Protection of distributed antenna systems

• US 9,509,133 B2
• Filed: 06/27/2014
• Issued: 11/29/2016
• Est. Priority Date: 06/27/2014
• Status: Active Grant

• Current Assignee: Corning Optical Communications LLC (Corning Incorporated)
• Original Assignee: Corning Optical Communications Wireless Ltd. (Corning Incorporated)
• Inventors: Saig, Maor, Schwartzman, Ronen
• Primary Examiner(s): Kitov, Zeev V
• Assistant Examiner(s): Comber, Kevin J
• Application Number:
  US14/317,475
• Publication Number:
  US 20150380928A1
• Time in Patent Office: 886 Days
• Field of Search: 361/54
• US Class Current: 1/1
• CPC Class Codes: H02H 7/20 for electronic equipment for converters H02H7/10; for electric measuring instruments G01R1/36; for dc voltage or current semiconductor regulators G05F1/569; for amplifiers H03F1/52; for electronic switching circuits H03K17/08
• CPC Class Codes: H02H 9/00 Emergency protective circuit arrangements for limiting excess current or voltage without disconnection
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 1/40 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: H04W 88/08 Access point devices

Abstract

A protection circuit may be configured for detecting electrical power of downlink radio frequency (RF) signals, and diverting a substantial portion of the downlink RF signals away from a downlink RF interface of a distributed antenna system DAS in response to the detected electrical power being equal to or greater than a predetermined electrical power. The downlink RF signals diverted away from the downlink RF interface may be routed to an electrical load. The protection circuit may include hysteresis.

Claims

1. A distributed antenna apparatus, comprising:

at least one downlink radio frequency (RF) interface configured to receive downlink RF signals and distribute the downlink RF signals over at least one downlink communications medium to one or more remote antenna units (RAUs);

at least one protection circuit communicatively coupled to the at least one downlink RF interface, the at least one protection circuit being configured for

detecting electrical power of at least a portion of the downlink RF signals, and

diverting a remainder portion of the downlink RF signals away from the at least one downlink RF interface in response to the detected electrical power being equal to or greater than a predetermined electrical power, wherein the remainder portion is a portion of the downlink RF signals that does not include the at least a portion of the downlink RF signals;

wherein the at least one protection circuit comprises;

at least one power detector for detecting the detected electrical power of the at least a portion of the downlink RF signals;

at least one comparator operatively associated with the at least one power detector for determining whether the detected electrical power is equal to or greater than the predetermined electrical power;

at least one RF switch operatively associated with the at least one comparator for diverting at least the remainder portion of the downlink RF signals away from the at least one downlink RF interface in response to the at least one comparator determining that the detected electrical power being equal to or greater than the predetermined electrical power; and

at least one coupler operatively associated with both the at least one power detector and the at least one RF switch, wherein;

the at least one coupler is configured for splitting the at least a portion of the downlink RF signals and the remainder portion of the downlink electrical RF signals from one another,

the at least one coupler being operatively associated with the at least one power detector comprises the at least one power detector receiving the at least a portion of the downlink electrical RF signals, and

the at least one coupler being operatively associated with the at least one RF switch comprises the at least one RF switch receiving the remainder portion of the downlink electrical RF signals.

2. The distributed antenna system apparatus of claim 1, wherein:

the at least a portion of the downlink RF signals is a sample portion of the downlink RF signals, and

the predetermined electrical power is indicative of electrical power of the downlink RF signals being in a range from 0.1 watts to 100 watts.

3. The distributed antenna system apparatus of claim 1, wherein the at least one protection circuit is configured for diverting up to 100 watts away from the at least one downlink RF interface in response to the detected electrical power being equal to or greater than the predetermined electrical power.

4. The distributed antenna system apparatus of claim 1, wherein:

the predetermined electrical power is a first predetermined electrical power; and

the at least one protection circuit comprises hysteresis so that the at least one protection circuit is configured for allowing the remainder portion of the downlink RF signals to pass through to the at least one downlink RF interface in response to the detected electrical power being equal to or less than a second predetermined electrical power that is less than the first predetermined electrical power.

5. The distributed antenna system apparatus of claim 1 in combination with a base transceiver station (BTS) for providing the downlink RF signals, wherein the at least one protection circuit is communicatively coupled to the BTS such that the at least one protection circuit is positioned between the BTS and the at least one downlink RF interface.

6. The distributed antenna system apparatus of claim 1 in combination with an electrical load, wherein the at least one protection circuit is communicatively coupled to the electrical load, and the at least one protection circuit is configured for diverting the remainder portion of the downlink RF signals to the electrical load in response to the detected electrical power being equal to or greater than the predetermined electrical power.

7. The distributed antenna system apparatus of claim 1, further comprising at least one uplink RF interface configured to receive uplink RF signals over at least one uplink communications medium from the one or more RAUs.

8. The distributed antenna system apparatus of claim 7, wherein the at least one downlink communications medium and the at least one uplink communications medium includes at least one optical fiber medium.

9. The distributed antenna system apparatus of claim 1, further comprising a digital to analog converter coupled to a first port of the comparator, and the power detector being coupled to a second port of the comparator.

10. The distributed antenna system apparatus of claim 1, wherein the at least one RF switch comprises a solid state relay.