Baseband Signal Compression for CPRI and OBSAI Link Capacity

Solution Overview

Problem

Current transceiver systems in wireless communication networks face challenges in managing increasing data volumes and evolving standards, leading to the need for costly hardware upgrades, particularly in terms of serial data link capacity and resource conservation, without compliance with existing standards like OBSAI and CPRI which do not support signal sample compression.

Innovation Solution

The method involves compressing signal samples at the RF or baseband processor units before transfer over serial data links, formatting them for compatibility with existing protocols, and decompressing them at the receiving end to maintain signal processing integrity, using compressors and decompressors integrated into the system to manage data transfer efficiently.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If signal samples are transmitted uncompressed over serial data links, then data transfer capacity is maintained at current levels, but hardware upgrades become necessary to handle increasing data volumes

Engineering Contradiction:

Improvedata transfer capacityVSAvoiddata volume

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

The patent applies compression algorithms that change the parameter of data representation, transforming full-precision signal samples into compressed formats with fewer bits per sample. This parameter change reduces the quantity of data transmitted while preserving essential signal information, thereby increasing effective data transfer capacity without requiring hardware upgrades.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a compressed representation (copy) of the original signal samples that contains the essential information in a more compact form. This compressed copy is transmitted over the serial data link, reducing the data volume while maintaining the ability to reconstruct the original signal for processing.

Inventive Principle:

Principle #26Copying

2Quantity of substance

If compression is implemented to reduce data volume, then hardware upgrades are postponed, but compatibility with existing standards like OBSAI and CPRI is compromised

Engineering Contradiction:

Improvedata volumeVSAvoidstandard compliance

Core Design Contradiction:

Quantity of substanceVSAdaptability or versatility

Solution Approach 1:

The patent introduces formatting layers as intermediaries between the compression algorithm and the serial data link interface. These formatters translate compressed data into formats that are compatible with existing standards like OBSAI and CPRI, acting as a mediator that allows compression to be used without breaking standard compliance. The formatting layer ensures that the compressed data can be properly transmitted and reconstructed according to standard protocols.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Productivity

If more serial data link capacity is provided to handle increasing data volumes, then data transfer capacity increases, but system cost increases due to hardware upgrades

Engineering Contradiction:

Improvedata transfer capacityVSAvoidsystem cost

Core Design Contradiction:

ProductivityVSLoss of energy

Solution Approach 1:

The patent creates a compressed representation (copy) of the original signal samples that contains the essential information in a more compact form. This compressed copy is transmitted over the serial data link, reducing the data volume while maintaining the ability to reconstruct the original signal for processing.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent applies compression algorithms that change the parameter of data representation, transforming full-precision signal samples into compressed formats with fewer bits per sample. This parameter change reduces the quantity of data transmitted while preserving essential signal information, thereby increasing effective data transfer capacity without requiring hardware upgrades.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS8320433B2Compression of baseband signals in base transceiver system interfaces

Publication Date: 2012.11.27 INTEGRATED DEVICE TECH INC

AI summary

A signal compression method and apparatus for a base transceiver system (BTS) in a wireless communication network provides efficient transfer of compressed signal samples over serial data links in the system. For the uplink, an RF unit of the BTS compresses baseband signal samples resulting from analog to digital conversion of a received analog signal followed by digital downconversion. The compressed signal samples are transferred over the serial data link to the baseband processor then decompressed prior to normal signal processing. For the downlink, the baseband processor compresses baseband signal samples and transfers the compressed signal samples to the RF unit. The RF unit decompresses the compressed samples prior to digital upconversion and digital to analog conversion to form an analog signal for transmission over an antenna. Compression and decompression can be incorporated into operations of conventional base stations and distributed antenna systems, including OBSAI or CPRI compliant systems.