OFDM Base Station Resource Allocation via CSI Compensation
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Solution Overview
Problem
Existing OFDM systems face high packet error ratios and increased power consumption due to inaccurate channel state information (CSI) and lack of consideration for the trade-off between power and time delay in resource allocation algorithms.
Innovation Solution
A resource allocation method that dynamically adjusts rate and power by acquiring CSI, determining a compensation factor using the inverse cumulative distribution function of a non-central chi-square random variable, and applying a generalized dynamic back pressure algorithm to minimize power consumption while controlling packet error ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing resource allocation algorithms are used in OFDM systems, then system throughput can be maintained, but packet error ratio increases due to inaccurate CSI
Solution Approach 1:
The patent applies preliminary action by pre-calculating the compensation factor based on the statistical distribution characteristics of channel estimation errors. The inverse cumulative distribution function of the non-central chi-square distribution is computed in advance to determine the compensation factor that will be applied to the CSI, thereby proactively compensating for the inaccuracy before it affects packet transmission and reducing packet error ratio
Solution Approach 2:
The patent changes the parameter of CSI by introducing a compensation factor derived from the inverse cumulative distribution function. This transforms the original inaccurate CSI into a compensated CSI that accounts for estimation errors, thereby improving reliability without requiring more accurate measurement
2Use of energy by stationary object
If traditional resource allocation methods are used, then data transmission can be performed, but total power consumption of the base station increases
Solution Approach 1:
The patent changes the power allocation parameter by introducing a power-saving factor that is computed based on the compensated CSI and queue state information. This factor optimizes the power level for each user and subcarrier, thereby reducing total base station power consumption while maintaining acceptable data transmission efficiency through the generalized dynamic back pressure algorithm
Solution Approach 2:
The patent applies dynamics by implementing a dynamic resource allocation mechanism that adjusts power, rate, and resource blocks in real-time based on current channel conditions and queue states. The generalized dynamic back pressure algorithm continuously optimizes allocation decisions, enabling the system to adapt to changing conditions and reduce power consumption without sacrificing transmission efficiency
3Productivity
If ideal RRM algorithm assumptions are made, then system capacity can be optimized, but packet error probability cannot approach zero due to CSIT inaccuracy
Solution Approach 1:
The patent applies preliminary action by pre-compensating for CSIT inaccuracy through the compensation factor derived from the inverse cumulative distribution function. This preliminary compensation ensures that subsequent resource allocation decisions are based on more accurate effective CSI, allowing the system to achieve both high capacity and low packet error probability
Solution Approach 2:
The patent implements feedback by using queue state information and compensated CSI to continuously refine resource allocation decisions. The generalized dynamic back pressure algorithm uses this feedback to adjust rate and power allocations, ensuring that system capacity is optimized while packet error probability approaches zero through iterative improvement
Data Source
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AI summary
A resource allocation method and a base station in an orthogonal frequency division multiplexing system are used by a base station to allocate a resource. The method in embodiments of the present invention includes: acquiring, by the base station, channel state information CSI of a current scheduling timeslot; obtaining a compensation factor according to the CSI and a preset packet error ratio, where the compensation factor is a value corresponding to the preset packet error ratio in an inverse cumulative distribution function of a non-central chi-square random variable and a non-central parameter; replacing the CSI with the compensation factor, and determining a functional relationship between rate and power of sending data by the base station if a packet error ratio of the base station is less than or equal to the preset packet error ratio; and determining, according to the functional relationship and a generalized dynamic back pressure algorithm, the rate and total power of sending data by the base station, so as to minimize the total power of the base station. Through the embodiments of the present invention, an impact on the packet error ratio caused by inaccuracy of non-ideal CSI can be effectively reduced, and the rate and the power of sending data are determined on the basis of considering a power-time delay trade-off relationship when the base station sends data, thereby reducing total power consumption.