Taking into consideration that f 0 is the only known a priori information, in this section, we will introduce a MMSE estimator for determination of the finite bandwidth signals a n, and then, we develop our estimator to detect the presence of the UWB signal and extract the target's range and velocity.
b m w N f s is minimum bandwidth of a user and b m i N f s is minimum bandwidth interval between two adjacent users.
It is worth mentioning that the time-dilated CIRs with bandwidth of B n can be obtained by averaging the temporal output of a SC received within the time of L/(f c′n).
B is the bandwidth of a single resource block and N 0 is the Gauss white noise.
Furthermore, we would like to point out that we can treat the interference of n UEs with each 1 PRB using the SC-FDMA transmission scheme as the same as interference from 1 UE with a bandwidth of n PRBs using the OFDMA transmission scheme as in both cases the receive power probability density function (PDF) over time will be similar.
Fig. 2 a d Magnitude frequency spectrum, power delay profile of the CIR calculated by using the low-pass-filtered signals with the bandwidth of B n, n=1 and 7, respectively.
In the experiment, QAM-based DMT signals were employed, which consisted of N subcarriers within the bandwidth of B (N = 64, B = 50 MHz, and N = 128, B = 80 MHz for two cases, respectively, which will be presented in the following section).
Active subbands allocated to the PUs and OFDM subcarriers of the SUs have been shown in Figure 1, where, the bandwidth of subband n is denoted by B n, which is allocated to PU n, and Δf is the subcarrier spacing of the CR system.
The N obtained represents that when we reserve bandwidth of N * BW, the expected value of satisfaction within Zone would be larger than or equal to user parameter S_TH.
