Method and system for CPRI cascading in distributed radio head architectures

• US 8,467,823 B2
• Filed: 03/24/2010
• Issued: 06/18/2013
• Est. Priority Date: 03/24/2010
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Seki, Hiroyuki, Chen, Wei-Peng, Zhu, Chenxi, Mao, Nien-Tai Kai, Kiyanagi, Hiroyuki
• Primary Examiner(s): Safaipour, Bobbak
• Application Number:
  US12/731,052
• Publication Number:
  US 20110237178A1
• Time in Patent Office: 1,182 Days
• Field of Search: 455/453, 455/436, 455/524, 370/328, 370/331
• US Class Current: 455/524
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

A method of communicating between a base band unit and a plurality of remote radio heads includes the steps of receiving a first signal through an antenna in a first remote radio head, transmitting the first signal to a second remote radio head through a digital radio interface, receiving a second signal through an antenna in the second remote radio head, compensating for a delay accrued in the first signal, adding the first signal and the second signal to obtain a resulting signal, and transmitting the resulting signal to a base band unit through a digital radio interface.

Claims

1. A method of communicating between a base band unit and a plurality of remote radio heads, comprising the steps of:

receiving a first signal through an antenna in a first remote radio head;

transmitting the first signal to a second remote radio head through a digital radio interface;

receiving a second signal through an antenna in the second remote radio head;

compensating for a delay accrued in the first signal;

adding the first signal and the second signal to obtain a resulting signal; and

transmitting the resulting signal to a base band unit through a digital radio interface,

wherein the digital radio interface is Common Public Radio Interface (“

CPRI”

).

2. The method of claim 1, wherein adding the first signal and the second signal to obtain a resulting signal further comprises using digital signal bits addition.

3. The method of claim 2, wherein using digital signal bits addition further comprises utilizing a fifteen-bit word.

4. The method of claim 1, wherein the first signal is compensated for the delay accrued in the first signal.

5. The method of claim 1, wherein the second signal is compensated for the delay accrued in the first signal.

6. The method of claim 1, wherein the delay accrued in the first signal comprises delay due to transmission of the first signal to the second remote radio head.

7. The method of claim 6, wherein the delay accrued in the first signal further comprises delay due to transmission of a third signal to the second remote radio head.

8. An article of manufacture comprising:

a non-transitory computer readable medium; and

computer-executable instructions carried on the non-transitory computer readable medium, the instructions readable by a processor, the instructions, when read and executed, for causing the processor to;

receive a first signal through an antenna in a first remote radio head;

transmit the first signal to a second remote radio head through a digital radio interface;

receive a second signal through an antenna in the second remote radio head;

compensate for a delay accrued in the first signal;

add the first signal and the second signal to obtain a resulting signal; and

transmit the resulting signal to a base band unit through a digital radio interface, wherein the digital radio interface is Common Public Radio Interface (“

CPRI”

).

9. The article of claim 8, wherein adding the first signal and the second signal to obtain a resulting signal further comprises using digital signal bits addition.

10. The article of claim 9, wherein using digital signal bits addition further comprises utilizing a fifteen-bit word.

11. The article of claim 8, wherein the first signal is compensated for the delay accrued in the first signal.

12. The article of claim 8, wherein the second signal is compensated for the delay accrued in the first signal.

13. The article of claim 8, wherein the delay accrued in the first signal comprises delay due to transmission of the first signal to the second remote radio head.

14. The article of claim 13, wherein the delay accrued in the first signal further comprises delay due to transmission of a third signal to the second remote radio head.