4-ary 스케일링 웨이브릿 편이 변조 시스템의 성능 분석에 관한 연구

To compare the transmission system suitability for power-line communications the spectral efficiency and the required transmission power are two important fundamental factors. In this paper these two factors are studied for our proposed MMFSK (M-ary multilevel FSK) system. Spectral efficiency eta of MMFSK system is a function of number of frequency levels n, number of time chips L, number of hopping patterns h. An equation connecting eta and n, L, h is derived and quantitative relationships between these parameters are studied. As a comparison spectral efficiency of existing systems such as OFDM, MFSK, multilevel FSK are also shown. Results show that compared to ordinary OFDM systems one tenth of spectral efficiency can be achieved by the proposed system which may not be attained by the other systems. The required transmission power for a fixed error rate directly relates to the radiation power. To obtain the required transmission power, relation between error rates and signal to noise ratio should be clarified. Transmission feature between the output of the transmitter and the input of the receiver for MMFSK is same as that for MFSK and the symbol error probability at the receiver input is same. Difference in bit error rate comes from difference of symbol to bit transformation process. A consideration on the relation between bit error probability and symbol error probability in MMFSK is given and a formula representing worst case probability of bit error is derived. A comparison between the worst case bit error probability and the bit error probability obtained by a simulation is shown. Using these results it is cleared that the radiation power of MMFSK is 20~50 times smaller than that of OFDM.

This paper presents the estimation of bit error ratio (BER) from error vector magnitude (EVM) for the quadrature phase shift keying (QPSK) modulation format with the Viterbi & Viterbi algorithm and differential decoding to compensate for laser phase noise. It is demonstrated analytically and through simulation that a calibration is necessary when using the established relationship between EVM and BER to take into account the implementation penalty associated with the carrier phase recovery algorithm. Simulation results using the proposed calibration technique are presented for different combined linewidth symbol duration product in a QPSK coherent system. The impact on the number of symbols used to estimate the BER from EVM analysis is also investigated and compared to error counting. An estimation with lower uncertainty is demonstrated to be achievable with EVM analysis compared to error counting for different number of symbols. Finally, the estimation of BER for a 16-ary quadrature amplitude modulation (16- QAM) optical coherent system is investigated using the blind phase search algorithm for carrier phase recovery.

Estimations of the probabilities of bit errors in a fast-hopped M-ary-frequency-shift-keyed (MFSK) signal can be obtained by specifying a range of scenarios and an exhaustive set of for which the occurrence or non-occurrence of symbol errors can be determined. The probability of symbol error for a given scenario is computed as the sum of the probabilities of occurrence of those subscenarios that produce symbol errors. An error is assumed to occur when the channel output of a most-often-jammed channel exceeds that of the channel containing the signal. An efficient method is presented for computing the probabilities of each possible subscenario. In the important case that there is only one jamming tone in the frequency band of a jammed hop, a partitioning technique enables precise calculations of these probabilities even when the number of hops combined is quite large. Monte Carlo techniques plus precise calculations in special cases are used to calculate the probabilities when the number of jamming tones per jammed hop is greater than one. >

Non-orthogonal multiple access (NOMA) has been gaining notable attention in the context of next generation communication system. The key primary benefit includes the higher spectrum efficiency compared to its various orthogonal counterparts. In this treatise, we consider a power NOMA design based on the minimum bit error ratio (MBER) criterion. Inspiration has been drawn from the MBER based works, which show a considerable performance improvement in terms of bit error ratio (BER) for a system. In this work, we have considered a single-input single-output (SISO) system with quadrature phase shift keying (QPSK) signal constellation. The numerical results demonstrate an overall BER improvement compared to the existing schemes, albeit, the scheme attracts large computational complexity. Traditionally, NOMA increases the spectral efficiency compared to its orthogonal counterpart. Nevertheless, our proposed solution will still hold this feature along with a better BER performance, though its spectral efficiency will be less compared to the traditional sum-rate based power NOMA.

Due to the increase in massive device connectivity and increasing demands of future technologies, the Fifth-Generation (5G) networks are expected to support high spectral efficiency and low latency. In this regard, Non-Orthogonal Multiple Access (NOMA) technique has grabbed drastic attention from researchers and industry. Furthermore, to improve the performance of the NOMA system, we have incorporated the idea of cooperative communication. This paper considers a downlink NOMA system consisting of a Base Station (BS), two relays named R1 and R2, employed with Decode and Forward (DF) protocol, one far user, and one near user. In this work, an algorithm to investigate the Symbol Error Probability (SEP) performance of cooperative downlink NOMA system with Quadrature Phase Shift Keying (QPSK) modulation in the presence of the Rayleigh channel fading environment is developed. From the simulation results, it is observed that the SEP performance of the proposed NOMA system is significantly enhanced compared to that of the existing downlink NOMA system due to cooperation from the relay nodes. In addition to that, the SEP performance analysis has been made by varying the distance between the relays and BS resulting in increased SNR and reduced SEP.

This paper presents a versatile approach to implement BPSK (Binary Phase Shift Keying), QPSK (Quadrature Phase Shift Keying), FSK (Frequency Shift Keying), QFSK (Quadrature Frequency Shift Keying), M-PSK (M-ary Phase Shift Keying) and M-FSK (M-ary Frequency Shift Keying) on a Zynq 7000 All Programmable SoC which can find application in SDR (Software Defined Radio). The designs are implemented using Verilog HDL (Hardware Description Language) and the tool used is Vivado IDE (Integrated Development Environment) 2017.4 by Xilinx. The system follows a modular approach to make the design easy to modify and reuse. The design approach followed is a top-down portraying the primary modules and then moving into details of each module implementation. The Sine wave is generated using a look-up-table and the phase or frequency values of the sine wave produced is dependent upon the modulating message bits. With symbol sample frequency selection input the design is able to switch the rate at which the input message symbols are sampled facilitating the design to switch between message symbol sampling rate on the fly. These features of the design can find potential applications in SDR (Software Defined Radio).

We first demonstrate delta-sigma digitization and coherent transmission of data over cable system interface specification (DOCSIS) 3.1 signals in a hybrid fiber coax (HFC) network. Twenty 192-MHz DOCSIS 3.1 channels with modulation up to 16384QAM are digitized by a low-pass cascade resonator feedback (CRFB) delta-sigma analog-to-digital converter (ADC) and transmitted over 80-km fiber using coherent single-λ 128-Gb/s dual-polarization (DP) quadrature phase-shift keying (QPSK) and 256-Gb/s DP-16QAM optical links. Both one-bit and two-bit delta-sigma digitization are implemented and supported by the QPSK and 16QAM coherent transmission systems, respectively. To facilitate its practical application in access networks, the coherent system is built using a low-cost narrow-band optical modulator and RF amplifiers. Modulation error ratio (MER) larger than 50 dB is successfully demonstrated for all 20 DOCSIS 3.1 channels, and high-order modulation up to 16384QAM is delivered over fiber for the first time in HFC networks. The raw DOCSIS data capacity is 54 Gb/s with net user information ~45 Gb/s. Moreover, the bit error ratio (BER) tolerance is evaluated by measuring the MER performance as BER increases. Negligible MER degradation is observed for BER up to 1.5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-6</sup> and 1.7 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> for one-bit and two-bit digitization, respectively.

The performance of cellular digital mobile radio systems is investigated using quadrature amplitude modulation (4-QAM) and differential phase shift keying (DPSK) in a frequency nonselective Rayleigh fading environment with lognormal shadowing, including the effects of (white) Gaussian noise, narrow-band impulsive noise/interference (Middleton's Class A model), and cochannel interference. The performance is analyzed in terms of probability of bit error. The UHF groundwave propagation law is introduced by considering the local mean power to be inversely proportional to the fourth power of propagation distance. To investigate the improvement in performance the influence of selection diversity and maximal ratio combining on the bit error probability is analyzed. It has been found that shadowing significantly affects the bit error performance. Application of selection diversity or maximal ratio combining results in important improvement of system performance. Selection diversity gives better results than maximal ratio combining for low signal-to-noise ratios. Results of our analysis show maximal ratio combining is not that sensitive to unequal branch signal-to-noise-plus-interference ratio.

In this paper, we investigate the impact of the transmitter finite extinction ratio and the receiver carrier recovery phase offset on the error performance of two optically preamplified hybrid M-ary pulse position modulation (PPM) systems with coherent detection. The first system, referred to as PB-mPPM, combines polarization division multiplexing (PDM) with binary phase-shift keying and M-ary PPM, and the other system, referred to as PQ-mPPM, combines PDM with quadrature phase-shift keying and M-ary PPM. We provide new expressions for the probability of bit error for PB-mPPM and PQ-mPPM under finite extinction ratios and phase offset. The extinction ratio study indicates that the coherent systems PB-mPPM and PQ-mPPM outperform the direct-detection ones. It also shows that at $$P_b=10^{-9}$$Pb=10-9 PB-mPPM has a slight advantage over PQ-mPPM. For example, for a symbol size $$M=16$$M=16 and extinction ratio $$r=30$$r=30 dB, PB-mPPM requires 0.6 dB less SNR per bit than PQ-mPPM to achieve $$P_b=10^{-9}$$Pb=10-9. This investigation demonstrates that PB-mPPM is less complex and less sensitive to the variations of the offset angle $$\theta $$? than PQ-mPPM. For instance, for $$M=16$$M=16, $$r=30$$r=30 dB, and $$\theta =10^{\circ }$$?=10? PB-mPPM requires 1.6 dB less than PQ-mPPM to achieve $$P_b=10^{-9}$$Pb=10-9. However, PB-mPPM enhanced robustness to phase offset comes at the expense of a reduced bandwidth efficiency when compared to PQ-mPPM. For example, for $$M=2$$M=2 its bandwidth efficiency is 60 % that of PQ-mPPM and $$\approx 86\,\%$$?86% for $$M=1024$$M=1024. For these reasons, PB-mPPM can be considered a reasonable design trade-off for M-ary PPM systems.

In super-Nyquist wavelength division multiplexed (WDM) systems with frequency spacing smaller than the signal baudrate, the maximum-likelihood (ML) decoder in the receiver is usually introduced to compensate for intersymbol interference due to tight spectral filtering, such as polybinary shaping. After the ML decoder, symbol errors tend to propagate, causing excess continuous errors. Considering that forward error correction (FEC) is commonly introduced, the excess continuous errors degrade bit-error ratio (BER) performance after FEC, so-called post-FEC BER. In order to suppress the performance degradation, we introduce iterative decoding between the first ML decoder for polybinary shaping and the second FEC decoder in the receiver. First, we calculate BER characteristics of polybinary-shaped super-Nyquist WDM quadrature phase-shift keying (QPSK) signals. The results show that iterative decoding is effective for improving post-FEC BER performance. A lager pre-FEC BER threshold for post-FEC BER <; 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> is obtained in super-Nyquist WDM case than in the Nyquist WDM case, although a higher signal-to-noise ratio (SNR) is required. Next, we measure the BER characteristics of three-channel duobinary-shaped super-Nyquist WDM 12.5-Gbaud dual-polarization QPSK signals. The iterative decoding reduces the optical SNR penalty by 0.8 dB. A larger pre-FEC BER threshold of 3.1 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> is obtained in the duobinary-shaped super-Nyquist WDM case, compared with the threshold of 2.2 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-2</sup> in the Nyquist WDM case.

An efficient network is critical to support the rapid growth in traffic on mobile networks, since current network PCS1900 (2G) cannot support such a huge demand. The objective of the third-generation (3G) UMTS (Universal Mobile Telecommunication System) of wireless communication is to provide high speed wireless communication to support multimedia, large data, and video. However, the co-existence of the two mobile radio systems (PCS1900 and UMTS) which share the same frequency band leads to a major issue. A serious issue of co-existence occurs when the downlink of the system is closer to the frequency bands of the concerned system. The PCS-1900 downlink band (1,930-1,990) and WCDMA (UMTS) uplink band (1,920-1,980) widely overlap, which causes interference between UMTS mobile unit and PCS-1900 base station. Therefore the objectives of this paper is to study the effect from PCS 1900 base station interference on UMTS mobile unit performance in terms of the probability of bit error by developing the Probability of bit error equation of DSS-QPSK from the existing Probability of bit error equation. This paper also evaluates the degradation of UMTS mobile unit performance in terms of probability of bit error when the system is interfered by PCS1900 base station.

Non-binary forward error correction (FEC) coding in conjunction with M-ary hyper phase-shift keying (MHPSK) is considered in order to improve the robustness of a satellite communications uplink. MHPSK is a spectrally efficient modulation technique that uses four orthonormal basis functions to increase the distance between different symbols in the signal space. Spectral efficiency and probability of bit error are two key figures of merit used to evaluate digital modulation techniques. The use of four orthonormal basis functions provides an advantage over traditional modulation techniques such as M-ary phase-shift keying (MPSK) and M-ary quadrature amplitude keying (MQAM) that only possess two degrees of freedom. MHPSK offers an improvement in bit error performance over other spectrally efficient modulation techniques for the same average energy per bit-to-noise power spectral density ratio and similar spectral efficiency. As a result, MHPSK offers a novel way to improve both throughput and reduce power requirements using easy to generate waveforms. In this paper, Reed Solomon coded symbols are assumed to be transmitted with MHPSK. MHPSK, MPSK, and MQAM are compared in terms of probability of bit error and bandwidth efficiency, where the number of bits per coded symbol are typically designed to match the number of bits per channel symbol.

New expressions for the average probability of packet error in case of intermediate Nakagami (1960) fading channels are derived. The correlation among bits within the packet is assumed to obey the first order Markovian process. Both non-coherent frequency shift keying (NCFSK) and quadrature phase shift keying (QPSK) modulation schemes are addressed. The average probability of packet error is used to obtain an expression for the modified throughput for the non-persistent carrier sense multiple access (NPCSMA) protocol. The different fading parameters affecting the modified throughput expression such as the average signal to noise ratio (SNR), fading margin and correlation factor among bits of the same packet are also analyzed.

We analyze the end-to-end error performance of Mary frequency shift keying (MFSK) with noncoherent detection over independent and non-identical flat Nakagami-m fading channels. A dual-hop relay transmission using amplify-and-forward (AF) protocol with average power scaling (APS) mechanism [1] is considered. Generalized closed-form expressions for the average symbol error probability (ASEP) of noncoherent MFSK has been obtained following the cumulative distribution function (CDF) approach. Moreover, we derive a simplified closed-form expression for the ASEP over high signal-to-noise ratio (SNR) over the source-relay link. Computer simulations are performed to validate our proposed mathematical analysis. The obtained error probability expressions will help the design of two-hop relay networks adopting MFSK in determining various system parameters such as the transmission power at the source and the gain factor at the relay.

The authors analyze incoherent detection of trellis-coded continuous-phase M-ary FSK, using M quadrature receivers and trellis decoding. The upper bounds on the bit error rate as well as the 99% energy bandwidths are given for the codes under consideration. In particular, the authors consider trellis codes with rates of 1/2 and 2/3 with symmetric and asymmetric signal constellations. The upper bounds on the probability of error are obtained for symmetric and optimum asymmetric signal constellations. The optimum asymmetry is one which minimizes the probability of bit error. The performance of this system is compared with that of standard continuous-phase modulation techniques (MSK, duobinary, and TFM) using noncoherent detection. >