A versatile high speed bit error rate testing scheme

The increasing demand for high-density and high-speed digital optical recording systems has made the development of advanced coding and signal processing techniques for fast and reliable data recovery increasingly important. In recent years, the parity-check (PC)-code-based reception technique has been widely studied for magnetic recording systems, and it is projected to be highly promising for high-density optical recording. The PC code is an inner error correction code (ECC), which can detect dominant short error events of the system, using only a few parity bits. This reduces the loss in error correction capability of the outer ECC due to random short errors and results in a simple and efficient solution to improve the overall performance. This thesis is dedicated to the design and analysis of PCcode- based recording systems to achieve higher recording capacity with low implementation complexity, for high-density blue laser disc systems. In particular, most of the key components of the PC-code-based optical recording system have been designed and optimized for different recording densities, and different proportions of white noise and media noise. During the development of advanced coding and detection techniques, it becomes necessary to investigate the system’s performance with different coding schemes and recording densities. In Chapter 2 of the thesis, we propose a generalized Braat-Hopkins model for optical recording channels, which provides a fair basis for the performance comparison of detection schemes over different coding schemes and recording densities, for channels with additive, white Gaussian noise (AWGN) and media noise. Various basic issues associated with the PC-code-based systems are investigated in Chapter 3. These include bounds for bit error rates and error event probabilities, the dominant error events at channel detector output, different PC codes, simple and efficient post-processors, the impact of error events that are split across data block boundaries and the corresponding remedy, as well as the effects of code rates and recording densities. Simulation results show that a 4-bit PC code achieves the best performance. The corresponding bit error rates (BERs) are very close to the performance bounds, at both nominal and high densities. Constrained codes, which serve as a key component in the read-write channel of data storage systems, are desired to have a high code rate with low-complexity encoder/decoder. In Chapter 4, we investigate the design of certain capacity-approaching constrained codes for optical recording systems. In particular, we derive analytically the relationship between the number of encoder states and the maximum size of these codes. We identify the minimum number of encoder states that maximizes the code rate, for any desired codeword length. The design of constrained PC codes is key to the development of PCcode- based systems, and the systematic design of efficient constrained PC codes remains a challenging problem. In Chapter 5, we propose a general and systematic code design technique for constructing capacity-approaching constrained PC codes, which can detect any type of error events of the system, with the minimum code rate loss. Compared to the rate 2/3 code without parity, the newly designed constrained 4-bit PC code achieves a performance gain of 2 dB at nominal density, and 1.5 dB at high density, at BER = 10-5. As the dominant noise for high-density optical recording systems, media noise severely degrades the performance of channel detectors and postprocessors that are designed for AWGN. In Chapter 6, we propose two novel modifications to the bit detector to combat media noise. We further develop a data-dependent post-processing scheme for error correction. Compared to the system designed without considering media noise and without PC codes, the overall performance gain of the developed scheme can be more than 11 dB at high media noise levels. In data storage systems, the ECC failure rate (EFR) serves as the ultimate measure of the data recovery performance. In Chapter 7, we develop semi-analytical approaches for estimating the EFR, and analyze EFRs for the developed PC-code-based systems, for the cases without and with interleaving. Our analysis shows that with the optimum interleaving degrees, compared to the rate 9/13 code without parity, the 2-bit PC code achieves a gain of around 0.5 dB, and the 4-bit PC code gains 0.6 dB, at high record ing density and EFR = 10-16. The thesis concludes in Chapter 8 with some suggestions for further work.

This rsearch work presents an educational software interface tool for analyzing and estimating the bit error rate (BER) of an optical communication system. Currently BER estimation tool required expensive measurement equipment such as serial data analyzer (SDA) and BER Tester. In addition to cost all this equipment is also limited to BER estimation based on standard format and is not suitable for custom analysis because of time constraint to use equipment even during offline estimation. This educational software interface tool is developed using OPTISYSTEM software and built-in MATLAB command. MATLAB GUI is used as the software tool because it’s friendly user. OPTISYSTEM is used to design the PAM two levels, four levels, and eight levels system. MATLAB is used as an interface to build the BER estimation tool for measuring the PAM multilevel modulation technique. The MATLAB GUI system for measuring BER is design using Gaussian probability errors approximation method. The designed BER estimation tool simulation, is able to plot the eye diagram, BER diagram, Q-factor value, threshold value, and the most important function is to analysis the BER value for two levels, four levels and eight levels of a PAM optical communication systems.

In this paper, we propose a novel peak to average power ratio (PAPR) reduction scheme of orthogonal frequency division multiplexing (OFDM) signals. In our proposed scheme we exploit the repeated rotation and recombination of the in-phase and the quadrature components of an OFDM symbol in time domain. Our proposed scheme has two main advantages over the previously known scheme such as iterative partial transmit sequence (I-PTS), which are 1) remarkably lower computational complexity and 2) less required side information overhead than the I-PTS scheme. Based on our derived complementary cumulative distribution (CCDF) of PAPR, we show that our proposed scheme gives only 0.2 - 0.3 dB loss compared to the I-PTS scheme in terms of PAPR threshold while the complexity for the implementation is much reduced. Furthermore, the proposed scheme does not cause any loss of bit error rate performance over both the additive white Gaussian noise (AWGN) channel and the frequency selective channel even though the simulation results regarding the bit error rate (BER) performance is not shown in this paper due to the limited space of the pages.

The effects of multipath fading and additive white Gaussian noise (AWGN) on the bit error rate (BER) performance of direct-sequence code-division multiple-access (DS-CDMA) systems is studied in this paper. The expression for the conditional BER, conditioned on a given level of fading is derived and then the unconditional BER is evaluated. The BER performance results of the system are evaluated in a fading channel for different magnitude of fading. The proposed approach is also extended to estimate the BER performance of the CDMA system having multiple receiving antennas. The effectiveness of the selection method and maximal ratio combining (MRC) method as diversity combining schemes are investigated and compared. To enhance the system performance channel coding is also applied to the system.

A simple and intuitive new expression for the bit error rate (BER) performance of a synchronous jointly optimum receiver is derived. The receiver is used to detect a binary phase-shift keying (BPSK) signal in the presence of an identical cochannel interferer and additive white Gaussian noise (AWGN). The new expression separates into the BER of BPSK in AWGN plus a term due to the interference. The term due to interference approaches zero when the interference power or its correlation with the desired signal tends to zero, as expected.

Hierarchical constellations offer a different degree of protection to the transmitted messages according to their relative importance. As such they found interesting application in digital video broadcasting systems as well as wireless multimedia services. Although a great deal of attention has been devoted in the literature to the study of the bit error rate (BER) performance of uniform phase shift keyed (PSK) constellations, very few results were published on the BER performance of hierarchical PSK constellations. We obtain exact and generic expressions in M for the BER of the generalized hierarchical M-PSK constellations over additive white Gaussian noise (AWGN) and fading channels. For the AWGN case, these expressions are in the form of a weighted sum of Pawula (1982) F-functions and are solely dependent on the constellation size M, the carrier-to-noise ratio, and a constellation parameter which controls the relative message importance. Because of their generic nature, these new expressions readily allow numerical evaluation for various cases of practical interest.

Wavelet transform-based methodologies for both Automatic Modulation Recognition (AMR) and Demodulation of digitally modulated communications signals can be utilized in an enabling platform for the implementation of a new class of communications systems. In particular, such techniques could enable the development of agile radio transceivers for use in both commercial and military applications. Such radio transceivers would have the ability to transmit and receive signals using many different modulation schemes while employing a common receiver architecture based on a single demodulator. In this dissertation, the development of AMR and Demodulation techniques are based on the relatively new mathematical theory of Wavelet Transforms (WTs). Information-bearing signals acquired by communications receivers are transformed into the wavelet-domain using the Continuous Wavelet Transform (CWT) and then applied to signal processing algorithms that also use the CWT in conjunction with pattern recognition techniques. In particular, the method of template-matching is used for both the AMR and Demodulation processes. Signal templates characterizing various modulated signals are used for both processes. The signal templates are determined based on the signal features present in the fractal patterns of their corresponding scalograms for specific modulation schemes as they appear in the wavelet-domain. The algorithms developed in this work are capable of both classifying the method of modulation used in the acquired signal, as well as subsequently automatically demodulating the signal to recover the message. The classes of digitally modulated signals considered in this work include variants of the Amplitude-, Frequency-, Phase-Shift Keying modulation families, i.e., ASK, FSK, and PSK, respectively, and multiple-level Quadrature Amplitude Modulation (M-ary QAM) families. The AMR and Demodulation performances are evaluated in the presence of Additive White Gaussian Noise (AWGN) over a wide range of Signal-to-Noise Ratio (SNR) values. Through extensive Monte Carlo computer simulations it is determined that the average correct classification rates using wavelet-based AMR for PSK, ASK, and QAM are over 98%, and over 90% for FSK signals, all at an SNR of 0 dB. The Bit Error Rate (BER) performance obtained using wavelet-based Demodulation is at least one order of magnitude better than the matched filter-based BER performance realized for the modulation schemes considered.

Wireless Digital Laser Communication Link (WDLCL) is an emerging technology and alternate to the conventional RF / Fiber link with numerous advantages / applications. The data link quality can be best estimated by measuring the Bit Error Rate (BER) in WDLCL. Since the characteristics of WDLCL severely affected by the atmosphere, an experimental based study about the turbulence medium becomes significant. In this paper, the complete theoretical concepts related to the challenges of WDLCL are listed. The Opto-electronic architecture (Tx and Rx) developed in this research is detailed with the necessary photographs. The core design of the low-cost BER Tester (BERT) is developed in the reconfigurable Field Programmable Gate Array (FPGA) is explained. The BER is measured in various atmospheric conditions for different beam radius and link distance and the observations are reported. Over a long period of time, real-time experimental data was continuously collected and the results were analyzed. Beam scintillation, spreading and wandering were accounted as the atmospheric turbulent effects on the laser beam with beam steering system. The experimental results reveal that atmospheric turbulence has a significant impact on the BER.

The WiMax (Worldwide Interoperability for Microwave Access) is a technology in<strong> </strong>broadband wireless access, which employs OFDM (Orthogonal Frequency Division Multiplexing) as an alternative transmission to enable high speed data in communication system. This research aim is to analyze the performance system of the OFDM-Based WiMAX, which used the cyclic prefix. The model was designed in four schemes of simulation method, the BPSK (Binary Phase Shift Keying, QPSK (Quadrature Phase Shift Keying), 16 QAM (Quadrature Amplitude Modulation) and 64 QAM. Each scheme was investigated BER (Bit Error Rate) on AWGN (Additive White Gaussian Noise) channel and multipath Rayleigh fading channel, which had applied the cyclic prefix. By simulation of the cyclic prefix was produced the modulation measurement of the BPSK, QPSK, 16 and 64 QAM. The performance result of Eb/No 15 dB was obtained the BER of BPSK and QPSK of 1.11E-11, the BER of 16 QAM and 64 QAM of 8.69E-06 and 0.00333 respectively. Those results indicated much smaller BER value than EbNo 0 dB which BPSK and QPSK of 1 BER, 1.5 and 1.75 BER for 16 QAM and 64 QAM respectively. In conclusion, a higher value of EbNo, hence the BER value would be lower.

In this paper, we derive new generalized expressions to compute error rates for M-Ary square quadrature amplitude modulation (SQAM) in the presence of additive white Gaussian noise (AWGN). The proposed method uses a region based symbol error rate (SER) and bit error rate (BER) computation technique which reduces the bit error rate over the conventional method as the size of the constellation increases. For the constellation size of 1024, at 10 dB average bit energy to noise spectral density ratio (E b /N o ), BER is improved by a factor of 1.654, while for 256-QAM, the BER shows an improvement by a factor of 1.196.

We investigate the multiuser interference on the downlink channel (from base station to users) in cellular code-division multiple access (CDMA) and time-division multiple access (TDMA) systems. The results indicate that for the same total bandwidth occupancy and maximum number of users per cell, multiuser interference is approximately 10 dB higher in CDMA in fully-loaded cells. The implication of these results is that for the same total bandwidth and number of users per cell, TDMA gives significantly superior bit error rate (BER) performance, as confirmed by our numerical results on additive white Gaussian noise (AWGN) channels as well as on flat Rayleigh fading channels. Alternatively, CDMA needs approximately 10 times more bandwidth than TDMA to achieve the same signal-to-interference ratio (SIR) and bit error rate (BER) performance in fully loaded cells.

The Aim is to Implement RTL Design Architecture for Compatible Serial Bit Error Rate Tester SOCa Multi rate Multichannel PRBS Sequence Based SERIAL BERT IP Core for High Speed Wireless Serial Communication Data Acquisition SOC Transceiver Products a Applications (3G, 4G, GPS, GSM, CDMA, WIFI, GIFI etc). Testing of Data Done By Different PRBS Pattern Sequences-2e7-1, 2e10-1, 2e15-1, 2e23-1, 2e31-1. Basically this Serial BERT Consists of PRBS Generator Module located in the Transmitter Side a sends Pseudo Random Pulse signal is transmitted by the Serial link. Second Module is located in the receiver generate the same signal a compare with the transmitted signal, if any errors, like bit slip, bit error, Additive white Gaussian noise (AWGN), can then be detect the number of errors, and these errors are evaluated by the BERT core, estimate the error rate w.r.t number of bits. Design implementation through Soft Process Description using VHDL a Verilog HDL, Simulation a Synthesis of design done by Xilinx ISE Software Design Tool, Testing a Debugging done by FPGA Spartan Development Kit.

Non-orthogonal multiple access (NOMA) is one of the potential future mobile network methods that can give better spectral efficiency, huge connectivity, and low latency. As a result, academic and industry researchers have studied the error performances and capacity of NOMA systems. The main drawback of NOMA methods is user interference, which is generally addressed by interference cancellation techniques such as Successive Interference Cancellation (SIC) at receivers. Therefore, it is better to obtain the bit error rate (BER) performance of NOMA. Each user's power level is determined by the power level assigned to them. As a result, this work presents BER analysis for two NOMA users using BPSK modulation in additive white Gaussian noise (AWGN), Rayleigh, and Rician fading channels. Initially, we assessed BER performance for various Signal to Noise Ratio (SNR) values by assuming two users who are equally spaced from the base station (BS). Later, the BER performance for various transmit powers is assessed by assuming two users are situated at varying distances from the BS. The performances are discussed using MATLAB simulations. The comparative BER analysis is also studied for various fading environments.KeywordsBERNOMABPSKSICFading

Performance of both orthogonal frequency division multiplexing (OFDM) and single carrier (SC) systems suffers from a carrier frequency offset (CFO) due to Doppler effect and the carrier instability between the transmitter and the receiver. We investigate the bit error rate (BER) performance degradation of OFDM and SC systems due to the frequency offset in an additive white Gaussian noise (AWGN) channel as well as multipath Rayleigh fading channels. We consider three effects to the BER degradation, i.e., phase shift, useful power decrease and intercarrier interference (ICI). We also derive the approximate expressions of BER under binary phase shift keying (BPSK) and quaternary phase shift keying (QPSK) for both OFDM and SC systems in the presence of CFO. In general, SC is more robust to CFO in the AVVGN channel than OFDM in terms of BER, while both of them suffer similarly from CFO in the multipath Rayleigh fading channels assuming the the same CFO.

The bit error rate (BER) performance of digital cellular radio systems was investigated in a Nakagami (1960) fading, correlated lognormal shadowing and additive white Gaussian noise (AWGN) environment for noncoherent differential phase shift keying (DPSK) modulation. Two models were used to determine the BER; the first one is based on the cumulative power levels of cochannel interferers while the second one is based on instantaneous cochannel interference power. The relative advantages of the two models were presented for various design parameters. The effects of bit energy to noise ratio, frequency reuse distance, cluster size, correlation coefficient, shadow spread, and fading parameter were studied. The BER was observed to be lower in a correlated shadowing environment compared with the uncorrelated case. The near-far effect was studied by assuming that both the desired and interfering mobiles are randomly located in their corresponding cells.