Passive system and method to determine distortion in an RF satellite chain
View Patent ↗A system 10 that is used for analyzing a broadcast system includes a receiving device 60 that generates a baseband demodulated RF signal and digitizes the RF signal to form a digitized signal. A data capture module such as the IQ monitor board 90 is coupled to the receiving device 60 for acquiring samples of the digitized signal. A computer is communication with the data capture module. The computer processes the samples of the digitized signal to obtain a broadcast system response and an inverse broadcast system response. The display generates a display corresponding to the broadcast system response and the inverse system response.
1. A system analyzing a broadcast system comprising:
a receiving device generating a baseband demodulated RF signal and digitizing the RF signal to form a digitized signal;
a data capture module coupled to the receiving device for acquiring samples of the digitized signal;
a computer in communication with the data capture module, said computer processing the samples of the digitized signal to obtain a broadcast system response and an inverse broadcast system response; and
a display generating a display corresponding to the broadcast system response and an inverse broadcast system response.
2. A system as recited in claim 1 wherein the receiving device comprising a satellite signal receiver.
3. A system as recited in claim 1 wherein the receiving device comprises an integrated receiver decoder.
4. A system as recited in claim 1 wherein the receiving device comprises a forward error correction module, wherein the data capture module is in communication with the forward error correction module.
5. A system as recited in claim 4 wherein the data capture module determines uncorrected packets after the forward error correction.
6. A system as recited in claim 1 wherein the display displays a packet error count.
7. A system as recited in claim 1 wherein the inverse response comprises an equalization filter.
8. A system as recited in claim 7 wherein the equalization filter comprises a digital finite impulse response filter.
9. A system as recited in claim 1 wherein displaying comprises displaying the broadcast system response and inverse broadcast system response in a frequency domain.
10. A system as recited in claim 1 wherein displaying comprises displaying the broadcast system response and inverse broadcast system response in a time domain.
11. A system as recited in claim 1 wherein the broadcast system response and inverse broadcast system response comprises a broadcast system response for an RF chain and an inverse broadcast system response for the RF chain.
12. A system as recited in claim 11 wherein the RF chain comprises a satellite uplink, a satellite transponder and a satellite downlink.
13. A system as recited in claim 11 wherein the RF chain further comprises the receiving device.
14. A system as recited in claim 11 wherein the RF chain further includes a network operations center.
15. A system as recited in claim 11 wherein said data capture module does not perturb the RF chain.
16. A system as recited in claim 1 wherein the RF signal comprises a satellite digital television signal.
17. A system as recited in claim 1 wherein the computer processes the samples of the digitized signal to obtain a signal parameter.
18. A system as recited in claim 1 wherein the signal parameter comprises a bit error rate.
19. A system as recited in claim 1 wherein the signal parameter comprises a carrier plus noise to noise spectrum ratio at baseband.
20. A system as recited in claim 1 wherein the signal parameter comprises a power spectrum of said signal.
21. A system as recited in claim 1 wherein the signal parameter comprises signal noise in I-Q space.
22. A system as recited in claim 1 wherein the inverse response comprises an equalization filter.
23. A system as recited in claim 1 wherein the equalization filter comprises a digital finite impulse response filter.
24. A method of analyzing a broadcast system comprising:
generating a baseband demodulated RF signal;
digitizing the RF signal to form a digitized signal;
acquiring samples of the digitized signal to form digital signal samples; and
processing the digitized signal samples to obtain a broadcast system response and an inverse broadcast system response.
25. A method as recited in claim 24 further comprising displaying the broadcast system response and the inverse broadcast system response.
26. A method as recited in claim 24 wherein generating a baseband demodulated RF signal comprises generating the baseband demodulated RF signal at a receiving device.
27. A method as recited in claim 24 wherein the receiving device comprising a satellite signal receiver.
28. A method as recited in claim 24 wherein the receiving device comprises an integrated receiver decoder.
29. A method as recited in claim 24 wherein the step of acquiring samples of the digitized signal to form digital signal samples is performed in a data capture module.
30. A method as recited in claim 29 further comprising coupling the data capture module to a receiving device.
31. A method as recited in claim 24 further comprising forward error correcting the baseband demodulated RF signal.
32. A method as recited in claim 24 further comprising after forward error correcting, determining uncorrected packets after the forward error correction.
33. A system as recited in claim 32 wherein the displaying a packet error count in response to determining uncorrected packets.
34. A method as recited in claim 24 further comprising processing the samples of the digitized signal to obtain a signal parameter.