Improved Matching-Pursuit Implementation for LTE Channel Estimation

An implementation of a reduced complexity matching pursuit channel estimator for LTE is presented. The design contains an FFT/IFFT module with non-radix-2 units and a core estimator. The module is flexible enough to perform FFT and IFFT at different resolutions needed, using the same hardware. Based on prior work the needed internal word lengths are found. Internal shifts are employed to maximize the use of available resources. The design is implemented in a 65 nm low power process from STMicroelectronics. The total area of the implementation is 1 mm² design, including input pads and extra control logic. The algorithmic improvements reduce the complexity by up to 56% compared to prior art. At the same time estimator shows great improvement in speed, allowing over 6 times the number of estimations in the same time. Power consumption of the estimator is simulated to ~ 20 mW, running at 70 MHz.