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Efficient Model for OFDM based IEEE 802.11 Receiver with Autocorrelation technique And…
VI. CONCLUSION
The Proposed model concludes that the performance of the WLAN receiver has been enhanced by
means of Autocorrelator and CORDIC Algorithm.
Autocorrelator can perform synchronization for frame ,time and frequency. It has been also proved
that Autocorrelation is suitable for synchronization. After a careful analysis of competing algorithms, it is
decided that the best choice for time synchronization is to use the basic Auto-Correlation estimator. To get more
accuracy for estimating the frequency offsets, CORDIC algorithm is used. It is used for estimating the carrier
frequency offsets as well as compensating those frequencies by estimating the phase of the maximum
correlating signal. It is more advantageous to greatly reduces the delay while using the multiplier hardware. In
previous methods for estimating the offsets, eventhough it achieves better result it lack accuracy. But in the
proposed model, the given sample is serially iterated in order to achieve the bit of accuracy. It also achieves
minimum resource utilization.The proposed model also proved that the utility of devices is lesser than the other
existing model. In the end, the proposed design consumed an relatively low quantity of hardware resources,
gives less delay and produced excellent results for packet detection, frequency offset estimation, and time,
frequency synchronization.
VII. FUTURE WORK
By getting the better results, it is also decided that the quantized 64 sample cross correlator, in
conjunction with the maximum detector, it would be used for fine time synchronization. On analysis, it is
obtained that the fast pipelined CORDIC architecture drastically increases area and power by increasing number
of iterations and number of cells usage. Thus the algorithm is greatly enhanced in future use. This design can
also be implemented in FPGA or ASIC to achieve the spectral efficiency in OFDM WLAN reciever. The
minimization of the power difference or maximizing the SINR approaches could be considered to optimize the
compensation process such that the system performance is improved. From the architectural point of view where
the iterative process adds more challenge to the design of the synchronization unit. Furthermore, the timing and
frequency synchronization architecture unit could be evaluated in a testbed OFDM system.
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