Frequency shifting a communications signal(s) in a multi-frequency distributed antenna system (DAS) to avoid or reduce frequency interference

摘要

Frequency shifting a communications signal(s) in a multiple frequency (multi-frequency) distributed antenna system (DAS) to avoid or reduce frequency interference is disclosed. Related devices, methods, and DASs are disclosed. Non-limiting examples of frequency interference include frequency band interference and frequency channel interference. As a non-limiting example, frequency interference in a multi-frequency DAS may result from non-linearity of a signal processing component generating an out-of-band harmonic of a first, in-use communications signal in a first frequency band, within different frequency band(s) of other in-use communications signal(s). To avoid or reduce such interference, embodiments disclosed herein involve predicting frequency interference that may result from processing received, in-use communications signals in multiple frequency bands to be distributed in a multi-frequency DAS. Frequency shifting is performed to avoid or reduce any interfering signal products produced from the signal processing of any in-use communications signals, from interfering in the frequencies of other in-use communications signals.

主权项

1. A frequency interference prediction system in a multiple frequency (multi-frequency) distributed antenna system (DAS), comprising:
a communications signal interface, comprising:
a first communications signal interface configured to receive at least one first communications signal in at least one first frequency range; anda second communications signal interface configured to receive at least one second communications signal in at least one second frequency range different from the at least one first frequency range; a first communications signal path communicatively coupled to the first communications signal interface, the first communications signal path comprising:
a first frequency shifting circuit configured to frequency shift the at least one first communications signal from a first frequency in the at least one first frequency range to a shifted first communications signal at a shifted first frequency based on a first frequency control signal; a second communications signal path communicatively coupled to the second communications signal interface and configured to provide the at least one second communications signal as an output second communications signal to a second communications signal path output; a combiner communicatively coupled to a first communications signal path output and the second communications signal path output, the combiner configured to combine an output first communications signal and the output second communications signal into a combined multi-frequency communications signal; and a controller configured to:
predict frequency interference in the combined multi-frequency communications signal; andif frequency interference is predicted in the combined multi-frequency communications signal:
determine the shifted first frequency to shift the at least one first communications signal in the combined multi-frequency communications signal; andset the first frequency control signal to cause the first frequency shifting circuit to frequency shift the at least one first communications signal to the shifted first communications signal at the shifted first frequency.