System-wide uplink band gain control in a distributed antenna system (DAS), based on per-band gain control of remote uplink paths in remote units

• US 9,788,279 B2
• Filed: 08/16/2016
• Issued: 10/10/2017
• Est. Priority Date: 09/25/2014
• Status: Active Grant

• Current Assignee: Corning Optical Communications LLC (Corning Incorporated)
• Original Assignee: Corning Optical Communications Wireless Ltd. (Corning Incorporated)
• Inventors: Henia, Yoni
• Primary Examiner(s): VO, NGUYEN THANH
• Application Number:
  US15/237,917
• Publication Number:
  US 20160360490A1
• Time in Patent Office: 420 Days
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 10/25753 Distribution optical network, e.g. between a base station and a plurality of remote units
• CPC Class Codes: H04B 17/13 of power amplifiers, e.g. gain or non-linearity
• CPC Class Codes: H04B 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• CPC Class Codes: H04W 52/146 Uplink power control
• CPC Class Codes: H04W 52/52 using AGC [Automatic Gain Control] circuits or amplifiers

Abstract

System-wide uplink band gain control in a distributed antenna system (DAS) based on per-band gain control of remote uplink paths in remote units is disclosed. In one embodiment, for each uplink band in the DAS, a gain control system receives remote uplink band power measurements for each remote uplink path for the uplink band. Based on these power measurements, the gain control system determines if the uplink gain of all of the remote uplink paths of the plurality of uplink paths of the uplink band should be adjusted. If the uplink gain of the remote uplink paths of the uplink band should be adjusted, the gain control system directs a remote uplink gain control circuit for each remote uplink path of the uplink band to adjust the uplink gain by a defined remote uplink band gain level.

Claims

1. A wireless communication system, comprising:

a central unit configured to;

receive at least one downlink communications signal from a network;

distribute the received at least one downlink communications signal to a plurality of remote units;

receive a plurality of uplink communications signals from the plurality of remote units;

combine the received plurality of uplink communications signals into a combined uplink communications signal in a central uplink path; and

distribute the received plurality of uplink communications signals to the network;

the plurality of remote units each comprising;

a plurality of remote uplink band power measurement circuits each coupled to a remote uplink path among a plurality of remote uplink paths each carrying at least one uplink band communications signal in a remote unit, each remote uplink band power measurement circuit among the plurality of remote uplink band power measurement circuits configured to;

measure a remote uplink band power of an uplink band communications signal in the remote uplink path in the remote unit; and

provide a remote uplink band power measurement indicative of the measured remote uplink band power of the uplink band communications signal in the remote uplink path;

each remote unit configured to;

receive the at least one downlink communications signal from the central unit;

distribute the received at least one downlink communications signal to at least one client device;

receive at least one uplink communications signal among the plurality of uplink communications signals in at least one remote uplink path from the at least one client device; and

distribute the received at least one uplink communications signal among the plurality of uplink communications signals to the central unit; and

a central controller configured to;

for each uplink band in the wireless communication system;

(i) receive the remote uplink band power measurement for each remote uplink path for the uplink band;

(ii) determine if an uplink gain of the remote uplink paths of the plurality of remote uplink paths of the uplink band should be adjusted; and

(iii) if the uplink gain of the remote uplink paths of the plurality of remote uplink paths of the uplink band should be adjusted;

direct a remote uplink gain control circuit for each remote uplink path of the uplink band to adjust the uplink gain of the respective remote uplink path by a defined remote uplink band gain level.

2. The wireless communication system of claim 1, wherein the central controller is configured to repeatedly perform tasks (i)-(iii).

3. The wireless communication system of claim 2, wherein the central controller is further configured to, for each uplink band of a plurality of uplink bands in the wireless communication system:

identify as high power remote uplink paths, the remote uplink paths of the plurality of remote uplink paths of the uplink band having a remote uplink band power measurement above a remote uplink threshold power level;

if a number of remote uplink paths of the plurality of remote uplink paths of the uplink band that were identified as high power remote uplink paths is less than a second high power remote uplink path threshold level;

direct the remote uplink gain control circuit for each remote uplink path of the uplink band, to increase the uplink gain of the respective remote uplink path by the defined remote uplink band gain level.

4. The wireless communication system of claim 1, wherein the central unit is configured to receive the plurality of uplink communications signals comprised of a plurality of optical uplink communications signals from the plurality of remote units;

the central unit further comprising a plurality of central optical-to-electrical (O-E) converters each configured to convert a received optical uplink communications signal among the plurality of optical uplink communications signals to an electrical uplink communications signal to provide a plurality of electrical uplink communications signals;

the central unit configured to combine the received plurality of electrical uplink communications signals into a combined electrical uplink communications signal in the central uplink path.

5. The wireless communication system of claim 1, wherein the central controller is configured to determine if the uplink gain of the remote uplink paths of the uplink band should be adjusted by being configured to:

identify as high power remote uplink paths, any remote uplink paths of the plurality of remote uplink paths of the uplink band that have a remote uplink band power measurement above a remote uplink threshold power level; and

if a number of remote uplink paths of the plurality of remote uplink paths of the uplink band identified as high power remote uplink paths exceeds a high power remote uplink path threshold level, direct the remote uplink gain control circuit for each remote uplink path of the uplink band to reduce the uplink gain of the respective remote uplink path by the defined remote uplink band gain level.

6. The wireless communication system of claim 5, wherein the central controller is configured to repeatedly perform tasks (i)-(iii).

7. The wireless communication system of claim 6, wherein the central controller is further configured to, for each uplink band of a plurality of uplink bands in the wireless communication system:

if a number of remote uplink paths of the plurality of remote uplink paths of the uplink band that were identified as high power remote uplink paths is less than a second high power remote uplink path threshold level;

direct the remote uplink gain control circuit for each remote uplink path of the uplink band, to increase the uplink gain of the respective remote uplink path by the defined remote uplink band gain level.

8. The wireless communication system of claim 1, wherein the central controller is configured to determine if the uplink gain of the remote uplink paths of the uplink band should be adjusted by being configured to:

identify as high power remote uplink paths, any remote uplink paths of the plurality of remote uplink paths of the uplink band that have a remote uplink band power measurement above a remote uplink threshold power level; and

if a number of remote uplink paths of the plurality of remote uplink paths of the uplink band identified as high power remote uplink paths is less than a second high power remote uplink path threshold level, direct the remote uplink gain control circuit for each remote uplink path of the uplink band to increase the uplink gain of the respective remote uplink path by the defined remote uplink band gain level.

9. The wireless communication system of claim 8, wherein the central controller is configured to repeatedly perform tasks (i)-(iii).

10. The wireless communication system of claim 8, wherein the central controller is further configured to:

for each uplink band of a plurality of uplink bands in the wireless communication system;

if a number of remote uplink paths of the plurality of remote uplink paths of the uplink band that were identified as high power remote uplink paths is less than a second high power remote uplink path threshold level;

direct the remote uplink gain control circuit for each remote uplink path of the uplink band, to increase the uplink gain of the respective remote uplink path by the defined remote uplink band gain level.

11. The wireless communication system of claim 1, wherein:

the central unit is configured to;

distribute the received at least one downlink communications signal over a plurality of downlink communications medium to the plurality of remote units; and

receive an uplink communications signal among the received plurality of uplink communications signals over an uplink communications medium among a plurality of uplink communications medium from each remote unit among the plurality of remote units;

each remote unit among the plurality of remote units is communicatively coupled to a downlink communications medium among the plurality of downlink communications medium, and communicatively coupled to an uplink communications medium among the plurality of uplink communications medium;

the plurality of remote units each configured to;

receive the at least one downlink communications signal over a downlink communications medium among the plurality of downlink communications medium from the central unit; and

distribute the received at least one uplink communications signal among the plurality of uplink communications signals over an uplink communications medium among the plurality of uplink communications medium to the central unit.

12. The wireless communication system of claim 11, wherein each downlink communications medium among the plurality of downlink communications medium communicatively coupled to a remote unit among the plurality of remote units, and the uplink communications medium among the plurality of uplink communications medium communicatively coupled to the remote unit among the plurality of remote units, are comprised of a common communications medium.

13. The wireless communication system of claim 11, wherein the central unit is configured to receive the plurality of uplink communications signals comprised of a plurality of optical uplink communications signals from the plurality of remote units;

the central unit further comprising a plurality of central optical-to-electrical (O-E) converters each configured to convert a received optical uplink communications signal among the plurality of optical uplink communications signals to an electrical uplink communications signal to provide a plurality of electrical uplink communications signals;

the central unit configured to combine the received plurality of electrical uplink communications signals into a combined electrical uplink communications signal in the central uplink path.

14. The wireless communication system of claim 1, wherein the plurality of remote units are each configured to receive the at least one uplink communications signal among the plurality of uplink communications signals comprised of at least one electrical uplink communications signal among a plurality of electrical uplink communications signals in the at least one remote uplink path from the at least one client device;

each remote uplink band power measurement circuit configured to;

measure remote uplink power of the at least one electrical uplink communications signal in the at least one remote uplink path; and

provide at least one remote uplink power measurement indicative of the remote uplink power of the at least one electrical uplink communications signal in the at least one remote uplink path;

each of the plurality of remote units further comprising at least one electrical-to-optical (E-O) converter configured to convert the received at least one electrical uplink communications signal to at least one optical uplink communications signal;

wherein each of the plurality of remote units is configured to distribute the received at least one optical uplink communications signal among a plurality of optical uplink communications signals to the central unit.

15. The wireless communication system of claim 1, wherein:

each remote uplink gain control circuit comprises a remote uplink automatic level control (ALC) circuit further configured to limit a remote uplink power level of the remote uplink path based on a remote uplink gain adjustment signal received from the central controller; and

the central controller is configured to identify as high power remote uplink paths the remote uplink paths of the plurality of remote uplink paths of the uplink band that have activated the remote uplink ALC circuit.

16. The wireless communication system of claim 1, wherein the defined remote uplink band gain level is lower than 10 dB.

17. The wireless communication system of claim 1, wherein the defined remote uplink band gain level is approximately 1 dB.

18. The wireless communication system of claim 1, wherein the central controller is further configured to set the uplink gain of the plurality of remote uplink paths to an initial remote uplink band gain level before performing tasks (i)-(iii).

19. The wireless communication system of claim 18, wherein the initial remote uplink band gain level is comprised of a maximum remote uplink band gain level.

20. The wireless communication system of claim 1, wherein the maximum remote uplink band gain level is approximately 10 dB up to 30 dB.