Method and apparatus for a multi-antenna device that uses a single baseband filter and analog-to-digital converter

A multi-antenna device comprising:

• a plurality of antennas;
• a plurality of receivers, each linked to one of the antennas in a one-to-one manner;
• a multiplexer configured to generate a composite analog signal from a plurality of different analog radio frequency (RF) signals, one received from different ones of the plurality of antennas;
• a baseband filter for filtering the composite analog signal;
• an analog to digital converter for converting the previously filtered composite analog signal after being filtered by the baseband filter into a composite digital signal;
• and
• a de-multiplexer configured to generate a plurality of different digital signals from the composite digital signal produced by the analog to digital converter, wherein each of the different digital signals corresponds to one of the different analog RF signals in a one-to-one manner;
• and
• wherein the multiplexer is for modifying a plurality of received analog RF signals from the receivers to frequency shift each of the analog RF signals to a different frequency range that is referenced against a baseband, wherein a frequency range of the composite analog signal generated by the multiplexer has a frequency range approximately equal to a sum of the frequency ranges of the plurality of different analog RF signals.

A method comprising:

• receiving a plurality of analog radio frequency (RF) signals from a plurality of different antennas of a multi-antenna device;
• converting the received analog RF signals into a composite analog signal;
• processing the composite analog signal through a baseband filter and an analog-to-digital converter to generate a composite digital signal;
• generating a plurality of digital signals from the composite digital signal, wherein each of the generated digital signals corresponds to one of the received analog RF signals;
• and
• wherein the composite analog signal and the composite digital signal are incoming signals to be processed by the multi-antenna device, wherein the method further comprises:
• receiving a plurality of different outgoing digital signals to be concurrently transmitted from the multi-antenna device;
• combining the different digital signals into an outgoing composite digital signal;
• converting the outgoing composite digital signal into an outgoing composite analog digital signal via a digital-to-analog converter;
• filtering results from the digital-to-analog converter through a baseband filter;
• generating a plurality of outgoing analog signals from the composite analog signal, wherein each of the generated analog signals corresponds to one of the different outgoing analog signals;
• and
• transmitting the outgoing analog signals using the plurality of different antennas, one outgoing analog signal per one of the different antennas.

A method comprising:

• receiving a plurality of analog radio frequency (RF) signals from a plurality of different antennas of a multi-antenna device;
• converting the received analog RF signals into a composite analog signal;
• processing the composite analog signal through a baseband filter and an analog-to-digital converter to generate a composite digital signal;
• generating a plurality of digital signals from the composite digital signal, wherein each of the generated digital signals corresponds to one of the received analog RF signals;
• and
• modifying each of the received analog RF signals using a plurality of local oscillators to generate a plurality of modified analog signals having a different frequency range than the received analog RF signals, wherein the modified analog signals are referenced against a common baseband and have non-overlapping ranges from each other, wherein the composite analog signal is created from the modified analog signals.

A method comprising:

• receiving a plurality of analog radio frequency (RF) signals from a plurality of different antennas of a multi-antenna device;
• converting the received analog RF signals into a composite analog signal,
• processing the composite analog signal through a baseband filter and an analog-to-digital converter to generate a composite digital signal;
• generating a plurality of digital signals from the composite digital signal, wherein each of the generated digital signals corresponds to one of the received analog RF signals;
• and
• wherein the converting modifies a frequency range of each of the analog RF signals by a signal specific offset referenced against a baseband, wherein the method further comprises:
• executing a set of algorithms, one execution to generate each of the plurality digital signals from the composite digital signal, wherein each of the algorithms subtracts an offset quantity from values in a composite digital signal from a range of the composite digital signal, where the range of the composite digital signal corresponds to a range associated with and unique to a specific one of the analog RF signals, wherein the offset quantity corresponds to a frequency offset associated with and unique to a signal specific offset of one of the analog RF signals.

A method for converting signals from analog to digital in a multi-antenna device comprising:

• receiving at a first antenna and a first receiver of a device a first analog signal;
• modifying the first analog signal using a first local oscillator to generate a first modified analog signal having a first frequency range referenced against a baseband, wherein the modifying results in a first frequency shift by a first offset quantity;
• receiving at a second antenna and a second receiver of the device a second analog signal;
• modifying the second analog signal using a second local oscillator to generate a second modified analog signal having a second frequency range referenced against the baseband, wherein the modifying results in a second frequency shift by a second offset quantity;
• forming a composite analog signal from the first modified analog signal and the second modified analog signal, where the composite analog signal has a frequency range greater than either the first frequency range or the second frequency range;
• processing the composite analog signal through a single baseband filter;
• processing the filtered composite analog signal through a single analog to digital converter to generate a composite digital signal;
• executing an algorithm that produces a first digital signal by subtracting the first offset quantity from values in the first frequency range of the composite digital signal, wherein the first digital signal represents a converted form of the first analog signal;
• and
• executing an algorithm that produces a second digital signal by subtracting the second offset quantity from values in the second frequency range of the composite digital signal, wherein the second digital signal represents a converted form of the second analog signal;
• wherein a single baseband filtering operation and a single analog-to-digital conversion operation is performed to produce the first digital signal and the second digital signal given the first analog signal and the second analog signal.