Method and apparatus for uplink coverage improvement
A method and apparatus for an uplink signal processing system that includes converting a plurality of received RF signals which can be grouped by common diversity characteristics into the digital domain, and performing signal processing on the signals to maximize the signal to noise ratio, when the signals common to a diversity characteristic are combined. The signals are then combined and converted back to RF, to conventionally provide a base station with a main and diversity channel.
1 . A method of combining signals in the receive path of a wireless communications system, comprising the steps of:
(a) receiving a plurality of RF signals corresponding to a common diversity characteristic through a plurality of corresponding antenna elements;
(b) converting the received RF signals into electronic digital signals; and
(c) combining the converted signals into composite signals representative of the diversity characteristic;
wherein the step of combining is optimized for signal quality.
2 . A method according to claim 1 , further comprising the steps of:
(d) converting the converted composite signals into analog signals; and
(e) sending the signals to a base station.
3 . A method according to claim 1 , wherein the step of combining uses diversity combining.
4 . A method according to claim 1 , wherein the step of combining uses minimum mean square error.
5 . A method according to claim 1 , wherein the step of combining uses maximum ratio combining.
6 . A method according to claim 1 , further comprising the step of repeating steps (a) through (c) in respect of a second plurality of RF signals corresponding to a different common diversity characteristic.
7 . A receiver system for wireless communications, comprising:
a plurality of analog to digital converters each adapted to be coupled to a corresponding antenna element for receiving RF signals corresponding to a common diversity characteristic for converting the received RF signals into digital signals; and
an optimizing combiner coupled to the analog to digital converters for combining the digital signals into a composite signal representative of the diversity characteristic;
wherein the optimizing combiner combines the signals in such a manner that they are optimized for signal quality.
8 . A receiver system for wireless communications according to claim 7 , further comprising:
digital to analog converters coupled to the optimizing combiner for converting the composite signals into an analog signal; and
an output port coupled to the digital to analog converters for sending the composite analog signal to a base station.
9 . A receiver system for wireless communications according to claim 7 , wherein said system is adapted to be interposed between the antenna elements and a base station.
10 . A receiver system for wireless communications according to claim 7 , wherein said optimizing combiner further comprises a diversity combiner.
11 . A receiver system for wireless communications according to claim 10 , wherein said optimizing combiner further comprises a maximum ratio combiner.
12 . A receiver system for wireless communications according to claim 10 , wherein said optimizing combiner further comprises a minimum mean square error combiner.
13 . A receiving system for wireless communications according to claim 7 , further comprising at least one additional plurality of antenna elements for receiving RF signals corresponding to a different common diversity characteristic, and corresponding analog to digital converters and optimizing combiner with respect to each additional plurality of antenna elements coupled thereto.
14 . A receiver system for wireless communications according to claim 13 , wherein the plurality of analog to digital converters numbers eight.
15 . An RF signal processor, comprising:
a plurality of input ports for receiving antenna signals corresponding to a common diversity characteristic;
at least one analog to digital converter coupled to said input ports for transforming the antenna signals into digital form; and
an optimizing combiner coupled to the at least one analog to digital converter for combining the digital signals into a composite signal representative of a common diversity characteristic;
wherein the optimizing combiner combines the signals in such a manner that they are optimized for signal quality.
16 . An RF signal processor according to claim 15 , further comprising:
at least one digital to analog converter coupled to the optimizing combiner for converting the composite signal into an analog signal;
an output port coupled to the digital to analog converters for sending the composite analog signal to a base station.
17 . An RF signal processor according to claim 15 , wherein said optimizing combiner further comprises a diversity combiner.
18 . An RF signal processor according to claim 15 , wherein said optimizing combiner further comprises a maximum ratio combiner.
19 . An RF signal processor according to claim 15 , wherein said optimizing combiner further comprises a minimum mean square error combiner.
20 . An RF signal processor according to claim 15 , wherein there are eight antenna signals.
21 . An RF signal processor according to claim 15 , further comprising:
a plurality of groups of input ports for receiving antenna signals, each group corresponding to a group of antenna signals having a common diversity characteristic; and
an optimizing combiner coupled to the at least one analog to digital converter for combining each group of digital signals into composite signals representative of each group's common diversity characteristic.
22 . An RF signal processor according to claim 21 further comprising:
at least one digital to analog converter coupled to the optimizing combiner for converting the composite signals into analog signals;
a plurality of output ports coupled to the digital to analog converters for sending the composite analog signals to a base station.
23 . An RF signal processor according to claim 22 , wherein the composite analog signals correspond to a main and diversity channel for a base station.