Single Carrier FDMA: A New Air Interface for Long Term Evolution

8

Simulation of a SC-FDMA System Using MATLAB^®

8.1 Introduction

In this chapter, we illustrate a simple yet insightful link level simulation method for SC-FDMA systems. Section 8.2 will focus on simulating the single carrier with a frequency domain equalization (SC/FDE) system and Section 8.3 on simulating an SC-FDMA system.

For the multipath channel, we consider ITU Pedestrian A and ITU Vehicular A channels [1] with additive white Gaussian noise (AWGN). The delay profiles of the two channels are described in Table 8.1.

As you can see from Table 8.1, the Pedestrian A channel has relatively short channel delay whereas the Vehicular A channel has much longer delay. Consequently, the Vehicular A channel has much more severe frequency selectivity in the frequency domain, which is illustrated in Figure 8.1.

Table 8.2 summarizes the simulation assumptions and parameters that were used throughout this chapter. Since the system sampling rate is set to 5 mega-samples per second, the channel delay was quantized to the nearest multiples of 200 nsec (= 1/(5 × 10⁶)). Also, the length of the cyclic prefix (CP) is chosen as 4 μs (20 samples) considering the maximum channel delay of the Vehicular A channel, which is 2.51 μs.

8.2 Link Level Simulation of SC/FDE

Figures 8.2 and 8.3 show the flow of the link level simulations for SC/FDE and OFDM, respectively. As mentioned in Chapter 2, we can see the similarity between the two systems; they both use the same signal processing blocks. The Matlab ...