Simple Primary User Signal Area Estimation for Spectrum Measurement

Abstract

This paper investigates a signal area (SA) estimation method for wideband and long time duration spectrum measurements for dynamic spectrum access. SA denotes the area (in time/frequency domain) occupied by the primary user's signal. The traditional approach, which utilizes only Fourier transform (FT) and energy detector (ED) for SA estimation, can achieve low complexity, but its estimation performance is not very high. Against this issue, we apply post-processing to improve the performance of the FT-based ED. Our proposed method, simple SA (S-SA) estimation, exploits the correlation of the spectrum states among the neighboring tiles and the fact that SA typically has a rectangular shape to estimate SA with high accuracy and relatively low complexity compared to a conventional method, contour tracing SA (CT-SA) estimation. Numerical results will show that the S-SA estimation method can achieve better detection performance. The SA estimation and processing can reduce the number of bits needed to store/transmit the observed information compared to the FT-based ED. Thus, in addition to improved detection performance it also compresses the data.

Smart Spectrum for Future Wireless World

“…To resolve this issue, we also proposed a false alarm cancellation (FC) technique. We showed that, based on numerical evaluations, our proposal, simple signal area estimation with false alarm cancellation (S-SA+FC), has advantages in terms of not only detection performance, but also computational cost [35]. The advantage of the detection performance of S-SA+FC is visualized in Fig.…”

“…In comparison with ED, S-SA+FC can achieve more than a 4 dB gain in SNR. In addition, a comparison in terms of computational cost showed that S-SA-based signal area estimation can achieve the lowest computational cost [35]. This investigation addressed the issues of accuracy and computational cost.…”

“…The entire process consists of three parts: Welch FFT-based power spectrum estimation [36]- [38], ED with noise power estimation [25], and simple signal area estimation [35], as shown in Fig. 2.…”

“…2. An investigation of signal area estimation as post-processing was reported in [35]. The outputs of FFT-based ED are shown in Fig.…”

“…In [35], a simple signal area (S-SA) estimation method, which consists of two estimations, width and height, as shown in Fig. 4(b), was presented.…”