Ultra wide-band (UWB) communication holds great potential for a significantly improved data rate in future wireless systems. Accurate channel estimation and synchronization are critical for successful operation of a U...
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Ultra wide-band (UWB) communication holds great potential for a significantly improved data rate in future wireless systems. Accurate channel estimation and synchronization are critical for successful operation of a UWB system. We propose in this letter a completely blind channel estimation algorithm for UWB systems that employ pulse-positionmodulation, assuming perfect synchronization at the receiver. The algorithm exploits the first-order cyclostationarity in the received signal and performs certain circular deconvolution. The complexity is extremely low: Only some "overlap-add" operations and fast Fourier transform operations are needed. The algorithm is capable of simultaneously estimating multiple (say, more than 60) channel taps, and there is no ambiguity in either the amplitude or the phase of the estimated channel. It is shown that using estimated channel from 500 information symbols, the performance can approach that with a known channel within 3 dB in signal-to-noise ratio for a bit error rate of 0.001.
In this letter, a new nanocommunication modulation scheme termed multi-level pulse position modulation (ML-PPM) is proposed. The ML-PPM approach will boost the link capacity of a nanocommunication system while achievi...
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In this letter, a new nanocommunication modulation scheme termed multi-level pulse position modulation (ML-PPM) is proposed. The ML-PPM approach will boost the link capacity of a nanocommunication system while achieving a processing gain in reception. The bit error rate and link capacity of the scheme are evaluated using a non-coherent energy detection nanoreceiver. Simulation results show that the proposed scheme has a substantially greater link capacity than the existing schemes including time-spread on-off keying (TS-OOK) and M-ary pulse position modulation (PPM). (C) 2022 The Author(s). Published by Elsevier B.V. on behalf of The Korean Institute of Communications and Information Sciences.
pulse waveforms for 60 GHz impulse radio (IR) communication systems are investigated. The power spectral densities of the pulses are examined for compliance with Federal Communications Commission (FCC) spectral regula...
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pulse waveforms for 60 GHz impulse radio (IR) communication systems are investigated. The power spectral densities of the pulses are examined for compliance with Federal Communications Commission (FCC) spectral regulations. The error probability and capacity of M-ary pulse position modulation (PPM) 60 GHz IR systems with a correlation receiver using different pulse waveforms are analysed. Both orthogonal and non-orthogonal PPM is considered with additive white Gaussian noise and IEEE 802.15.3c channel models. Analytical and simulation results are presented, which show that an autocorrelation function that decays quickly provides a lower probability of error and better capacity. Among the pulse waveforms examined in this study, the truncated sinc pulse is the best in terms of compliance with FCC regulations and the PPM error probability and capacity.
An original analysis is presented for n(k)-ppM in which the information is conveyed by the position of k pulses, each within their own frame of n slots, giving n(k) PPM symbols. Comparisons are made with multiple PPM ...
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An original analysis is presented for n(k)-ppM in which the information is conveyed by the position of k pulses, each within their own frame of n slots, giving n(k) PPM symbols. Comparisons are made with multiple PPM (MPPM) and it is demonstrated that n(k)-PPM offers improved orthogonality, a simplified circuit implementation and comparable receiver sensitivity.
The effect is examined of multipath dispersion on the information and cut-off rates of multiple-pulse position modulation. Over multipath channels, intersymbol interference (TSI) can reduce the information rate signif...
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The effect is examined of multipath dispersion on the information and cut-off rates of multiple-pulse position modulation. Over multipath channels, intersymbol interference (TSI) can reduce the information rate significantly. When the input codewords are independent and identically distributed with a uniform distribution, lower and upper bounds are presented for the information rate on a moderate ISI channel in terms of the average mutual information of a memoryless Gaussian vector channel with scaled input codewords. The cut-off rate of each modulation scheme is also examined in the presence of ISI, and the power required to achieve the cut-off rate is calculated for various bit rates over the channel 3 dB bandwidth.
pulsepositionmodulation (PPM) has been used in the radio-frequency (RF) domain to achieve both low-dissipation requirements and provide precision ranging. In ultrawideband (UWB) architectures, it underpins an asynchr...
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pulsepositionmodulation (PPM) has been used in the radio-frequency (RF) domain to achieve both low-dissipation requirements and provide precision ranging. In ultrawideband (UWB) architectures, it underpins an asynchronous receiver, multiple access environments, and interference-resistant transmission. When combined with frequency hopping (FH), it allows for an additional level of immunity to jamming and low probability of intercept. Realization of a FH-PPM transceiver poses a practical challenge, particularly in the UWB RF range. With UWB pulses reaching the multi-gigahertz range, FH adds to the effective bandwidth at which the receiver must be operated, exceeding the performance of a modern quantizer and digital demodulation backplane. This study describes a new photonics-assisted FH-PPM receiver architecture that rests on mutually coherent frequency combs. The performance of the new receiver was characterized by receiving and decoding an 80-Mb/s rate FH-PPM UWB signal.
The use of pulse-coded signals over each colour component on a colour shift keying (CSK) modulation is explored. This codification improves the time-synchronisation recovery capability on the IEEE 802.15.7 PHY III sta...
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The use of pulse-coded signals over each colour component on a colour shift keying (CSK) modulation is explored. This codification improves the time-synchronisation recovery capability on the IEEE 802.15.7 PHY III standard and reduces the overall system complexity. Different symbol codification rates are studied so as to improve the symbol error rate while minimising the effect over the throughput of the whole system.
In this work, we study the performance analysis of underwater optical wireless communication (UOWC) transmission link by incorporating optical code division multiple access (OCDMA) using pulse position modulation (PPM...
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An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgme...
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An optical space time pulse position modulation(OSTPPM) scheme is proposed to satisfy the communication requirement of high transmission rate and better reliability. For the OSTPPM scheme, an improved threshold judgment-based orthogonal matching pursuit(IT-OMP) algorithm with low-complexity and near optimal performance is proposed. The average bit error rate of OSTPPM-IT-OMP scheme is investigated over the exponential Weibull channel, and its analytical expression is verified via Monte Carlo simulation. With the same simulation parameters, the signal to noise ratio of(4,4,2)-OSTPPM-IT-OMP is respectively 3.75 d B and 8.5 d B better than that of spatial pulse position modulation(SPPM) scheme and generalized spatial pulse position modulation(GSPPM)scheme at a bit error rate of 1 × 10-3. With the same transmission bits per symbol, the computational complexity of(3,4,2)-OSTPPM-IT-OMP scheme is reduced by 90.47% and 75.4% compared with(16,4,2)-SPPM and(5,4,2)-GSPPM schemes, respectively.
The laser beam propagating in the ground-to-satellite laser communication system is affected by intensity scintillation due to atmospheric turbulence and pointing errors due to beam wander. These effects would greatly...
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