In other research , two new Nyquist pulses were proposed using parametric linear combination pulse (PLCP) and linear combination pulse (LCP) methods, respectively. However, another study showed that the error performance of BTN is not superior to that of RC at all signal-to-noise ratios (SNRs) several other studies have shown that the RC side lobe spectra have a 15 dB gain over BTN. The so-called ‘better than Nyquist’ (BTN) pulse reported in another study outperforms RC in terms of a larger eye pattern opening and lower error rate. Other studies achieved a gain in terms of the error performance and IR tail behaviour but at a considerable expense of spectrum characteristics such as stopband attenuation and transition bandwidth. The PHYDYAS filter was proposed to be used in a filter bank multicarrier system because of its good characteristics in both the time and frequency domains. Previous studies have recorded a trivial improvement over RC and RRC in terms of spectrum behaviour. Varieties of pulses have been proposed to improve the performance of the RC and RRC pulses. The 3G Partnership Project has used the RC and RRC pulses . The most common Nyquist pulses are the raised cosine (RC) pulse and its counterpart, the root-raised cosine (RRC) pulse . Therefore, the tradeoff between the time and frequency domain parameters is prevalent and related to application demands. However, designing an NF that considers all the conditions is very restrictive and challenging because a signal cannot have a concentration on both the time and frequency domains concurrently . (v) Flat frequency response in the passband and more-constrained energy in the spectrum of interest . (iv) Amplitude frequency response with fast roll-off and highly attenuated stopband to overcome the sensitivity to frequency offset and mitigate the intercarrier interference . (iii) Real and even function and no overshoot filter IR with a linear phase are demanded . (ii) A shorter and lower level of the IR tail to reduce the peak-to-average power ratio (PAPR) of the transmit signal . (i) A low-level and rapidly decaying tail of the filter impulse response (IR) to provide immunity against timing jitter, minimise the ISI , and improve the error performance . The studies in the literature report that the following are the considerations for filter design Free inter-symbol interference (ISI), which is addressed by a Nyquist filter (NF) , is required in pulse shapes to combat channel distortion . The research trends to design a new waveform for a 5G air interface highly depend on a filter to reshape the transmit signal , although to design a new pulse shaping filter is a substantial challenge.ĭesigning a pair of matched filters whose combination (cascade) is a Nyquist pulse shape is a classical problem , and, recently, it was suggested as a candidate pulse-shaping method for 5G . Hence, the conventional OFDM is not appropriate for the fifth-generation (5G) mobile communication systems. The transmit signals of orthogonal frequency division multiplexing (OFDM), which is the dominant technology for broadband wireless and wired communications, exhibit high out-of-band emission (OOBE) as a result of the rectangular transmit pulse: the signals have high spectral side lobes. The reduction in the out-of-band emission makes the proposed filter an efficient candidate for future filter bank multicarrier scheme. The results for the proposed filters portray good interference confinement either in time or frequency axis. The intrinsic interference was examined by determining the autocorrelation and cross-correlation coefficients of the prototype filters in the frequency-time grid. The error rates are evaluated over a noisy channel, and the new pulses offered better performance than PHYDYAS and RRC. The results demonstrate an improvement in the eye pattern, impulse response, and spectrum behaviours. Four Nyquist pulse shapes are introduced, examined in terms of time and frequency characteristics, and compared with those of the two most popular pulses in the literature: root-raised cosine (RRC) and PHYDYAS. Introducing two-time parameters in the filter function provides more degrees of freedom and high flexibility to shape different Nyquist pulses. In this study, the authors propose a novel Nyquist filter based on the convolution of a rectangular and a truncated sinc pulses. IET Generation, Transmission & Distributionĭesigning a new pulse-shaping filter that satisfies the Nyquist condition to mitigate inter-symbol interference and achieve better stopband attenuation is a new step towards the development of next-generation mobile communication systems.IET Electrical Systems in Transportation.IET Cyber-Physical Systems: Theory & Applications.IET Collaborative Intelligent Manufacturing.
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