Digitized reverse link monitor
A method of monitoring a broadband digitized reverse link system comprising monitoring at least one radio frequency down-convert path in at least one remote unit in the digitized reverse link system using an internal tone generating system, digitally verifying the health of at least one digitized communication link communicatively coupled to receive digital signals from a respective remote unit, and monitoring the health of a radio frequency up-convert path in a host unit communicatively coupled to receive the digital signals from the at least one digitized communication link in the digitized reverse link system using a wideband power detector in the host unit.
1. A method of monitoring a broadband digitized reverse link system, the method comprising:
internally monitoring at least one radio frequency down-convert path in at least one remote unit in the digitized reverse link system using an internal tone generating system in the at least one remote unit, wherein the internal tone generating system generates at least one single-frequency radio frequency tone and receives feedback of a combined signal that includes a broadband signal received at the remote unit summed with the generated single-frequency radio frequency tone; and
digitally verifying the health of at least one digitized communication link communicatively coupled to receive digital signals from a respective remote unit.
2. The method of claim 1 , wherein internally monitoring at least one radio frequency down-convert path comprises:
receiving the broadband radio frequency signal at the remote units;
generating the at least one single-frequency radio frequency tone having a known power level at a pilot tone generator in the remote units;
adding the at least one single-frequency tone to the received broadband signal to form the combined signal at the remote units;
digitizing the combined signal;
filtering a narrow band of the digitized combined signal at the remote unit to form a narrowband digitized signal;
detecting the narrowband digitized signal at the remote unit at a pilot tone receiver; and
determining the health of the radio frequency down-convert path based on the detecting.
3. The method of claim 2 , wherein digitally verifying the health of at least one digitized communication link comprises:
transmitting the unfiltered digitized combined signal through the digitized communication link; and
performing an error check of the unfiltered digitized combined signal transmitted on all of the at least one digitized communication links in the broadband digitized reverse link.
4. The method of claim 2 , wherein the generating is a periodic generating.
5. The method of claim 4 , wherein determining the health of the radio frequency down-convert path comprises:
determining a ratio of a power level of a current filtered narrowband signal to a power level of a last-measured filtered narrowband signal.
6. The method of claim 5 , wherein determining the health of the radio frequency down-convert path further comprises:
determining a ratio of the power level of the current filtered narrowband signal to a power level of a previously measured filtered narrowband signal.
7. The method of claim 4 , wherein determining the health of the radio frequency down-convert path comprises:
determining a ratio of the power level of a current filtered narrowband signal to a power level of a previously measured filtered narrowband signal.
8. The method of claim 4 , further comprising:
calibrating a power level of the at least one single-frequency tone, wherein the determining the health of the radio frequency down-convert path comprises,
determining a ratio of the power level of a current filtered narrowband signal to the power level of the calibrated single-frequency tone.
9. The method of claim 2 , wherein determining the health of the radio frequency down-convert path comprises:
comparing a level of the detected narrowband digitized signal to a threshold, wherein the radio frequency down-convert path is healthy when the level of the detected narrowband digitized signal is greater than the threshold.
10. The method of claim 1 , further comprising:
monitoring the health of a radio frequency up-convert path in a host unit communicatively coupled to receive the digital signals from the at least one digitized communication link in the digitized reverse link system using a wideband power detector in the host unit.
11. The method of claim 10 , wherein monitoring the health of a radio frequency up-convert path in the host unit comprises:
receiving the digitized combined signals from all of the at least one remote units at a summation circuit in the host unit;
summing the received digitized combined signals to form a digitized summed signal;
detecting the digitized summed signal at a baseband digital power detector;
up converting the digitized summed signal responsive to the receiving;
detecting the up-converted signal at the wideband power detector; and
determining a ratio of the up-converted signal to the digitized summed signal to determine the health of the radio frequency up-convert path.
12. The method of claim 11 , wherein determining a ratio of the up-converted signals to the digitized summed signal comprises:
sending information indicative of the digitized summed signal from the baseband digital power detector to the host unit controller;
sending information indicative of the up-converted signal from the wideband power detector to the host unit controller; and
comparing the information indicative of the up-converted signals to the information indicative of the digitized summed signals.