I. INTRODUCTION
The low power impulse radio ultra-wideband (IR-UWB) can be used in wireless sensor networks (WSNs), radio-frequency identification (RFID) tags, and Internet of Things (IoT) based applications [1]–[6]. Both coherent and noncoherent UWB receivers have been proposed in the literature. Coherent UWB receivers use complex hardware circuitry and signal processing techniques as compared to noncoherent receivers [7]. Hence, coherent UWB receivers are not a viable solution for simple futuristic WSNs and IoT applications [3]. Noncoherent UWB receivers’ performance is sub-optimal, though these receivers are free from complex channel estimation and are also robust against UWB pulse shape distortions occuring during the transmission. Further, noncoherent UWB receivers’ performance is limited by the low transmitted power of UWB signals (due to FCC regulations). Therefore, noncoherent UWB receivers need higher processing gain to achieve near optimal performance at low signal-to-noise ratio (SNR).