Configurable integrated radio processor

• US 9,125,054 B2
• Filed: 06/18/2012
• Issued: 09/01/2015
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Ryan, Timothy
• Primary Examiner(s): Jiang, Charles C
• Assistant Examiner(s): DEFAUW, THAD N
• Application Number:
  US13/526,237
• Publication Number:
  US 20130250865A1
• Time in Patent Office: 1,170 Days
• Field of Search: 370/329
• US Class Current: 1/1
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 88/085 Access point devices with remote components

Abstract

In a base station, a configurable radio unit allows for communication with a baseband processor that satisfies a CPRI standard while allowing personalization and customization by the end user in order to prevent undesired usage and/or access by other users/competitors. The radio module is programmable to allow for specific designation of the location, lengths, and types of signal and control information within CPRI basic frames. By being configured to allow for the adjustment of these parameters, the radio module can be commonly and mass produced while allowing for end users of the processors to personalize their use without additional hardware components, such as FPGA circuits. In addition, by generating a container frame, the radio module can allow for asynchronous communication between the CPRI standard and an employed communication scheme.

Claims

1. A configurable radio unit capable of receiving information from a baseband processor via a common public radio interface (CPRI) standard, the radio unit comprising:

a memory that stores a user-defined first subset of contiguous bits, a user-defined second subset of contiguous bits, and at least one of a user-defined line rate and a user-defined frame length; and

one or more processors and/or circuits, including;

a CPRI framer module configured to generate, from the information received from the baseband processor, a stream of CPRI basic frames based on the at least one of the user-defined line rate and the user-defined frame length;

a protocol pump module configured to extract the user-defined first subset of contiguous bits from consecutive CPRI basic frames of the CPRI basic frame stream corresponding to quadrature signal information; and

a control channel module configured to extract the user-defined second subset of contiguous bits from the consecutive CPRI basic frames of the CPRI basic frame stream corresponding to control channel information.

2. The configurable radio unit of claim 1, wherein the CPRI framer module is configured to operate at the user-defined line rate other than a standard line rate defined by the CPRI standard, and

wherein the CPRI framer module is configured to operate at the user-defined frame length other than a standard frame length defined by the CPRI standard.

3. The configurable radio unit of claim 1, the protocol pump module including:

a bit pump module configured to extract the user-defined first subset of contiguous bits; and

a protocol framer module configured to organize the extracted first subset of contiguous bits as in-phase and quadrature samples of a quadrature data signal.

4. The configurable radio unit of claim 3, wherein the bit pump module is configured to be programmed with a starting bit and a length for defining the user-defined first subset of contiguous bits, and

wherein the bit pump module is configured to extract the first subset of contiguous bits from each of the CPRI basic frames beginning at the programmed starting bit and having a number of bits equal to the programmed length.

5. The configurable radio unit of claim 4, wherein the bit pump module generates, by extracting the first subset of contiguous bits from each of consecutive CPRI basic frames, a constant bandwidth serial data stream.

6. The configurable radio unit of claim 3, wherein the protocol framer module is configured to, when the radio unit employs a communication scheme that operates at a sample rate that is an integer multiple of a basic frame rate of the CPRI basic frame stream, cause the bit pump module to extract an integer number of the in-phase and the quadrature samples from each of the consecutive CPRI basic frames.

7. The configurable radio unit of claim 6, wherein the protocol framer module is configured to, when the radio unit employs a communication scheme that operates at a sample rate that is not an integer multiple of the basic frame rate of the CPRI basic frame stream, generate a container frame for organizing an integer multiple of the in-phase and the quadrature samples based on the first subset of contiguous bits extracted by the bit pump module.

8. The configurable radio unit of claim 1, the control channel module including:

a bit pump module configured to extract the user-defined second subset of contiguous bits from consecutive CPRI basic frames as control channel information of a virtual control channel frame;

a plurality of data modules configured to process various groups of information contained within the virtual control channel frame; and

a sub-channel demultiplexer configured to be programmable with locations of the various groups of information within the virtual control channel frame, and to direct the various groups of information as they are received from the bit pump module to corresponding ones of the plurality of data modules.

20. The configurable radio unit of claim 1, wherein the line rate, the frame length, the first subset of contiguous bits, and the second subset of contiguous bits are proprietary.

9. A configurable radio unit capable of receiving information from a baseband processor via a common public radio interface (CPRI) standard using a selected communication scheme and processing the received information for transmission to a wireless communication environment, the radio unit comprising:

one or more processors and/or circuits, comprising;

a CPRI framer module configured to generate, from the information received from the baseband processor, a stream of CPRI basic frames having a standard CPRI basic frame rate; and

a protocol pump module configured to extract a subset of contiguous bits from consecutive CPRI basic frames of the CPRI basic frame stream representative of quadrature signal information,

wherein the selected communication scheme employs a sample rate that is not an integer multiple of the standard CPRI basic frame rate.

10. The configurable radio unit of claim 9, the protocol pump comprising:

a protocol framer module configured to generate a container frame for organizing an integer number of in-phase and quadrature samples of the quadrature signal information and identifying a number of bits to be extracted from each CPRI basic frame of the CPRI basic frame stream; and

a bit pump module configured to extract a number of bits from each CPRI basic frame equal to a ceiling of the number of bits.

11. The configurable radio unit of claim 10, wherein the protocol framer module is configured to generate the container frame by determining a least common multiple of the communication scheme sample rate and the CPRI basic frame rate, sizing the container frame based on the determined least common multiple, and organizing the extracted subsets of contiguous bits into a plurality of in-phase/quadrature symbols.

12. The configurable radio unit of claim 11, wherein the protocol framer module generates the container frame to have a plurality of leading stuffing bits and a plurality of trailing stuffing bits that bookend the plurality of in-phase/quadrature symbols, and

wherein the protocol framer module organizes the extracted subsets of contiguous bits into the plurality of in-phase/quadrature symbols such that each of the plurality of in-phase/quadrature symbols includes at least one symbol stuffing bit.

13. The configurable radio unit of claim 11, wherein each of the plurality of in-phase/quadrature symbols includes at least one data sample designated for a first communication channel and at least one data sample designated for a second communication channel.

14. The configurable radio unit of claim 11, wherein the protocol framer module is configured to, when a slipping between the communication scheme sample rate and the CPRI basic frame rate is detected, modify a size of the container frame by a size of at least one CPRI basic frame.

15. A method for transmitting signal data contained within a common public radio interface (CPRI) basic frame stream when employing a CPRI communication scheme whose sample rate is other than an integer multiple of a CPRI basic frame rate of the CPRI basic frame stream, the method comprising:

calculating a least common multiple of the CPRI communication scheme sample rate and the CPRI basic frame rate;

generating a container frame based on the calculated least common multiple;

extracting a subset of bits from continuous CPRI basic frames of the CPRI basic frame stream;

organizing the extracted subsets of bits into a plurality of in-phase/quadrature symbols within the container frame;

buffering the container frame for transmission;

detecting clock slipping based on a clock associated with the communication scheme and a clock associated with the CPRI basic frame stream; and

compensating for the clock slipping after the clock slipping has been detected, the compensating including increasing or decreasing a size of the container frame by a size of at least one CPRI basic frame.

16. The method of claim 15, wherein the organizing of the extracted subsets of bits into the plurality of in-phase/quadrature symbols includes placing at least one symbol stuffing bit into each in-phase/quadrature symbol, and

wherein the generating of the container frame includes placing a plurality of leading stuffing bits at the beginning of the container frame and a plurality of trailing stuffing bits at the end of the container frame that bookend the plurality of in-phase/quadrature symbols.

17. The method of claim 15, wherein the organizing of the extracted subsets of bits into the plurality of in-phase/quadrature symbols includes placing at least one data sample designated for a first communication channel and at least one data sample designated for a second communication channel in each of the plurality of in-phase/quadrature symbols.

18. The method of claim 15, wherein the detecting determines the clock slipping to be an overflow scenario when at least one of the communication scheme clock is running slower than expected and the CPRI clock is running faster than expected, or to be an underflow scenario when at least one of the communication scheme clock is running faster than expected and the CPRI clock is miming slower than expected.

19. The method of claim 18, wherein the compensating for the clock slipping includes increasing or decreasing the size of the container frame by size of at least one CPRI basic frame depending on whether an overflow scenario or an underflow scenario has been detected.