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1.
The performance of constant envelope digital partial response continuous phase modulation (PRCPM) with two-bit differential detection and offset receiver diversity is theoretically analyzed in fast Rayleigh fading channels. A simple closed-form expression for the probability of error is derived and evaluated for cases of practical interest to researchers and designers of land mobile radio systems. It is shown that the dynamic bit error rate (BER) performance is considerably improved using the offset diversity scheme. Thus, many PRCPM signals having a compact power spectrum can be used in future digital mobile radio systems  相似文献   

2.
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  相似文献   

3.
Discriminator detection of Gaussian minimum shift keying in a land mobile radio environment is analyzed. Simple closed-form expressions for the average probability of error are presented and evaluated for cases of practical interest.  相似文献   

4.
The effect of intersymbol interference (ISI) of Gaussian filtered minimum shift keying (GMSK) on the probability of error of twobit differential detection is analyzed theoretically in fast Rayleigh fading characterizing land mobile radio channels. A closed form expression is derived for the probability of error. Numerical results are presented for cases of practical interest to researchers and designers of cellular land mobile radio systems.  相似文献   

5.
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.  相似文献   

6.
The effect of intersymbol interference (ISI) of Gaussian filtered minimum shift keying (GMSK) on the probability of error of one bit differential detection is analyzed theoretically in fast Rayleigh fading characterizing land mobile radio channels. A closed-form expression is derived for the probability of error as a function of the fading rate, IF filter bandwidth, signal-to-noise ratio (SNR) and ISI. Numerical results are presented for cases of practical interest to researchers and designers of cellular land mobile radio systems.  相似文献   

7.
Adachi  F. 《Electronics letters》1992,28(7):623-625
The intersymbol interference (ISI) produced by multipath channel delay spread can be approximated as Gaussian noise. The equivalent average signal-to-noise power ratio (SNR) is defined. Very simple expressions for average bit error rate (BER) due to delay spread are derived for linear quaternary DPSK (QDPSK) transmission with differential detection over mobile radio Rayleigh fading channels.<>  相似文献   

8.
9.
The error probability results shown by I. Korn (see ibid., vol.38, no.11, p.1980-6, 1990) indicate that the error floor is higher for systems with decision feedback (DF). It was concluded that DF gives a lower error probability only for smaller values of the normalized bandwidth BtT of the premodulation Gaussian filter, higher values of the ratio of powers in the direct and diffuse signal components K, and a lower range of signal-to-noise ratio. It is shown that this conclusion is not correct by theoretically analyzing the case of the land mobile channel where K=0 (or -∞ dB) and deriving a simple closed-form expression for the error probability for 1 bit differential detection with DF. It is shown that DF reduces the error probability for all values of BtT and signal-to-noise ratios. The formula derived can be easily evaluated not only for Gaussian minimum shift keying (GMSK) but for all partial-response continuous-phase-modulation (PRCPM) signals  相似文献   

10.
A series of error sequence measurements in a typical mobile radio channel has been conducted to study the time distribution of transmission errors. E.N. Gilbert's (1960) and B.D. Fritchman's (1967) digital communication channel models are shown to describe adequately the observed error bursts occurring in the mobile radio channel. An estimation method based on the gradient algorithm is proposed for computing the parameters values of both models from the experimentally derived error distributions. A digital mobile radio channel simulator based on Gilbert's and Fritchman's models with the parameter values as estimated using the gradient technique is presented  相似文献   

11.
The capture phenomenon and its consequences in nonbitsynchronous mobile packet radio networks for binary phase-shift-keying (BPSK) and differential phase-shift-keying modulation are investigated. Exact values of the bit error probability for given signal-to-noise ratios of colliding BPSK signals are derived. Packet error rates, which are needed for analysis of slotted random multiple access methods, are obtained by simulation. Two kinds of mobile radio channels are considered: the Rayleigh fading channel and the land mobile satellite channel. In the latter, because of shadowing, the probability that one of several colliding data packets is correctly received can be on the same order as the probability that a single packet that is not experiencing a collision is correctly received. The influence of Reed-Solomon codes on packet error probabilities is also studied. A slotted ALOHA system using the land mobile satellite channel is analyzed. It is found that with significant shadowing, the overall system throughput may reach the point-to-point throughput. Also, the code rate cannot be optimized in a straightforward manner by assuming one single transmission at a time  相似文献   

12.
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.  相似文献   

13.
Random FM noise using two-branch selection combining with correlated Rayleigh fading signals is analyzed for land mobile radio systems. General expressions are derived for the cumulative distribution function and mean square value of the random FM noise; they can be applied to any type of diversity such as space, polarization, etc. Calculated results show that, if two horizontally spaced antennas parallel with the direction of vehicle motion are used at a mobile station, random FM noise can be significantly reduced for small antenna spacings  相似文献   

14.
This letter presents an analysis of the error probability for noncoherent orthogonal multiple frequency-shift keying (MFSK) signals with postdetection square-law combining (SLC) when the signals transmitted over additive white Gaussian noise (AWGN) and slow frequency-nonselective arbitrarily correlated Nakagami-m fading channels. New exact expressions in a onefold integral for the probability of error of MFSK signals with postdetection square-law diversity combining operating in AWGN channel as well as in arbitrarily correlated Nakagami-m fading channels are derived. The effects of arbitrarily values of fading severity parameter m and the arbitrarily correlation between the L diversity channels are considered. The derived expressions can be easily computed, and hence, can be usefully exploited in the performance evaluation of digital mobile radio systems.  相似文献   

15.
The effect of cochannel interference on the performance of digital mobile radio systems in a Rayleigh fading environment is studied. The average bit error rate (BER) of an antenna array system with an optimum combining scheme that maximizes the output signal-to interference-plus-noise ratio is analyzed. BER expressions which are easy to evaluate numerically are derived for coherent binary phase-shift keying schemes in an environment with cochannel interference and noise  相似文献   

16.
Error-rate performance of a digital FM with differential detection in the presence of both thermal Gaussian noise and cochannel interference is theoretically analyzed in the fast Rayleigh fading environment encountered in the typical UHF or microwave land mobile radio channels. The temporal correlation of the fades is included in the performance analysis. The error probability is presented by a simple closed form for the important situations where both effects of Gaussian noise and cochannel interference predominate in causing errors. Finally, a comparison with the other detection schemes, e.g., discriminator and coherent detections, is given.  相似文献   

17.
Turbo-codes which are applicable to speech transmission in digital mobile radio systems are treated. Three turbo-codes of different complexity are presented. The proposed turbo-codes are suitable for the application to speech transmission in the joint detection code-division multiple access (JD-CDMA) mobile radio system with coherent receiver antenna diversity (CRAD) which are described concisely. The performance of the designed turbo-codes in terms of bit and frame error rates are shown in the case of additive white Gaussian noise (AWGN) channels, flat Rayleigh fading channels, and in the uplink of the aforementioned JD-CDMA mobile radio system  相似文献   

18.
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.  相似文献   

19.
The error rate performance of a binary differentially encoded phase-shift keying (DPSK) system in the presence of both thermal noise and multiple co-channel interferers is theoretically analyzed in the fast Rayleigh fading environment encountered in the typical UHF or microwave land mobile radio channels. The main objective is to show the additional degradation of an error rate of a binary DPSK system when undesired multiple co-channel M-ary DPSK interferers are virtually generated in a practical land mobile radio channel. The error probabilities are presented by a simple closed form as a function of noise correlation, interferer correlation, the number of interferers, M-ary modulating phase of interferer, Doppler frequency, carrier-to-noise (CNR) and carrier-to-interference (CIR) average power ratios.  相似文献   

20.
Trellis-coded continuous phase modulation (TC-CPM) schemes are attractive for bandwidth and power limited communication systems such as mobile satellite communications and land mobile radio communications. A coherent receiver for interleaved partial response TC-CPM is derived. A true upper bound on the bit error probability for flat fading channels is derived by showing that TC-CPM is equivalent to a trellis-coded modulation scheme. The upper bound is evaluated by defining an error-state diagram along with a set of characteristic distances and then applying transfer function bounding techniques. Comparison with simulation results shows the upper bound tight to within 1.5-2 dB  相似文献   

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