Static delay compensation in a telecommunications system

Patent metadata

Field	Value
Publication number	US-2016134353-A1
Application number	US-201514717642-A
Country	US
Kind code	A1
Filing date	May 20, 2015
Priority date	Nov 6, 2014
Publication date	May 12, 2016
Grant date	—

Abstract

Certain features relate to compensating for a roundtrip delay caused by a distributed antenna system. A delay unit communicatively coupled to a base station can intercept the delay compensation signaling communicated between the digital baseband unit of the base station and the radio transmitter unit of the base station. The delay unit can adjust the delay compensation signaling by adding to the delay compensation signaling the pre-determined fiber delay caused by the DAS. In some aspects, the delay unit can delay the control words for a base station operating under the Common Public Radio Interface standard. In other aspects, the delay unit can delay the round-trip time measurement message for a base station operating under the Open Base Station Architecture Initiative standard.

First claim

What is claimed is:

1 . A system comprising:
a distributed antenna system for being communicatively coupled to a base station, the distributed antenna system including a head-end unit and one or more remote units communicatively coupled to the head-end unit, the head-end unit being configured to transmit wireless communication data in signals from the base station to the one or more remote units that are configured to wirelessly transmit the wireless communication data to user devices; and a delay unit communicatively coupled to the base station, the delay unit being configured to introduce to the base station a delay period to control information included in a transmit frame transmitted by the base station, the delay period corresponding to a roundtrip delay caused by the distributed antenna system.

2 . The system of claim 1 , wherein the delay unit is configured to add the delay period to the control information by delaying a control byte of a Common Public Radio Interface transmit frame for a duration of the roundtrip delay caused by the distributed antenna system.

3 . The system of claim 2 , wherein the duration of the delay period includes a time period between a transmission of an internal frame start of the transmit frame transmitted from a digital baseband unit of the base station and a receipt of a receive frame start received at the digital baseband unit of the base station.

4 . The system of claim 3 , wherein the delay unit includes a ring buffer including a read pointer and a write pointer, the ring buffer being configured to store the control byte of the Common Public Radio Interface Transmit frame,
wherein a distance between the read pointer and the write pointer corresponds to the delay period.

5 . The system of claim 1 , wherein the delay unit is configured to add the delay period to the control information by deleting a round-trip time measurement message from an Open Base Station Architecture Initiative transmit signal and inserting the round-trip time measurement message after a duration of the roundtrip delay caused by the distributed antenna system.

6 . The system of claim 1 , wherein the distributed antenna system is configured to cause the roundtrip delay that is proportional to a length of a communication link between the head-end unit and the one or more remote units.

7 . The system of claim 1 , wherein the control information included in the transmit frame is part of delay compensation signaling between a digital baseband unit of the base station and a radio transmitter unit of the base station.

8 . A method, comprising:
receiving an optical signal from a radio transmitter unit of a base station, the optical signal including a first transmit frame including control information and data information; generating delayed control information by introducing a delay period to the control information for a duration of a roundtrip delay caused by a distributed antenna system; generating second transmit frame by multiplexing the delayed control information and the data information; and transmitting the second transmit frame to a digital baseband unit of the base station.

9 . The method of claim 8 , wherein introducing the delay period to the control information comprises delaying a control byte of a Common Public Radio Interface transmit frame for the duration of the roundtrip delay caused by the distributed antenna system.

10 . The method of claim 8 , wherein introducing the delay period to the control information comprises delaying a round-trip time measurement message for an Open Base Station Architecture Initiative transmit signal and inserting the round-trip time measurement message after the duration of the roundtrip delay caused by the distributed antenna system.

11 . The method of claim 9 , wherein the duration of the roundtrip delay includes a time period between a transmission of an internal frame start of a transmit frame transmitted from the digital baseband unit of the base station and a receipt of a receive frame start received at the digital baseband unit of the base station.

12 . The method of claim 8 , wherein the roundtrip delay caused by the distributed antenna system is proportional to a length of a communication link between a head-end unit and one or more remote units of the distributed antenna system.

13 . The method of claim 12 , wherein the head-end unit is configured to provide wireless communication signals from the base station to the one or more remote units and the one or more remote units are configured to provide the wireless communication signals to user devices.

14 . A head-end unit, comprising:
a first interface configured to receive and transmit, with a radio transmitter unit of a base station, signals that include wireless communication data; a second interface configured to transmit the wireless communication data from the radio transmitter unit of the base station to one or more remote units of a distributed antenna system; and a delay unit for being communicatively coupled to a digital baseband unit of the base station and the radio transmitter unit of the base station, the delay unit being configured to introduce to the base station a delay period corresponding to a roundtrip delay caused by the distributed antenna system by adding the delay period to control information included in a transmit frame transmitted to the base station.

15 . The head-end unit of claim 14 , wherein the delay unit is configured to add the delay period to the control information by delaying a control byte of a Common Public Radio Interface transmit frame for a duration of the roundtrip delay caused by the distributed antenna system.

16 . The head-end unit of claim 15 wherein the duration of the delay period includes a time period between a transmission of an internal frame start of a transmit frame transmitted from the digital baseband unit of the base station and a receipt of a receive frame start received at the digital baseband unit of the base station.

17 . The head-end unit of claim 16 , wherein the delay unit includes a ring buffer including a read pointer and a write pointer, the ring buffer configured to store the control byte of the Common Public Radio Interface Transmit frame, and wherein a distance between the read pointer and the write pointer corresponds to the delay period.

18 . The head-end unit of claim 14 , wherein the delay unit is configured to add the delay period to the control information by deleting a round-trip time measurement message from an Open Base Station Architecture Initiative transmit signal and inserting the round-trip time measurement message after a duration of the roundtrip delay caused by the distributed antenna system.

19 . The head-end unit of claim 14 , wherein the roundtrip delay caused by the distributed antenna system is proportional to a length of a communication link between the head-end unit and the one or more remote units.

20 . The head-end unit of claim 14 , wherein the control information included in the transmit frame is part of delay compensation signaling between the digital baseband unit of the base station and the radio transmitter unit of the base station.

Assignees

• Commscope Technologies Llc

Inventors

• Lange Keld Knut

Classifications

• H04J3/0682

  by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging · CPC title

• H04B10/00

  Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication · CPC title

• H04J3/0647

  Synchronisation among TDM nodes · CPC title

• H04W56/004 Primary

  compensating for timing error of reception due to propagation delay · CPC title

• H04B7/0667 Primary

  of delayed versions of same signal (using space-time coding H04L1/0618) · CPC title