transmit with selected offset (channel) on a unused channel 12 Verify receiver picks up transmitter on frequency translation to X-Band. 13 Antenna Rotation Control not demonstrated (this time) Operation of the Satellite Station 1 Warm up SDRs (Receiver and Transmitter) 2 Bypass command structure and turn on system manually 3 Enable CW/Range Beacon 4 Enable C-band receiver Band 5 Enable Transmitter System Operation Verification 1 Use HT to talk to ground station on Channel zero 2 Verify reception on Channel zero on the Ground Station at X-band WA1CYB s36