A capacity-achieving scheme based on polar codes is proposed for reliable communication over multi-channels which can be directly applied to bit-interleaved coded modulation schemes. We start by reviewing the ground-b...
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ISBN:
(纸本)9781467346481
A capacity-achieving scheme based on polar codes is proposed for reliable communication over multi-channels which can be directly applied to bit-interleaved coded modulation schemes. We start by reviewing the ground-breaking work of polar codes and then discuss our proposed scheme. Instead of encoding separately across the individual underlying channels, which requires multiple encoders and decoders, we take advantage of the recursive structure of polar codes to construct a unified scheme with a single encoder and decoder that can be used over the multi-channels. We prove that the scheme achieves the capacity over this multi-channel. Numerical analysis and simulation results for BICM channels at finite block lengths shows a considerable improvement in the probability of error comparing to a conventional separated scheme.
Digital network coding improves the throughput of the two-way relay channel by allowing multiple sources to transmit simultaneously to the relay. This work considers the development of a relay receiver applying a spec...
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ISBN:
(纸本)9781467331227
Digital network coding improves the throughput of the two-way relay channel by allowing multiple sources to transmit simultaneously to the relay. This work considers the development of a relay receiver applying a specific modulation and channel coding technique - turbo-coded noncoherent orthogonal FSK in the two-way relay channel operated with digital network coding. The relay receiver supports any modulation order which is a power of two, and iterative channel decoding with information feedback from decoder to demodulator, using bit interleaved coded modulation with iterative decoding (BICM-ID). The performance of the receiver is investigated in fading channels through error-rate simulations and capacity analysis, and results show an energy efficiency improvement of 0.5-0.9 dB over similar systems which do not utilize BICM-ID.
We conduct the first experimental study of the performance of link quality-based routing metrics in an 802.11n wireless mesh network (WMN). Link quality-based metrics have been shown to significantly outperform the tr...
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ISBN:
(纸本)9781467359467
We conduct the first experimental study of the performance of link quality-based routing metrics in an 802.11n wireless mesh network (WMN). Link quality-based metrics have been shown to significantly outperform the traditional hopcount metric but they have only been evaluated over legacy 802.11a/b/g radios. The new 802.11n standard introduces a number of enhancements at the MAC and PHY layers (MIMO technology, channel bonding, frame aggregation, short guard interval, and more aggressive modulation and coding schemes) marking the beginning of a new generation of 802.11 radios. Our study in a 21-node indoor 802.11n WMN testbed reveals that the gains of link quality-based metrics over the hopcount metric in legacy 802.11 WMNs do not carry over in 802.11n MIMO WMNs. We analyze the causes of this behavior and make recommendations for the design of new routing metrics in 802.11n WMNs.
The traditional cross-layer model for video streaming can achieve significant improvement to the end-to-end video quality. However, the video quality measurement in terms of sum of squared error (SSE) in the model doe...
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ISBN:
(纸本)9781467331333;9781467347358
The traditional cross-layer model for video streaming can achieve significant improvement to the end-to-end video quality. However, the video quality measurement in terms of sum of squared error (SSE) in the model does not always correlate well with the perception of the human visual system. In this paper, we propose a perceptual quality driven cross-layer optimization scheme based on the structural similarity (SSIM) index for wireless video streaming. The H. 264/AVC encoding parameters on the application layer and the modulation and channel coding modes on the physical layer are mainly considered to optimize the end-to-end perceptual video quality. In order to decrease the computation complexity, a low complexity optimization algorithm based on the rate-quantization (R-Q) model is proposed to reduce the range of the candidate optimization parameters. Experimental results show that the proposed SSIM-based cross-layer optimization scheme achieves better perceptual quality than the SSE-based cross-layer optimization scheme, and the proposed low complexity optimization algorithm can achieve about 62% computation decrease compared to the conventional exhaustive searching algorithm with little loss in perceptual quality.
A framework is proposed that allows for a joint description and optimization of both binary polar coding and the multilevel coding (MLC) approach for 2(m)- ary digital pulse-amplitude modulation (PAM). The conceptual ...
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ISBN:
(纸本)9781479904464
A framework is proposed that allows for a joint description and optimization of both binary polar coding and the multilevel coding (MLC) approach for 2(m)- ary digital pulse-amplitude modulation (PAM). The conceptual equivalence of polar coding and multilevel coding is pointed out in detail. Based on a novel characterization of the channel polarization phenomenon, rules for the optimal choice of the bit labeling in this coded modulation scheme employing polar codes are developed. Simulation results for the AWGN channel are included.
Bit interleaved coded modulation with four dimensional mapping using single parity check coding is discussed for high spectral efficiency transoceanic transmission systems.
ISBN:
(纸本)9781457715075
Bit interleaved coded modulation with four dimensional mapping using single parity check coding is discussed for high spectral efficiency transoceanic transmission systems.
Efficient exploitation of the wide bandwidth available in the EHF (extremely high frequency) domain will be a main pillar for the development of future-generation terabit satellite networks. State-of-the-art systems u...
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ISBN:
(纸本)9781467318112
Efficient exploitation of the wide bandwidth available in the EHF (extremely high frequency) domain will be a main pillar for the development of future-generation terabit satellite networks. State-of-the-art systems use spectrally-efficient coded modulations, which are based on coherent demodulation that requires the use of complex and expensive analog PLL circuitry, which are vulnerable to high Doppler shifts and phase noise, the latter, being a significant impairment in the W-band. The latest trends in digital communications are to use fully digital receivers. Therefore, we consider a novel modulation method based on differential turbo-coded modulation and A-Posteriori-Probability (APP) channel estimation for application in multi-gigabit W-band satellite links. The proposed scheme utilizes the combination of an outer 2/3 binary parity channel code and differential 8-PSK modulation, similar to a binary repeat-accumulate serial turbo coding. The turbo-demodulator uses a double-spread interleaver and Log-MAP decoding performed on the 8-PSK trellis. Counteracting channel impairments and frequency drifts is primarily accomplished by APP channel estimation which is integrated into the differential demodulator, and consists of a simple smoothing filter. Preliminary results have shown a robust behavior of the system, achieving high link availability.
Widespread use of wireless LAN (WLAN) may soon cause an over-crowding problem in use of the ISM spectrum. One way in which this manifests itself is the low Received Signal Strength Indication (RSSI) at the WLAN statio...
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ISBN:
(纸本)9781467300094;9781467352871
Widespread use of wireless LAN (WLAN) may soon cause an over-crowding problem in use of the ISM spectrum. One way in which this manifests itself is the low Received Signal Strength Indication (RSSI) at the WLAN stations, impacting performance. Meanwhile, the IEEE 802.11 standard is being evolved and extended, for example with new coding schemes and the 802.11n standard, which makes use of 5GHz and 2.4GHz. An application's performance requirements may dictate the choice of technology determined by RSSI levels. We report on measurements of the upper and lower bounds of performance with good and poor RSSI in 802.11g and 802.11n. We find that in operation under poor (low) RSSI, performance is indeed impacted. In some cases the impact is such that there may be little benefit in using the newer 802.11n over 802.11g.
In 2002, Federal Communications Commission (FCC) was the first in defining regulations for ultra wideband (UWB) communications followed by Europe and Japan some years later. Focusing on impulse radio (IR) UWB, in 2007...
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ISBN:
(纸本)9781457702167
In 2002, Federal Communications Commission (FCC) was the first in defining regulations for ultra wideband (UWB) communications followed by Europe and Japan some years later. Focusing on impulse radio (IR) UWB, in 2007 was the time for the first published standard targeting in personal area networks, released by the IEEE. The second IEEE released standard including UWB definitions is targeted for wireless body area networks (WBAN) and was published in 2012. As the wireless communications has been and will be passing through almost any levels in society, the natural step with WBAN is using it in different medical, healthcare and wellbeing applications. The arguments for these are related to the modern lifestyle, in which people have increasingly more free time and are more interested in taking care of their health and wellbeing. Another challenge is the population composition, i.e., aging in developed countries which call for new solutions and procedures, particularly from cost wise. In this paper, we are evaluating UWB receivers based on the IEEE 802.15.6 physical layer definitions and capable of detecting differentially encoded modulation. The evaluation is performed using two different WBAN channel models.
Non-binary symbol transmission such as Ternary Phase Shift Keying (TPSK) and Hexagonal Quadrature Amplitude modulation (HQAM) can achieve the superior performance to the PSK or square QAM in the band-limited and peak-...
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ISBN:
(纸本)9781467361873
Non-binary symbol transmission such as Ternary Phase Shift Keying (TPSK) and Hexagonal Quadrature Amplitude modulation (HQAM) can achieve the superior performance to the PSK or square QAM in the band-limited and peak-to-average power ratio (PAPR) limited channel due to its excellent natures of PAPR, spurious characteristic, and minimum Euclidean distance. However, these non-binary symbol transmissions are not suitable for the transmission of binary information, because there is mapping loss in the bit-to-symbol mapping due to non-power-of-two number of constellation points. The aim of this work is to alleviate its loss by using spatial modulation and then improve the bit-error performance. Spatial modulation has been proposed as a spatial domain modulation, which can efficiently work only in the case of power-of-two number of antennas. By jointly desingning spatial modulation and non-binary amplitude-phase modulation, the system can be more flexibly designed and then achieve better performance. Furthermore, we study the coding scheme for this non-binary symbol transmission in the PAPR limited channel. Computer simulations confirm that the proposed system with non-binary turbo code can significantly improve BER performance.
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