Simple OFDM

نویسندگان

  • Andrew Marcum
  • Todor Cooklev
  • Carlos Pomalaza-Raez
چکیده

There is a significant demand for a decrease in the size, weight and power (SWaP) associated with wireless systems. In this research, a low-complexity MIMO OFDM system is advanced. The proposed system is essentially multiplierless and thus requires much simpler digital hardware to be implemented. As a result, the chip area associated with the MIMO OFDM system can be significantly reduced. The reduction in complexity is obtained via modification to the Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (IFFT) algorithms necessary to implement OFDM multi-carrier modulation. Computational complexity is reduced by quantizing what are known as the “twiddle factors” in traditional FFT algorithms such as the Radix-4. The quantization allows for all multiplications to be done with values of one, negative one, zero or a value that is a power of two. Replacing standard multiplications with trivial multiplications significantly reduces the computational complexity and allows for a simple hardware implementation. Depending on the application, different quantization levels can be utilized in order to obtain the necessary performance characteristics. As more quantization levels are used, the system performance increasingly approaches the performance of a system that uses the conventional transforms.

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تاریخ انتشار 2017