I. Korn's research while affiliated with UNSW Sydney and other places

Publications (81)

Article
In this paper, an equation for the error probability of M-ary frequency shift keying with limiter-discriminator detection in Nakagami fading channels for arbitrary m is derived. The authors do the same for selection combining with L diversity channels for integer m and for switch and stay combining with two diversity channels for m=1 (Rayleigh fadi...
Article
Optimal signal energies are derived for optimal binary digital communication systems with arbitrary signal probabilities and correlation with both coherent and noncoherent detection. The resulting bit-error probability (BEP) is computed and compared with the BEP of the same systems with equal signal energies. One of the conclusions is that for the...
Article
The combined effect of imperfect magnitude and phase of fading estimates in maximal ratio combining (MRC) is analysed. Theoretical error rate bounds are derived under small estimate errors. These bounds are tested over Rayleigh and Nakagami-m fading channels with binary phase shift keying (BPSK) modulation, and verified using computer simulation. N...
Article
We derive an equation for the bit-error probability (BEP) of Gaussian minimum-shift keying with limiter discriminator detection in Nakagami-m fading channels including selection and switch-and-stay combining. We compute the BEP for various selections of system parameters.
Article
The effect of imperfect timing is analyzed in equal gain combining (EGC) and maximal ratio combining (MRC) techniques over Rayleigh and Nakagami-m fading channels with binary phase-shift keying modulation. In the case of EGC, the bit-error probability is derived, while in the case of MRC, error rate bounds are presented. Theoretical results are jus...
Chapter
In this paper, a method for optimizing the index map between the output indices of a wideband (7 kHz) CELP speech coder and the channel symbols for a power constrained channel and multilevel signaling is presented. The method is based on simulated annealing and makes use of dynamic scaling of a QAM signal constellation during the optimization proce...
Article
Soft-decision differential phase detection (SD-DPD) with Viterbi decoding is proposed for the detection of trellis-coded FSK signals over a fading channel. The soft detector detects the differential phase and chooses a subregion among a preselected set of subregions at the end of every interval. The effect of the number of subregions is studied. Th...
Article
An equation is derived for the bit error probability (BEP) of M-ary continuous phase modulation (CPM) with differential phase detection (DPD) and maximal ratio combining (MRC) in various fading channels. As an example, the BEP of Gaussian minimum shift keying with B <sub>g</sub>T=0.5 is computed. In the case of a Rician channel, the Doppler frequen...
Conference Paper
An un-phased equal gain combining (UEGC) technique, which simply adds signals from different diversity channels, is introduced and compared with maximum ratio combining (MRC) over a satellite mobile channel (SMC). It is demonstrated that the performance with UEGC can be calculated by analyzing an equivalent SMC without diversity. Numerical results...
Conference Paper
In this study, noncoherent sequence detection of trellis coded continuous phase frequency shift keying (CPFSK) signals is considered over Rician fading channels with maximum ratio combining (MRC) diversity. A soft decision differential phase detector (SD-DPD) that chooses a differential phase subregion among a preselected set of subregions at the e...
Article
We derive a formula for the bit-error probability (BEP) of binary partial-response continuous-phase modulation (PRCPM) with N-bit differential phase detection (DPD) in a Rician fading channel subject to L-branch maximum ratio combining (MRC) diversity. We compute the BEP for minimum-shift keying (MSK), Gaussian MSK (GMSK), and 2 RC (2-b-duration ra...
Article
The authors derive a formula for the bit-error probability (BEP) of a four-dimensional signal and coherent but simple detector in fading channels with Rician or Nakagami probability density function for the received signal envelope. They compute the BEP in both cases and show its dependence on the energy-to-noise ratio per bit, E/sub b//N/sub o/ an...
Article
The effect of bandlimiting filters in a receiver only and both transmitter and receiver on the bit error probability of a multidimensional digital communication system in a Gaussian channel is analysed. Numerical results are presented for fourth-order Butterworth filters in the receiver and either a third-order filter or no filter in the transmitte...
Article
In this paper the bit error probability (BEP) of narrowband M-ary differential phase shift keying with differential phase detection (MDPSK-DPD) and maximum ratio combining (MRC) in Rician fading channels is computed. Two systems shall be investigated. In the first system the transmitted pulse is a Nyquist pulse with bandwidth B = R(1 + β), where R...
Article
We analyze the performance of a multiamplitude and multidimensional digital communication system with a simple detector in the presence of additive white Gaussian noise (AWGN). We compute the power and spectral efficiency of this scheme and compare them with those of conventional schemes with three different pulses
Article
We derive a formula for the bit error probability (BEP) of M-ary continuous phase frequency shift keying with differential phase detection and maximum ratio combining diversity in Rician fast-fading channels. We assume that transmitter and receiver filters distort the signal and limit the noise. We compute the BEP as a function of energy-to-noise r...
Article
In this paper, we analyze the performance (power and bandwidth efficiency) of a scheme with multidimensional signals, and both optimal detector and nonoptimal but simple detector, and show that they are inferior to known schemes with narrowband Nyquist signals and optimal detectors
Conference Paper
We derive a formula for the bit error probability (BEP) of binary partial response continuous phase modulation (PRCPM) with differential phase detection (DPD) in a Rician fading channel subject to L-branch maximum ratio combining (MRC) diversity. We compute the BER for minimum shift keying (MSK), Gaussian minimum shift keying (GMSK) and 2RC (two bi...
Article
We study the effect of bandlimiting transmitter filter on the bit error probability (BEP) of M-ary Frequency Shift Keying and Differential Phase Shift Keying with Differential Phase Detector in Satellite Mobile Channel. Numerical results are presented in the case when the transmitter and receiver filters are Butterworth filters of order NT = 4 and...
Article
We analyze the performance of combined binary frequency and M-ary differential phase shift keying (2FSK/MDPSK) in the satellite mobile channel (SMC). We use two detectors in which the frequency symbol is detected by a limiter discriminator detector (LDD) and the phase symbol by a differential phase detector (DPD). It is shown that this system is po...
Article
The author computes the bit error probability of binary CPM with differential phase detection in a Rician fading channel using L-path maximum ratio combining diversity. The frequency pulses are rectangular, raised cosine and half sine of duration NT, N=1, 2, 3. The fading channel contains Doppler frequency shifts and time delays, hence it is both t...
Article
This paper investigates how a bandlimiting transmitter filter and the shape of the frequency pulse effect the bit-error probability of frequency shift keying with differential phase detection in satellite mobile channel. Numerical results are presented for the case when the transmitter and receiver filters are Butterworth filters of order N<sub>T</...
Article
The author comments on the paper by Korn (IEEE Trans. on Commun., vol.38, no.11, p.1980-6, 1990). It is pointed out that a statement in parentheses following equation (52) in the original paper should be removed. Some new conclusions are drawn to replace the earlier erroneous ones
Article
In M-ary, Gray coded DPSK, and FSK with differential phase detection the bit error probability is usually approximated by the symbol error probability divided by the number of bits in a symbol. This approximation is known to be excellent for PSK with large signal-to-noise ratios in a Gaussian channel. In other cases this approximation may be questi...
Article
In M-ary, Gray coded digital communication the bit error probability is usually approximated by the symbol error probability divided by the number of bits in a symbol. This approximation is known to be excellent for phase shift keying with coherent detection at high-signal-to-noise ratios and Gaussian channel. Here it is illustrated that this appro...
Article
In M-ary, Gray coded frequency shift keying with limiter discriminator detection the bit error probability is usually approximated by the symbol error probability divided by the number of bits in a symbol. This approximation is known to be excellent for phase shift keying with large energy-to-noise ratios and Gaussian channel. In other cases this m...
Article
The authors analyze the performance of quadrature-quadrature differential phase shift keying (Q<sup>2</sup>DPSK) in the satellite mobile channel. The expression for the bit error probability takes into account both intersymbol and cross-symbol interference (ISI and CSI). Numerical results are presented for three different pulse pairs. It is shown t...
Article
We study the effect of bandlimiting transmitter filter and frequency pulse shaping filter on the bit error probability of frequency shift keying with differential phase detection in satellite mobile channel. Numerical results are presented for the case when the transmitter and receiver filters are Butterworth filters of order NT=4 and NR=3 respecti...
Conference Paper
The authors analyse the performance of frequency/differential phase shift keying (2FSK/MDPSK) in the Satellite Mobile Channel (SMC) with a bandlimiting transmitter filter. They use two detectors in which the frequency symbol is detected by a limiter discriminator detector (LDD) and the phase symbol by a differential phase detector (DPD). The signal...
Conference Paper
The performance of quadrature-quadrature differential phase shift keying (Q<sup>2</sup>DPSK) in the satellite mobile channel is analyzed. The expression for the bit error probability takes into account both intersymbol and cross-symbol interference (ISI and CSI). Numerical results are presented for a sine, cosine pulse pair. It is shown that Q <sup...
Conference Paper
We analyse the performance of combined frequency and differential phase shift keying (2FSK/MDPSK) in the satellite mobile channel (SMC). We use two detectors in which the frequency symbol is detected by a limiter discriminator detector (LDD) and the phase symbol by a differential phase detector (DPD). The signal has a constant envelope. It is shown...
Conference Paper
In M -ary, Gray coded digital communication, the bit error probability is usually approximated by the symbol error probability divided by the number of bits in a symbol. This approximation is excellent for phase shift keying (PSK) with coherent detection at high-signal-to-noise ratios and Gaussian channel. The exact bit error probability for M -ary...
Article
The use of pulse shaping to combat the multipath propagation effect in Rician channels is proposed. Because of the time delay t<sub>d</sub> between the specular and diffuse signal components, pulse shaping can reduce their correlation. Analysis and numerical results are given.
Article
It is shown how to derive formulas for the error probability for M -ary differential phase shift keying with differential phase detection (DPD) and M -ary frequency shift keying with DPD, limiter-discriminator detection and limiter-discriminator-integrator detection in the satellite mobile channel (SMC) with narrowband receiver filter if such formu...
Article
The author derives a formula for error probability of partial-response continuous-phase modulation with differential phase detector and limiter discriminator detector in a multipath Rayleigh fading channel, taking into account frequency-selective fading, cochannel interference, Doppler frequency shift, and additive Gaussian noise while the receiver...
Conference Paper
A formula is derived for the error probability of partial response continuous phase modulation (CPM) with differential phase detection in a multipath Rayleigh fading channel taking into account frequency selective fading, co-channel interference, Doppler frequency shift and additive Gaussian noise while the receiver rejects a specified amount of ad...
Article
In a satellite mobile channel (SMC) and land mobile channel (LMC) because of fading and nonlinear power amplifiers, constant envelope modulation and noncoherent detection methods may outperform other schemes. It is shown how to compute the error floor for four noncoherent digital communication systems in satellite and land mobile channels. Differen...
Article
We derive formulae for the error probability of M-ary frequency shift keying with a limiter-discriminator detector in a satellite mobile channel, which includes as special cases the land mobile (Rayleigh) channel and the Gaussian channel. The received signal in this channel is composed of a specular signal, a diffuse signal and white Gaussian noise...
Article
A formula is derived for the error probability of M -ary differential phase-shift keying with differential phase detection in a two-path Rayleigh fading channel taking into account adjacent channel interference (ACI), cochannel interference (CCI), intersymbol interference (ISI), and Doppler frequency shift. Square-root Nyquist filters are used with...
Article
Formulas are derived to find the error probability of partial-response frequency-shift keying with limiter discriminator detection, with and without decision feedback, for a satellite-mobile channel. The special cases of a Gaussian channel and a land-mobile channel are discussed. The formulas are applied to Gaussian minimum shift keying, and the er...
Article
A formula is derived for the error probability of partial-response continuous-phase modulation (which contains Gaussian minimum shift keying (GMSK) as a special case) with N -b ( N =1, 2) differential phase detection (DPD) for the satellite mobile channel, which contains as special cases the Gaussian and Rayleigh channels. In the satellite mobile c...
Article
We derive an expression for the error probability of M-ary Frequency Shift Keying with Limiter Discriminator Detection (followed by a sample and hold filter) and narrowband receiver filter which is valid for the Gaussian channel, land mobile channel and satellite mobile channel. We compute the error probability as a function of energy-to-noise rati...
Article
A class of digital phase-modulated signals called DCPM (digital complex phase-modulated) signals is introduced. In this class, the imaginary part of the phase is obtained from the real part by a linear time-invariant transformation. A method for computing the autocorrelation function (ACF) of DCPM is presented. It is shown that the ACF does not alw...
Article
We derive an expression for the error probability of M-ary differential phase shift keying with differential phase detection and of M-ary frequency shift keying with limiter discriminator integrator detection which is valid for Rician. Rayleigh and Gaussian channels.
Article
The authors derive an expression for the error probability of M-ary frequency shift keying with differential phase detector and narrowband receiver filter in the satellite mobile (Rician) channel which includes as special cases the Gaussian and land mobile (Rayleigh) channels. They compute the error probability as a function of various system param...
Article
An expression is derived for the error probability of M -ary offset differential phase-shift keying (DPSK) with the differential phase detector and narrowband receiver filter in the satellite mobile (Rician) channel, which includes as special cases the Gaussian and land mobile (Rayleigh) channels. The error probability is computed as a function of...
Article
A formula is derived for the error probability of M -ary phase-shift keying (PSK) in the satellite mobile channel when the signal is accompanied by a pilot tone which is used in the receiver for coherent detection of the signal. The author computes the error probability as a function of the signal-to-noise ratio, the ratio of powers in the specular...
Article
The author derives a formula for the error probability of partial response frequency shift keying with limiter discriminator integrator detector with and without decision feedback for the satellite mobile channel which contains as special cases the Gaussian channel and the land mobile channel. The author applies the formulae to Gaussian minimum shi...
Article
A study of error probability of binary suppressed sideband (SSB) angle modulation in an additive white Gaussian noise channel with a phase detector receiver shows that SSB schemes can perform better than double sideband schemes at small system bandwidths.
Article
Formulas are derived for the error probability of M -ary frequency shift keying (FSK) with differential phase detection in a satellite mobile channel. The received signal in this channel is composed of a specular signal, a diffuse signal, and white Gaussian noise; hence, the composite signal is fading and has a Rician envelope. The error probabilit...
Article
The author computes the error probability for conventional and for symmetric differential phase shift keying (CDPSK and SDPSK) with differential detection in systems with binary, ternary and quaternary symbols, and with two kinds of filters. In the first system, the system response is a Butterworth filter with two, three and four poles, which cause...
Article
We show how to compute the error probability of frequency-shift keying with limiter-discriminator-integrator detection in the presence of narrowband filters in the transmitter and receiver when the symbols are pseudoternary, i.e. they are generated from binary symbols using duobinary, modified duobinary and dicode rules. We show numerical results a...
Article
In analysing an FSK system there is a need to compute the effect of narrowband filters on the modulated signal. In the letter we show how to do this directly and precisely for any piecewise-constant shaping function.
Article
Digital radio is affected by frequency-selective fading (FSF), which causes intersymbol interference (ISI), and by adjacent channel interference (ACI), which in its turn is also affected by the same FSF. Using a two-ray model for the FSF, the transfer function of the channel is H(f) = a[1 ¿ b exp ( ¿ j2¿¿(f ¿ f0))]. Outage in digital radio occ...
Article
We derive an equation for the error probability of M -ary frequency shift keying with a limiter-discriminator-integrator detector in the presence of narrow-band filters in the transmitter and receiver. We present numerical results for the case of quaternary symbols, wide-band transmitter filter, and Butterworth filter in the receiver with 2, 3, and...
Article
A very efficient technique for the computation of error probability in ASK systems with M = 2 m (m an integer) symbols or QASK systems with M2 symblos in the presence of intersymbols interference was presented by Jenq, Liu and Thomas, and this technique was extended by Jenq to coherent PSK (no phase jitter) with M = 2, 4 and 8 symbols. In the prese...
Article
In investigations of frequency shift keying (FSK) with a limiter-discriminator-integrator (LDI) detector it was assumed that the noise at two consecutive sampling points is uncorrelated. Here we study the effect of correlated noise on error probability. We show that the error probability is reduced when the correlation is positive and increased whe...
Article
Duplex transmission of digital signals on the single-pair subscriber line is possible if the signals in the two directions are sufficiently separated. An analogue adaptive hybrid is one method of signal separation. We discuss here the theory of analogue adaptive hybrids. We present a model for the system and the adaptive hybrid, and show the result...
Article
In the paper we study the effect of intersymbol, quadrature channel and adjacent channel interference (in addition to Gaussian noise) on the error probability of M-ary quadrature amplitude modulation (QAM) with M = 4, 16 symbols and phase shift keying (PSK) with M = 4, 8 and 16 symbols, which are special cases of quadrature amplitude shift keying (...
Article
In this paper we study the effect of intersymbol and quadrature channel interference on the average error probability of 16-ary offset quadrature amplitude modulation with rectangular or sinusoidal shaping functions. We present numerical results assuming that the transmitter and receiver filters are identical Butterworth filters of order N = 1,2,.....
Article
In this paper we present formulas for the computation of error probability in the presence of quadrature-channel or adjacentchannel interference in addition to intersymbol interference in a minimum shift keying system. The filters in the receiver and transmitter are arbitrary but with a finite number of poles. The effect of phase jitter in the main...
Article
The optimal receiver for a given transmitter and both the optimal receiver and transmitter are derived for a digital communication system in which the desired signal is of the partial-response type. The optimality criterion is the minimisation of the mean square error between the actual output and the desired output at the sampling time.
Article
In this paper, we derive a simple expression for the degradation in signal-to-noise ratio caused by intersymbol and adjacent channel interference in MSK systems for which the total response is nonnegative and the response is such that only two intersymbol and one adjacent channel terms are dominant. An MSK system with Gaussian filters in transmitte...
Article
Formulas are presented for the computation of error probability of OQPSK and MSK with narrow-band filters in transmitter and receiver and various detector filters (matched filter, sampling detector, rectangular filter and half-rectangular filter). Numerical results are computed for the case when the filters in transmitter and receiver are identical...
Article
A generalized minimum shift keying (GMSK) signal is defined, and its equivalence to a modified offset quadrature shift keying signal is shown. A simple formula for the spectrum of a GMSK signal is presented and the spectrum and out-of-band power are computed for two examples.
Article
The bandwidth in which 99 percent of the power is contained is presented for ASK, QASK, OQASK, PSK, FSK, and MSK. An example is given in which the bandwidth of FSK is one eighth the bandwidth of ASK and of the modulating signal. Error probability is presented for the various types of modulation with various detectors, detector filters and Butterwor...
Article
Minimum Shift Keying (MSK) is a method of modulation which can be viewed as a special case of Frequency Shift Keying or a special form of Offset Quadrature Phase Shift Keying; therefore, it can be detected either by a discriminator or with a pair of matched filters. In the latter case, the system is optimal, provided there are no bandlimiting filte...
Article
Formulas for probability of error (P e ) and probability of erasure (P o ) for a binary communication system with partial response signals (duobinary, dicode, modified duobinary) and either decision feedback or precoding are presented.The input data are binary,but the output data are ternary where the third symbol represents erasure.The system with...
Article
The effect of adjacent channel interference on the probability of error in a binary bandpass communication system with an integrating and dumping detector is investigated. Narrowband filters are assumed in the receiver of the main signal and transmitters of both main and interfering signals. Plots of the probability of error as a function of signal...

Citations

... QAM transmits the information data by modulating the amplitudes of two carrier waves, using straight amplitude modulation • Less sensitive, hence performs significantly with an increase in the mobile users [3] • Conserved the bandwidth efficiency [3] • High spectrum sensing resolution [3] • for the analog signal and Amplitude Shift Keying (ASK) for the digital signal. QAM requires linear amplifiers and coherent detection [59]. QAM has a moderate energy efficiency, excellent bandwidth, and complexity on the receiver side because it needs to track the frequency, phase, and amplitude of the carrier and also track the sampling time and symbol rate [59]. ...
... A new closed-form cumulative distribution function (CDF) of the differential phase is also derived. This CDF is different from those derived by Mason [B] and Korn [9], in that it includes the effects of IS1 and noise correlation; further, it does not contain a singular point in the entire range of the phase variable. Finally, we apply our CDF formula to compute the BER of 7r/4-as well as conventional DQPSK and compare their performance for various values of Doppler frequency shift and IF filter bandwidth. ...
... In order to demodulate the SSC separately a narrowband receiver filter is needed. In [3] it was shown that a third order butterworth filter is either optimal or close to optimal for the reception of FSK signals in the AWGN channel. The presence of other OFDM subcarriers brings additional noise into the filter bandwidth. ...
... Henceforth, M-ary FCMA is simulated assuming Rayleigh and Rician fading channels, to match the forgoing services. Rician fading suits satellite mobile channel whereas Rayleigh fading suits land mobile channel [5]. The restriction of the applications in satellite communications depends mainly on the socalled Rice factor. ...
... x 15 x 16 code. Another scheme, Frequency/Differential Phase Shift Keying (2FSK/MDPSK) [24], has two independent differential MPSK subsets created using binary FSK. ...
... They can also be used to implement highquality-factor frequency-selective filters and to realize biquadratic filters to synthesize quadrature and multiphase oscillators [2]–[4]. In addition, allpass filters are key components in the realization of time delays that find applications in differential modulation [5], transmit-reference systems [6], beamforming [7]–[9], and impulse radio ultra-wideband wireless receivers for synchronizing the received RF signal with the locally generated pulse signal [10], to name a few examples. Allpass filters have also been finding applications in circuits that conventionally relied on digital delay stages. ...
... MDPSK/DPD has been widely applied in mobile communications [6]- [8], because of its simplicity and robustness to the fading. There has been much effort on determining the error performance of MDPSK/DPD over fading channels [51]- [60]. The work of Korn [54]- [58] is particularly significant. ...
... Also, since we are interested in environments where a coherent phase reference is not available and because the complexity of coherent receivers [4], [5], [9] is quite large for the small modulation indices that we must use to attain the desired spectral efficiencies, noncoherent reception using the soft-decision differential phase detector (SDDPD) [15] is considered. The SDDPD was shown to outperform some popular differential detectors such as the limiter discriminator integrator [16] and the differential phase detector [17] in [18]. Different from [15] and [18], where the SDDPD with Viterbi decoding gives hard estimates of the modulated symbols, we develop a soft-out, SDDPD (SO-SDDPD) that generates bit-wise log-likelihood ratios (LLRs) for the modulated symbols. ...
... A basic work on analyzing and comparing performance of various digital modulation schemes in the presence of ACI can be found in [7]. Later, [8]- [10] addressed ACI analysis for offset phase-shift keying, differential phase-shift keying, and minimum shift keying, respectively. Reference [11] investigated the performance of a neuralnetwork-based receiver in the presence of ACI. ...
... This approach is then used to find out the degradation due to adjacent channel interference in M-PSK systems and M-QAM systems, which form the basis of EDGE technology. Earlier work has been done to find out the error rate caused due to adjacent channel interference for MSK systems [3], QPSK, 8-PSK, 16-QASK and QPR systems [4], but the equations derived for the above systems are not scalable when the order of modulation is of the order of 32 or more. Error probability equations for a multilevel continuous phase shift keyed systems in the presence of intersymbol, interchannel and co-channel interference are derived in [5], in which expressions for binary CPSK are derived whereas upper bound and lower bounds are presented for multilevel systems. ...