Direct vs. Two-Step Approach for Unique Word Generation in UW-OFDM

TL;DR

This paper compares the direct and two-step methods for generating unique word OFDM symbols, analyzing their differences in symbol construction, system performance, and bit error ratio through analytical proofs and simulations.

Contribution

It provides a detailed analytical and simulation-based comparison of the direct and two-step approaches for unique word OFDM symbol generation, highlighting their differences.

Findings

The two approaches produce fundamentally different OFDM symbols.

System bit error ratios differ significantly between the two methods.

Analytical proofs confirm the distinct characteristics of each approach.

Abstract

Unique word OFDM is a novel technique for constructing OFDM symbols, that has many advantages over cyclic prefix OFDM. In this paper we investigate two different approaches for the generation of an OFDM symbol containing a unique word in its time domain representation. The two-step and the direct approach seem very similar at first sight, but actually produce completely different OFDM symbols. Also the overall system's bit error ratio differs significantly for the two approaches. We will prove these propositions analytically, and we will give simulation results for further illustration.