Showing papers on "Bit error rate published in 1984"
TL;DR: In this article, a survey of various types of ARQ and hybrid ARQ schemes, and error detection using linear block codes is presented, where a properly chosen code is used for error detection, virtually error-free data transmission can be attained.
Abstract: ERROR DETECTION incorporated with automatic-repeatrequest (ARQ) is widely used for error control in data communications systems. This method of error control is simple and provides high system reliability. If a properly chosen code is used for error detection, virtually error-free data transmission can be attained. This paper surveys various types of ARQ and hybrid ARQ schemes, and error detection using linear block codes.
976 citations
TL;DR: A tutorial exposition of a number of distinct techniques in the simulation context that can be used to construct thisBER estimate, with particular reference to five specific methods which can be implemented in a simulation.
Abstract: Computer simulation is often used to estimate the bit error rate (BER) performance of digital communication systems. There are a number of distinct techniques in the simulation context that can be used to construct this estimate. A tutorial exposition of such techniques is provided, with particular reference to five specific methods which can be implemented in a simulation. These methods range from the traditional Monte Carlo trials to assumption of definite forms for the noise statistics. An attempt is made to show how these methods are related, and the specific assumptions that are invoked in order to apply them.
500 citations
TL;DR: The high-rate punctured codes of rates 2/3 through 13/14 are derived from rate 1/2 specific convolutional codes with maximal free distance based on their bit error rate performances under soft decision Viterbi decoding.
Abstract: The high-rate punctured codes of rates 2/3 through 13/14 are derived from rate 1/2 specific convolutional codes with maximal free distance. Coding gains of derived codes are compared based on their bit error rate performances under soft decision Viterbi decoding.
399 citations
TL;DR: In this article, a theory describing the effect of the FM noise on the bit error rate (BER) performance of various heterodyne and homodyne schemes was developed and the feasibility of the phase shift keying (PSK) scheme using semiconductor lasers was also discussed on the basis of analysis and experimentation.
Abstract: In coherent optical communication schemes, the FM noises of the transmitter and/or the local oscillator seriously deteriorate the receiver sensitivity. A theory is developed describing the effect of the FM noise on the bit-error rate (BER) performance of various heterodyne and homodyne schemes. To verify the theory, the BER of a phase-shift keying (PSK) heterodyne system is measured. The feasibility of the PSK scheme using semiconductor lasers is also discussed on the basis of analysis and experimentation.
203 citations
TL;DR: Results indicated that the higher number of hops per bit produced higher error probabilities as a result of increased combining losses when the square-law linear combining soft decision receiver is employed in demodulating the multihop-per-bit waveform.
Abstract: In this paper, error probability analyses are performed for a binary frequency-shift-keying (BFSK) system employing L hop/bit frequency-hopping (FH) spread-spectrum waveforms transmitted over a partial-band Gaussian noise jamming channel. The error probabilities for the L hop/bit BFSK/FH systems are obtained as the performance measure of the square-law linear combining soft decision receiver under the assumption of the worst-case partial-band jamming. The receiver in our analysis assumes no knowledge of jamming state (side information). Both exact and approximate (multiple bound-parameter Chernoff bound) solutions are obtained under two separate assumptions: with and without the system's thermal noise in the analyses. Numerical results of the error rates are graphically displayed as a function of signal-to-jamming power ratio with L and signal-to-noise ratio as parameters. All of our results, exact and approximate, indicated that the higher number of hops per bit produced higher error probabilities as a result of increased combining losses when the square-law linear combining soft decision receiver is employed in demodulating the multihop-per-bit waveform.
170 citations
TL;DR: It is shown that the most common LLSE filter design can lead to performance inferior to that of various other filter designs, but results are also presented demonstrating that an LLSEfilter design motivated by the structure of the maximum-likelihood receiver leads to consistently superior performance.
Abstract: Linear least squares estimation (LLSE) techniques can provide an effective means of suppressing narrow-band interference in direct sequence (DS) spread-spectrum systems. In the results presented here, analytical expressions for bit error rate are derived for two DS spread-spectrum systems under the conditions of either tone or narrowband Gaussian interference. It is shown that the most common LLSE filter design can lead to performance inferior to that of various other filter designs. However, results are also presented demonstrating that an LLSE filter design motivated by the structure of the maximum-likelihood receiver leads to consistently superior performance. The performance of a system using this new design criterion is compared with that of an approximation to the maximum-likelihood (ML) receiver for the tone interference model and with that of the exact ML receiver for the Gaussian interference. Finally, it is shown that the bit error rate estimate obtained from application of a Gaussian approximation for the test statistic is overly pessimistic for the systems studied here.
132 citations
TL;DR: In this article, the authors compare OOK and low-order PPM signaling formats in terms of bit error probabilities versus required signal counts per bit, and show that QPPM requires 3 dB less signal than OOK, while BPPM requires the same or slightly more than OP for the same performance.
Abstract: This correspondence compares OOK and low-order PPM signaling formats in terms of bit error probabilities versus required signal counts per bit. The results show that QPPM requires 3 dB less signal than OOK, while BPPM requires the same or slightly more than OOK for the same performance. Optimum APD gain values are from 200 to 400. When using QPPM, k_{eff} = 0.006 , and optimum gain, 60 signal counts/bit are required at 500 Mbits/s for a 10-6bit error probability.
99 citations
TL;DR: The relations between the word error probability and the decoding algorithms for block codes are reviewed and a simple approximation is derived for the information-bit error rate in terms of the channel-symbol error probability.
Abstract: The relations between the word error probability and the decoding algorithms for block codes are reviewed. A simple approximation that does not depend upon the code weight structure or the decoding details is derived for the information-bit error rate in terms of the channel-symbol error probability.
67 citations
TL;DR: Three systems are proposed for embedding data into industrial quality monochrome analog pictures by modulo masking scrambling the luminance level of only one pel in the block to offer the greater safety margin to bit errors.
Abstract: Three systems are proposed for embedding data into industrial quality monochrome analog pictures. The video signal on each scan line is sampled, and a data bit is inserted into a block of three or five pels by modulo masking scrambling the luminance level of only one pel in the block. Prior to transmission, the combined data and video sequence is converted into a continuous signal with a bandwidth that is no greater than that of the original video signal. Using six images each containing 65 536 pels, Systems 1 and 2 embedded an average of 17 430 and 8713 bits per image, while System 3 accommodated data at a constant rate of 21 760 bits/image. The data embedding procedures of Systems 1, 2, and 3 operated with average picture SNR's of 41, 44, and 30 dB, respectively, when the transmission channel was ideal. When the transmission was over a channel composed of a second-order Butterworth filter plus additive noise that yield a channel SNR of 40 dB, no bit errors occurred but System 3 offered the greater safety margin to bit errors than Systems 1 and 2.
62 citations
TL;DR: It is shown that applying this method significantly improves bit error rate (BER) performance of digital FM using discriminator detection, andoretical BER evaluation proves the superiority of this method, and establishes the optimum values for fundamental transmitter parameters.
Abstract: A new decision method for band-limited digital FM that employs discriminator detection is presented. This new method adopts a multilevel decision scheme to soften the intersymbol interference effects caused by severe band limitation. It is shown that applying this method significantly improves bit error rate (BER) performance of digital FM using discriminator detection. Theoretical BER evaluation proves the superiority of this method, and establishes the optimum values for fundamental transmitter parameters. Experimental results are provided to support the superiority of this method.
57 citations
TL;DR: Small memory codes are found which are optimized in the free-distance sense on the Gaussian channel which provide up to 4.8 dB of coding gain with 32 states over uncoded 8-PSK, a scheme having the same spectral efficiency as the codes described.
Abstract: Convolutional coding coupled with 16-PSK modulation is investigated for bandwidth efficient transmission. Rate 3/4, small memory codes are found which are optimized in the free-distance sense on the Gaussian channel. These codes provide up to 4.8 dB of coding gain with 32 states over uncoded 8-PSK, a scheme having the same spectral efficiency as the codes described. The performance is compared with earlier findings of Ungerboeck and some recent results on R = 2/3 coded 8-PSK. In addition, we present results of a channel transmission study to assess the performance of the four-state code on the band-limited nonlinear channel, and find that performance of the coded scheme degrades comparably with uncoded 8-PSK, i.e., coding gain is roughly preserved.
TL;DR: Differential detection of binary differential phase shift keyed (DPSK) signals with several impairments typical in satellite communication systems with bit error rate determined for bit timing error and frequency offset error at the receiver.
Abstract: In this paper we study differential detection of binary differential phase shift keyed (DPSK) signals with several impairments typical in satellite communication systems. In particular, the bit error rate is determined for bit timing error and frequency offset error at the receiver. The effect of a hard-limiting, band-limited repeater is also considered. The differential detector performance is determined for both conventional DPSK signals (with 0 and π phase shifts) and symmetrical DPSK signals (with - \pi/2 and + \pi/2 phase shifts). With symmetrical DPSK, adjacent bit signals are orthogonal rather than either in or out of phase. Therefore, with intersymbol interference, the error rates for all bits are equal and the average bit error rate is less with symmetrical DPSK, as shown in this paper.
TL;DR: In this paper several demodulating schemes are considered for generating the RS symbols at the relay photodetector output, and the effect of each on overall RS decoding performance is computed.
Abstract: Consideration is presently being given to an optical-RF relay deep space communication link that transmits optical PPM data from spacecraft to orbital relay, then retransmits the data via microwave to ground. It is generally advantageous to use Reed-Solomon (RS) encoding over the PPM optical link for improved error correction. In this paper several demodulating schemes are considered for generating the RS symbols at the relay photodetector output, and the effect of each on overall RS decoding performance is computed. Both Poisson and Gaussian optical noise models are used in the evaluation. The effect on performance of bit errors in the relay downlink is also examined.
TL;DR: The letter proposes a continuous ARQ scheme, to be used under high error rate conditions, that preserves the ordering of the data blocks and yields a better throughput efficiency than some known comparable schemes.
Abstract: The letter proposes a continuous ARQ scheme, to be used under high error rate conditions. The scheme preserves the ordering of the data blocks and yields a better throughput efficiency—especially for channels with large round-trip delay—than some known comparable schemes, for all block error probabilities larger than 50%.
TL;DR: It is shown that applying this method significantly improves bit error rate (BER) performance of digital FM using discriminator detection, andoretical BER evaluation proves the superiority of this method, and establishes the optimum values for fundamental transmitter parameters.
Abstract: A new decision method for band-limited digital FM that employs discriminator detection is presented. This new method adopts a multilevel decision scheme to soften the intersymbol interference effects caused by severe band limitation. It is shown that applying this method significantly improves bit error rate (BER) performance of digital FM using discriminator detection. Theoretical BER evaluation proves the superiority of this method, and establishes the optimum values for fundamental transmitter parameters. Experimental results are provided to support the superiority of this method.
TL;DR: A unified method for approximating and bounding the average bit error probability for spread-spectrum multiple-access communication systems is presented and it is shown that the same approach can be exploited for evaluating two classes of upper and lower bounds on the bit error rate.
Abstract: A unified method for approximating and bounding the average bit error probability for spread-spectrum multiple-access communication systems is presented. Various forms of direct-sequence spreadspectrum modulation are considered including binary phase-shift keying, quadriphase-shift keying, and minimum-shift keying. The analysis of the multiple-access interference makes use of a number of moments sufficent to evaluate the error probability with a high degree of accuracy. A computationally efficient algorithm for computing the moments is also given. The subsequent transformation from the moments to the average bit error probability is carried out by means of Gauss-type numerical integration formulas. It is shown that the same approach can be exploited for evaluating two classes of upper and lower bounds on the bit error rate. Finally, some results and comparisons are reported.
TL;DR: This paper provides performance analyses of a broad spectrum of error-correcting codes in an antijam communication system under worst-case partial-band noise jamming conditions and demonstrates the coding advantages available for systems operating with and without frequency diversity.
Abstract: This paper provides performance analyses of a broad spectrum of error-correcting codes in an antijam communication system under worst-case partial-band noise jamming conditions. These analyses demonstrate the coding advantages available for systems operating with and without frequency diversity. Utilizing both the exact approach (where possible) and upper-bounding approaches (Chernoff and union bounds), the decoded bit error rates for typical error-correcting codes (binary and M -ary, block and convolutional) have been obtained, and these codes have been compared according to the E_{b}/N_{0} required to achieve a bit error rate of 10-5. The best performance is achieved with the use of M -ary signaling and optimum diversity with M -ary codes, such as Reed-Solomon block codes, dual- k convolutional codes, convolutional orthogonal codes, or concatenated codes.
Patent•
NEC1
TL;DR: In this paper, a bit error detection circuit for checking the quality of a transmission path by accurately predicting a true bit error rate (BER) despite changes in the operating point of a nonlinear element or fluctuations in the level of an input signal was proposed.
Abstract: A bit errror detection circuit for checking the quality of a transmission path by accurately predicting a true bit error rate (BER) despite changes in the operating point of a non-linear element or fluctuations in the level of an input signal. An inputted PSK-modulated carrier wave is separately phase demodulated by a recovered carrier wave and a phase modulated carrier wave. These two phase demodulated PSK-modulated carrier waves are inputted into separate discriminator circuits 412 and 413 having a common discrimination level where the difference between the outputs can be compared by the comparator circuit 409 to predict a true BER.
TL;DR: Objective and subjective performance results indicate that using the (7, 4) Hamming code to protect the most important 2D-DCT coefficients can substantially improve reconstructed image quality at a BER of 10-2.
Abstract: Theoretical and simulation results of using Hamming codes with the two-dimensional discrete cosine transform (2D-DCT) at a transmitted data rate of 1 bit/pixel over a binary symmetric channel (BSC) are presented. The design bit error rate (BER) of interest is 10-2. The (7, 4), (15, 11), and (31, 26) Hamming codes are used to protect the most important bits in each 16 by 16 transformed block, where the most important bits are determined by calculating the mean squared reconstruction error (MSE) contributed by a channel error in each individual bit. A theoretical expression is given which allows the number of protected bits to achieve minimum MSE for each code rate to be computed. By comparing these minima, the best code and bit allocation can be found. Objective and subjective performance results indicate that using the (7, 4) Hamming code to protect the most important 2D-DCT coefficients can substantially improve reconstructed image quality at a BER of 10-2. Furthermore, the allocation of 33 out of the 256 bits per block to channel coding does not noticeably degrade reconstructed image quality in the absence of channel errors.
TL;DR: The problem of designing an adaptive receiver with an M -bit memory for binary orthogonal signaling over a slowly fading Rayleigh channel is considered and the results indicate that decision-feedback should be employed in a manner dependent on the SNR.
Abstract: We consider the problem of designing an adaptive receiver with an M -bit memory for binary orthogonal signaling over a slowly fading Rayleigh channel. Both the cases of decision-feedback and no decision-feedback are considered. We present a problem formulation by defining the contents of the receiver's memory. The structure of the Bayes receiver that makes optimum use of the memory information is then established. The LRT that defines the receiver is obtained explicitly, and it dictates a detector-estimator receiver structure. The detector can be interpreted as being partially coherent, with coherence being achieved asymptotically in the limit of perfect estimation of the fading process. Simulation results are given to show the improved error rate performance of the adaptive receiver. Our results also indicate that decision-feedback should be employed in a manner dependent on the SNR.
Patent•
03 Apr 1984
TL;DR: In this article, an error correction packet (e.g., bit in error) is sent to the decoder to correct a single bit error occurring in a sequence of data bits.
Abstract: Apparatus to permit the correction of a single bit error occurring in a sequence of data packets (e.g. bytes) comprising data bits. An encoder produces an error correction packet (e.g. byte), the value of which is determined algebraically from the value of bits in the data sequence. All data packets and the error correction packet have a predetermined parity. A decoder receives the sequence of data packets and error correction packet. If a single bit error in the data bits has occurred during transmission, one data packet is identified as having in it the bit in error. Algebraically, the data bit in error is identified and corrected.
Patent•
03 Jan 1984
TL;DR: In this article, a picture data record/playback system is presented, where picture data and code data are recorded onto two fields of a record, which fields constitute a single picture in an optical disk unit.
Abstract: In a picture data record/playback system, picture data and code data is recorded onto two fields of a record, which fields constitute a single picture in an optical disk unit. When the picture data is subjected to a cyclic redundancy check and an error is detected, the first error correction, for which the bit error rate of error correction is not too high, is applied to the picture data. The code data is doubly recorded onto the optical disk unit. Both items of recorded data are compared to each other. When such items are not coincident with each other, the CRC check is applied to both items of data which are doubly recorded. The valid code data is then selected. Further, when an error is detected, a CPU executes a second error correction, under program control, of which the bit error rate for error correction is not too low.
TL;DR: Digitized voice quality in a digital channel incorporating a 16 kbit/s ADM CODEC and GMSK coherent detection was compared with voice quality of a conventional analog FM channel and digital voice quality is inferior to that of analog voice.
Abstract: In this paper 16 kbit/s digital voice transmission with conventional channel spacing of 25 kHz, employing a 16 kbit/s adaptive delta modulation (ADM) coder-decoder (CODEC) is evaluated. The main characteristics of narrow-band digital FM modulation schemes, such as tamed FM, Gaussian filtered minimum shift keying (GMSK), four-level FM and phase locked loop-quaternary phase shift keying (PLL-QPSK), are compared by laboratory tests. Digitized voice quality in a digital channel incorporating a 16 kbit/s ADM CODEC and GMSK coherent detection was compared with voice quality of a conventional analog FM channel. Bit error ratio (BER) performance is shown to depend primarily on demodulation schemes. Digital voice quality is inferior to that of analog voice with an opinion score difference of about 0.5 in fading environments. This kind of digital voice transmission will be applicable for those systems that require high security at an expense of speech quality.
Patent•
05 Sep 1984
TL;DR: In this paper, the authors present a decoding apparatus for reading the digital data and producing an analog signal corresponding to the n data bits and the clock information bit, and circuitry for reconstructing the data in response to the analog signal.
Abstract: Digital data formatted on a data storage medium, in which the medium has a plurality of bit cells and the data format is such that groups of n data bits of an N-bit data word are stored over n consecutive bit cells, respectively, and a clock information bit is stored between the groups at every n+1 bit cell. A decoding apparatus includes circuitry for reading the digital data and producing an analog signal corresponding to the n data bits and the clock information bit, circuitry for reconstructing the digital data in response to the analog signal, and circuitry for producing data-ready pulses at a time corresponding to the bit cells storing the n data bits and for inhibiting the data-ready pulses at a time corresponding to the bit cell storing the clock information bit.
TL;DR: In this article, a transmission experiment was performed to study the high-speed potential of a long-distance gigabit lightwave system employing a single-frequency 1.5 μm laser and a new long wavelength III-V avalanche photodetector.
Abstract: A transmission experiment was performed to study the high-speed potential of a long-distance gigabit lightwave system employing a single-frequency 1.5 μm laser and a new long wavelength III–V avalanche photodetector. A 120 km length of standard production single mode fibre was used in the test, in which a bit error rate of 2×10−10 was achieved at 1 Gbit/s. This distance is the longest reported to date for rates higher than 500 Mbit/s, and the product of bit rate and distance (120 km Gbit/s) is the highest value achieved for any bit rate. The distance was limited by the 32.3 dB loss of the transmission path together with a total of 5.6 dB in power penalties associated with chirp broadening of the laser line.
TL;DR: Three different and compatible techniques are presented to improve the quality of the intermediate approximations of progressive transmission: use of smoother interpolation schemes in its generation, a nonuniform decomposition procedure to favor the early refinement of relevant areas of the image, and an extension of the transmission hierarchy to pixel quantization producing successive refinement of the grey level resolution of the approximation.
Abstract: Progressive transmission of images has proved to be an efficient way of reaching effective bit rate reductions in highly interactive contexts such as telebrowsing systems, or low bandwidth communication channels. However, the lack of quality of the intermediate approximations has so far limited the obtained effective compression to a small factor. Three different and compatible techniques are presented to improve this quality: use of smoother interpolation schemes in its generation, a nonuniform decomposition procedure to favor the early refinement of relevant areas of the image, and an extension of the transmission hierarchy to pixel quantization producing successive refinement of the grey level resolution of the approximations. Combined use of these approaches yields effective bit rate reductions of up to 12.5:1, considerably extending the range and power of progressive transmission methods.
Patent•
27 Jun 1984
TL;DR: In this article, a protection system of the type wherein a transmitter repeats identical information for plural times and by inverting polarity is proposed. But this scheme is not suitable for the case where the receiver evaluates the receiving condition and receives selectively the identical information which has been repeatedly transmitted.
Abstract: Fast and deep fading tends to occur in the communication between a fixed base station and a mobile station which is carried on an automobile travelling in an urban area. When connection control signals or other digital code pattern need to be transmitted between the mobile station and the fixed station, it is necessary to provide a protection system against fading. This invention relates to a protection system of the type wherein a transmitter repeats identical information for plural times and by inverting polarity. The bit error rate against fading will be thus improved and moreover, even if there is a deviation in the pattern arrangement of codes, the DC component unbalance may be avoided. The receiver evaluates the receiving condition and receives selectively the identical information which has been repeatedly transmitted. The invention provides plural circuit systems which are effective for evaluation and selection.
TL;DR: The approach used in simulating communications channels on the computer is described and examples are given that apply to the communications satellite channel; however, the techniques described are applicable to general channel configurations.
Abstract: Computer modeling of satellite communications channels is a valuable adjunct to analytical modeling and hardware simulation for predicting and verifying communications link performance. In the computer simulation approach, sampled signals are created in the computer and operated on by algorithms that simulate the effects of filtering, channel nonlinearities, interference, and noise. After passage through the simulated channel, the distorted signals are demodulated to determine the performance degradation introduced by the channel. This paper describes the approach used in simulating communications channels on the computer. Examples are given that apply to the communications satellite channel; however, the techniques described are applicable to general channel configurations.
TL;DR: The error rate performance of M -ary DPSK systems is investigated in the presence of phase change offset, noise correlation, and power imbalance, and it is found that the M-ary case is less sensitive to imbalance than is the binary case, and the satellite link performance depends strongly upon the quality of the uplink.
Abstract: The error rate performance of M -ary DPSK systems is investigated in the presence of phase change offset, noise correlation, and power imbalance. Both the terrestrial channel and the hard-limiting satellite repeater channel are considered. In the satellite repeater case, the noise correlations and power imbalances are assumed to be present on both the up- and downlinks. The emphasis is on exact results, or asymptotic approximations obtained therefrom, as opposed to error rate bounds. Most of the results are given in terms of integrals readily evaluated by quadrature. Performance curves showing the effects of the various impairments are presented. Some specific conclusions which follow from the results are that 1) the phase change offset is relatively unimportant for M \geq 4 , 2) the M -ary case is less sensitive to imbalance than is the binary case, and 3) the satellite link performance depends strongly upon the quality of the uplink.
TL;DR: It is shown that high transmission efficiency can be obtained in comparison with the other frequency-offset transmitter diversity, and the diversity effect on the bit error rate (BER) performance is equivalent to that of postdetection equal gain combining diversity.
Abstract: Transmitter diversity is a technique that is effective for mitigating signal transmission degradation caused by multipath fading which is one of the most serious problems in land mobile radio. A frequency-offset transmitter diversity is proposed for a land mobile radio system that employs minimum-shift keying (MSK) and two-bit differential detection. It is shown that high transmission efficiency can be obtained in comparison with the other frequency-offset transmitter diversity. In addition, the diversity effect on the bit error rate (BER) performance is equivalent to that of postdetection equal gain combining diversity. The BER performance improvement was confirmed by the experimental test results.