Combined frequency and differential phase shift keying withnon-coherent detection in a satellite mobile channel

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 power and bandwidth efficient when compared with other systems with constant envelope (or nearly constant envelope) and noncoherent detection like L-ary DPSK (LDPSK), Gaussian minimum shift keying (GMSK) and MSK     

Error probability of digital modulation in satellite mobile, landmobile, and Gaussian channels with narrow-band receiver filter

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 formulas are available for the Gaussian channel. The modification of the formulas involves only a redefinition of the noise power and autocorrelation function. Since the SMC contains as special cases the land mobile (Rayleigh) channel and the Gaussian channel, the derived formulas are valid for these channels as well. In fact the formula for the land mobile channel is in many cases reduced to a closed form, which does not contain an integral. The author computes the error probability for the four systems, and compares their performance assuming a third-order butterworth filter and M=2,4,8 symbols     

GMSK with frequency-selective Rayleigh fading and cochannelinterference

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 rejects a specified amount of adjacent channel interference. A formula for the error floor is also presented. Numerical results are presented for Gaussian minimum shift keying with a premodulation normalized filter bandwidth of 0.25. Under mild channel conditions and low energy-to-noise ratios, the best detector is an optimized two-bit differential detection; otherwise the best detector is the limiter discriminator detector     

Baseband pulse shaping to improve M-ary FSK in satellitemobile systems

Baseband pulse shaping is proposed to improve the performance of M-ary FSK with limiter discriminator integrator detection in a satellite mobile channel. Numerical results obtained for binary, quaternary, and octonary signaling with a Gaussian and a third-order Butterworth IF filter indicate that pulse shaped signals perform significantly better than frequency shift keying (FSK) signals. The error rate floor in the presence of a Doppler shift is also analyzed. Numerical results indicate that the error rate floor of pulse-shaped signals is significantly lower than that of FSK signals     

Error rate performance of noncoherent detection of duobinary coded MSK and TFM in mobile radio communication systems

Two continuous phase constant envelope modulation schemes are considered for use in digital mobile radio communication systems. These two schemes, duobinary coded minimum shift keying (MSK) and tamed frequency modulation (TFM), use partial response signaling to achieve efficient power spectrum. Therefore, they are suitable candidates for the application of digital data transmission via mobile radio where spectrum efficiency is an important consideration. The mobile communication channel is characterized by fast Rayleigh fading and cochannel interference resulting from the reuse of the channels. The error rate performance of duobinary coded MSK and TFM has been studied under these environments with noncoherent detection. A closed form expression for the probability of error of duobinary coded MSK with discriminator detection has been derived and evaluated for different cases of fast and slow fading and cochannel interference. The probability of error of duobinary coded MSK and TFM with differential detection has been calculated by numerical integrations for different cases of slow and fast fading and cochannel interference.     

Probability of error analysis of digital partial responsecontinuous phase modulation with noncoherent detection in mobile radiochannels

An analysis is presented of noncoherent detection of constant-envelope digital partial-response continuous-phase modulation (PRCPM) in fast Rayleigh fading that characterizes land mobile radio channels. Closed-form expressions for the probability of error are derived for limiter discriminator detection, and both 1- and 2-bit differential detection. Numerical results are presented for cases of practical interest to researchers and designers of land mobile radio systems. The expressions derived for the probability of error are general and can be used for all PRCPM schemes     

GMSK with differential phase detection in the satellite mobilechannel

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 channel, the input signal is the sum of a direct component, a diffuse component, and white Gaussian noise. The receiver is either with or without decision feedback, and the decision region is optimized for 2-b DPD to minimize the error probability. The error probability for GMSK is computed as a function of signal-to-noise ratio and other system or channel parameters (Doppler frequency, Gaussian filter bandwidth, ratio of powers in the direct and diffuse signal components, etc.). It is shown that decision feedback is more effective for GMSK with narrow bandwidth. The 2-b DPD is superior to the 1-b DPD for low Doppler frequencies and signal-to-noise ratios. For practical vehicle velocities and bit rates, a 2-b DPD with decision feedback outperforms all other analyzed schemes when the signal-to-noise ratio is low     

Relation between bit and symbol error probabilities for frequencyshift keying with limiter-discriminator detection

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 may be questionable. The authors compute the exact values of bit error probability as a function of energy-to-noise-ratio per bit for Gaussian, Rayleigh and Rician channels. They also compute the relative error involved in this approximation     

Digital transmission through a land mobile satellite channel

An analytical derivation of the probability of bit error noncoherent frequency-shift keying (FSK) and coherent phase-shift keying (PSK) signals transmitted through a land-mobile satellite channel is described. The channel characteristics used in the analysis are based on a recently developed model which includes the combined effects of fading and shadowing. Analytical expressions for the probability of bit error of FSK and coherent phase-shift keying (CPSK) signals are obtained. The results show that large amounts of signal-to-noise ratio (SNR) are required to compensate for the combined effect of fading and shadowing. An analytical expression for the irreducible probability of bit error of a CPSK signal due to phase variations caused by fading and shadowing is derived. The results described should be useful in the design of land mobile satellite communication systems     

M-ary FSK with limiter discriminator integrator detection and DPSK with differential phase detection in a Rician Fading channel

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.     

GMSK with limiter discriminator detection in satellite mobilechannel

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 error probability is computed as a function of energy-to-noise ratio, Gaussian filter bandwidth, Doppler frequency, maximum Doppler frequency, the ratio of powers in the specular and diffuse signal components, and the time delay between specular diffuse components     

Error probability in Nakagami-Rice channel

The error probability for differential phase shift keying (DPSK) and noncoherent frequency shift keying (FSK) signals transmitted through a severe fading channel termed as Nakagami-Rice channel is derived and is compared with the error probability for the well-known Rayleigh channel.     

阴影移动卫星信道中采用DPD和MRC的PRCPM的检测性能

本文给出了阴影移动卫星信道中采用差分相位检测(DPD)和最大比组合(MRC)的部分响应连续相位调制(PRCPM)信号的检测性能,并给出了实际阴影移动卫星信道中该方案的检测性能数值计算结果.     

Probability of error and outage in a Rice-lognormal channel forterrestrial and satellite personal communications

This letter addresses performance evaluation in a nonselective fading channel modeled by a combination of Rice and lognormal (RLN) statistics. The RLN model is valid under widely different environmental conditions, both for terrestrial cellular and for satellite personal communication systems. The letter provides semianalytical expressions for the average error probability in the RLN channel for coherent M-ary phase shift keying (PSK) and noncoherent M-ary orthogonal transmissions, then it highlights the relationship between outage probability and cell coverage for macro and microcellular systems, and finally it provides some error probability results for nongeostationary (non-GEO) satellite systems     

Soft-decision differential phase detection of turbo-coded M-ary CPFSK signals over Ricean channels

The performance of turbo codes is examined over the Ricean fading channel with soft-decision differential phase detection (DPD). M-ary continuous phase frequency-shift keying (CPFSK) signaling and puncturing of the coded sequence are considered to achieve bandwidth efficient communication. The effects of the number of phase decision regions, fading conditions, number of states of the constituent codes, and code rate are examined. A bit error rate upper bound is developed, which is useful at low values of bit error probability where computer simulations are lengthy. Significant gains using soft-decision DPD over hard-decision DPD and conventional noncoherent detection are reported.     

On the effect of cochannel interference on average error rates inNakagami-fading channels

The effect of cochannel interference on the performance of digital mobile radio systems in a Nakagami-fading channel is studied. Closed-form expressions are derived for the average probability of error of both coherent and noncoherent (differentially coherent) binary frequency shift keying and phase-shift keying schemes in an interference-limited system. The analysis assumes an arbitrary number of independent and identically distributed Nakagami interferers. The effect of maximal ratio combining diversity is also examined     

BER improvement of PRCPM in mobile radio channels withdiscriminator detection using decision feedback equalization

The authors investigate the bit error rate (BER) improvement of partial-response continuous-phase modulation (PRCPM) signals in mobile radio channels, when decision feedback equalization (DFE) to cancel the effect of intersymbol interference (ISI) of one adjacent bit is added to the limiter discriminator. A closed-form expression for the average probability of error as a function of the Doppler shift is derived for discriminator detection with decision feedback. Numerical results are presented to compare the BER performance of discriminator detection with and without feedback equalization     

M-ary frequency shift keying withlimiter-discriminator-integrator detector in satellite mobile channelwith narrowband receiver filter

An expression is derived for the error probability of M-ary frequency shift keying with a limiter-discriminator-integrator detector and a narrowband receiver filter in the satellite mobile channel. This channel contains, as special cases, the Gaussian and Rayleigh (land mobile) channels. The error probability is computed as a function of various system parameters for M=2, 4, 8 symbols and a third-order Butterworth receiver filter     

Performance evaluation of differential and discriminator detection of continuous phase modulation

Recently, bandwidth efficient constant-amplitude digital modulation schemes have also been shown to be power efficient when coherent detection is used. Partial-response continuous phase modulation (CPM) schemes are within this class. In some applications noncoherent detection is preferred. The performance of CPM systems is analyzed for differential and discriminator detection. An additive white Gaussian channel is assumed. The detectors make symbol-by-symbol decisions. The considered schemes are M-ary with an arbitrary modulation index and pulse shaping over several symbol intervals. The performance is analyzed by means of error probability expressions. The IF filter for the detectors is optimized within a special class of filters to give good performance. The differential detector is also analyzed on a Rayleigh fading channel. The fading is assumed to be slow. The IF filter is also optimized on this channel. Simulated error probabilities for discriminator detection with a Viterbi detector are also presented both for the Gaussian and the Rayleigh fading channel. The discriminator detector making symbol-by-symbol decisions is simulated on the Rayleigh fading channel. It is shown that partial-response CPM schemes with good performance can also be obtained with noncoherent detectors.     

The effect of pulse shaping and transmitter filter on theperformance of FSK-DPD and CPM-DPD in satellite mobile channel

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_T=4 and N_R=3, respectively, and the frequency shaping pulse is rectangular or raised cosine. It is shown that in all cases of practical interest, continuous phase modulation (with raised cosine pulse shaping) gives a lower bit-error probability and requires less bandwidth than frequency-shift keying (with rectangular pulse shaping) when all other parameters (number of symbols, Rician factor of the channel, order of filters, etc.) are the same