Baseband Processor Channelization Code Power Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multipath fading causes loss of orthogonality between channelization codes in DS-CDMA systems, leading to signal interference that limits performance, capacity, and high data-rate coverage in wireless communication systems like W-CDMA, HSDPA, and CDMA2000, as conventional receivers rely on total base station power approximations rather than channel-specific power estimates.
Innovation Solution
A wireless communication device with a baseband processor estimates channelization code powers using a channelization-code based impairment correlation model, accounting for interference and noise power contributions to suppress interference and improve signal recovery, by deriving code-specific power estimates from pilot and data signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If conventional receivers use total base station power approximations, then device complexity is reduced, but measurement precision of channel-specific power estimates deteriorates
Solution Approach 1:
The patent segments the total base station power into individual channelization code power components. Instead of treating power as a single aggregate value, the receiver divides and estimates power for each channelization code separately, enabling precise measurement of individual channel powers while maintaining manageable complexity through structured processing.
Solution Approach 2:
The patent changes the parameter being measured from total base station power to channel-specific power. By transforming the power estimation parameter from a macro-level aggregate to micro-level channel-specific values, the system achieves higher measurement precision without proportionally increasing complexity.
2Productivity
If channelization code power estimation is performed without bias removal, then processing speed is maintained, but measurement precision of power estimates deteriorates due to interference and noise leakage
Solution Approach 1:
The patent applies preliminary bias removal processing to eliminate interference and noise leakage before final power estimation. By removing these biases in advance through subtraction of estimated interference and noise powers, the system achieves accurate power estimates without requiring complex iterative processing, thus maintaining processing speed.
Solution Approach 2:
The patent extracts and removes the bias components (interference power and noise power) from the total received power measurement. By separating and eliminating these unwanted components, the system obtains clean channel-specific power estimates, improving measurement precision while keeping the processing pipeline efficient.
3Device complexity
If interference and noise power are not accounted for in channelization code power estimation, then device complexity is reduced, but signal processing quality deteriorates
Solution Approach 1:
The patent applies local quality improvement by specifically addressing interference and noise removal for each channelization code individually. Instead of uniform processing, the system tailors the power estimation and bias removal to each code's specific interference and noise characteristics, enhancing signal processing quality without uniformly increasing complexity across all channels.
Data Source
AI summary
Processing in a baseband processor is improved by estimating channelization code powers when processing received signals and reducing at least one of interference and noise power from the code power estimates. According to one embodiment of a wireless communication device such as a mobile phone or Local Area Network (LAN) adapter, the device comprises circuitry configured to receive a composite signal having contributions from a signal of interest and one or more interfering signals and a baseband processor. The baseband processor is configured to estimate channelization code powers for a channelization code associated with the signal of interest and one or more channelization codes associated with the one or more interfering signals. The baseband processor is also configured to reduce at least one of interference and noise power from the channelization code power estimates.