Shannon Channel Capacity Research Articles

Evaluating the level of inteference in UMTS/LTE heterogeneous network system

<p>The study evaluated interference in a dense heterogeneous network using third-generation universal mobile telecommunication systems (UMTS) and fourth-generation long term evolution (LTE) networks LTE. The UMTs/LTE heterogeneous network determines the level of interference when the two communication systems coexist and how to improve the network by migrating from UMTs to LTE, which has a faster download speed and larger capacity. Techno lite 8 on third generation (3G) and Infinix Pro 6 on fourth generation (4G) were used to measure network the received signal strength (RSS) during site investigation. UE interference was detected and traced using a spectrum analyzer. UMTS and LTE path loss exponents are 2.6 and 3.2. Shannon's capacity theorem calculated LTE and UMTS capacity. When signal to interference and noise ratio (SINR) was used as a quality of service (QoS) indicator, MATLAB channel capacity plots did not match Shannon's due to neighboring interference. UMTS had an R2 of 0.54 and LTE 0.57 for the Shannon channel capacity equation. Adjacent channel interference (ACI) user devices reduce network capacity, lowering QoS for other customers.</p>

On Optimal Channel Capacity Theorems via Verma Information Measure with Two-sided Input in Noisy State

The capacity for which the value or is its lower bound is referred to as the optimal channel capacity. Through this communication, we attempt to study the additive Gaussian interference that arises from the Gaussian channel's two-sided state information, which is non-causally known at both the transmitter and receiver and reliant on the channel's noise and input . Verma entropy maximized using normal distribution is noted by the author. He contrasts Verma's channel capacity with Shannon's channel capacity during this investigation, which has implications for communication technology.

Millimeter-Waves to Terahertz SISO and MIMO Continuous Variable Quantum Key Distribution

With the exponentially increased demands for large bandwidth, it is important to think about the best network platform as well as the security and privacy of the information in communication networks. Millimetre (mm)-waves and terahertz (THz) with high carrier frequency are proposed as the enabling technologies to overcome Shannon's channel capacity limit of existing communication systems by providing ultrawide bandwidth signals. Mm-waves and THz are also able to build wireless links compatible with optical communication systems. However, most solid-state components that can operate reasonably efficiently at these frequency ranges (100GHz-10THz), especially sources and detectors, require cryogenic cooling, as is a requirement for most quantum systems. Here, we show that secure mm-waves and THz QKD can be achieved when the sources and detectors operate at cryogenic temperatures down to <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</i> = 4K. We compare single-input single-output (SISO) and multiple-input multiple-output (MIMO) Continuous Variable THz Quantum Key Distribution (CVQKD) schemes and find the positive secret key rate in the frequency ranges between <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> =100 GHz and 1 THz. Moreover, we find that the maximum transmission distance could be extended, the secret key rate could be improved in lower temperatures, and achieve a maximum secrete communication distance of more than 5km at <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> =100GHz and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</i> =4K by using 1024×1024 antennas. Our results for the first time show the possibility of mm-waves and THz MIMO CVQKD with the system operating at temperatures below <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</i> = 50K, which may contribute to the efforts to develop next-generation secure wireless communication systems and quantum internet for applications from inter-satellite and deep space to indoor and short-distance communications.

Mutual Information and Multi-Agent Systems.

We consider the use of Shannon information theory, and its various entropic terms to aid in reaching optimal decisions that should be made in a multi-agent/Team scenario. The methods that we use are to model how various agents interact, including power allocation. Our metric for agents passing information are classical Shannon channel capacity. Our results are the mathematical theorems showing how combining agents influences the channel capacity.

METHODS AND TOOLS FOR ASSESSING THE LEVEL OF NOISE IMMUNITY OF WIRELESS COMMUNICATION CHANNELS

The subject of this article is the process of increasing the noise immunityof wireless channels in the construction or operation of modern digital communication systems (DCS), when the transmission of digital information significantly complicates the presence of interference and distortion in the communication channel. The aim is analysis and development of methods for ensuring stable and reliable operation of ultra-wideband wireless communication system in the conditions of interference and distortion of information in wireless communication channels. The task is creation and implementation of practical recommendations for improving the level of secrecy and quality of information circulating in the communication channel; development of criteria for quality, information efficiency and noise immunityof DCS wireless communication channels in the conditions of interference of natural and artificial origin. The methods used: methods of analytical modeling and the theory of potential noise immunity. The following results were obtained. The feasibility of assessing the DCS efficiency by two indicators - energy and frequency efficiency, which are the components that make up the overall integral indicator of informational efficiency was shown. It was proposed to evaluate the DCS efficiency by comparing the indicators of informational efficiency of the inverse and reference systems, using the Shannon limit as an ideal ratio of energy and frequency efficiency. On the basis of the theory of potential noise immunity it was shown that it is possible to operate wireless communication channels in conditions when the level of information signal and noise have the same value. Conclusions. It is shown that the use of the technology of supersmooth signals allows to carry out wireless redundant transmission of information with low impromptu capacity. Moreover, the efficiency of digital communication systems significantly increases due to the creation of an ensemble of complex signals through one-time encoding and modulation, which expands its information base, ensuring coverage and energy efficiency in a double symmetric channel. This enables the fullest possible utilization of the channel's Shannon capacity with high integrity of information transfer without a significant increase in the signal-to-noise ratio at the receiver's input. An integral indicator of informational efficiency of the wireless DCS communication channel is provided. It enables real-time integral assessment of link quality and optimal routing in a mobile peer-to-peer network – MANET.

Performance analysis of short-packet communications with incremental relaying

In the fifth generation (5G) cellular system, short-packet communication is a key enabler to support critical applications, i.e., ultra-reliable low-latency communications (URLLCs), where finite block-length codewords are adopted. However, the short-packet communication suffers from a higher decoding error rate and has a lower transmission rate than the Shannon channel capacity. To improve both the reception reliability and the transmission efficiency, the incremental relaying (IR) is considered to improve the performance of the short-packet communication. Especially, we investigate an IR scheme for short-packet communications to reduce the transmission delay. To evaluate the system performance, closed-form expressions for the decoding error probability, the throughput and the delay are derived by considering the feedback overhead of IR. Finally, we provide simulation results to verify the accuracy of the theoretical analysis, and also compare the proposed IR scheme with the direct transmission (DT) and conventional relaying transmission (RT) schemes. Simulation results verify the effectiveness of the proposed IR scheme for the short-packet communication.

Investigating Suitable Multiple Access Techniques for Harbor Wireless Communication Systems

The multiple access communications for harbor environment are suffering from both low quality transmission due many metallic obstacles and overloaded networks due to the huge number of users/devices of logistic monitoring. This paper proposes a coded random access (CRA) scheme with a degree distribution suitable for harbor environment to serve many devices and provide communications with high reliability. The degree distribution is optimized using extrinsic information transfer (EXIT) charts by keeping that two EXIT curves do not intersect at low mutual information points. Since we are working on the network level, of which the benefit of broadband communications is kept for the fairness with the narrowband transmission, we convert the gain of broadband transmissions into an equivalent gain to the narrowband transmissions based on the Shannon channel capacity and coding theory. We then compare CRA to carrier sense multiple access with collision avoidance (CSMA/CA), because CSMA/CA has better performance compared to other techniques, such as ALOHA and Slotted ALOHA. We evaluate the performance of the proposed CRA and CSMA/CA using a series of computer simulation in additive white Gaussian noise (AWGN) and multipath Rayleigh fading channels in terms of throughput and packet-loss rate (PLR). The results confirmed that CRA with the proposed degree distribution is more suitable than CSMA/CA as a multiple access technique for harbor wireless communications, indicated that the proposed CRA has higher throughput and lower PLR. The results of this study are expected to contribute to the development of future harbor communication systems.

Propagation of rays in 2D and 3D waveguides: A stability analysis with Lyapunov and reversibility fast indicators.

Propagation of rays in 2D and 3D corrugated waveguides is performed in the general framework of stability indicators. The analysis of stability is based on the Lyapunov and reversibility error. It is found that the error growth follows a power law for regular orbits and an exponential law for chaotic orbits. A relation with the Shannon channel capacity is devised and an approximate scaling law found for the capacity increase with the corrugation depth.

Adaptive Resource Optimization For Cognitive Radio Networks

In cognitive radio network, the spectrum sensing finds either the channel is occupied or idle, the problem is assigning the unused channels of the primary user (PU) to the secondary users in an efficient manner is most challenging issue. In this work, we investigates the above issue and proposed an adaptive resource allocation to the secondary users in terms of channel allocation and power allocation. The proposed work intelligently handles both frequency and space efficiently without affecting the quality of service (QoS) of the primary user. We considered both underlay and overlay spectrum access, based on that resource allocation is carried out in an efficient manner. The maximum transmitted data rate of the secondary user (SU) obtained is 225Kbps determined by using Shannon channel capacity theorem. The proposed work also shows the effectiveness of the simulation in terms of energy efficiency up to 8.25 x 105 bits/Joule.

On the Achievable Rate Under Finite Codelength for RIS-Aided Systems

The ideal Shannon channel capacity can only be achieved by infinite codelength, so it is not accurate for practical finite codelength. The codelength of channel coding schemes heavily affects the performance of communication systems, but it cannot be too long to ensure affordable decoding complexity and latency. Unfortunately, existing performance analysis for systems aided by reconfigurable intelligent surface (RIS) only focus on the ideal channel capacity and neglect the achievable rate loss caused by finite codelength. To fill in this gap, this paper analyzes the achievable rate under finite codelength in a time-coherent RIS-aided systems, and gives an approximate analytic solution based on Taylor expansion and multi-dimensional central limit theorem. To be more specific, the closed form approximated achievable rate is given based on Taylor expansion, and it is shown that the required codelength decreases superlinearly with the increase of the number of RIS elements. Simulation results verify the analysis, and demonstrate the advantage of RIS-aided systems over the traditional large antenna array schemes.

Towards a Unified Theory of Learning and Information.

In this paper, we introduce the notion of “learning capacity” for algorithms that learn from data, which is analogous to the Shannon channel capacity for communication systems. We show how “learning capacity” bridges the gap between statistical learning theory and information theory, and we will use it to derive generalization bounds for finite hypothesis spaces, differential privacy, and countable domains, among others. Moreover, we prove that under the Axiom of Choice, the existence of an empirical risk minimization (ERM) rule that has a vanishing learning capacity is equivalent to the assertion that the hypothesis space has a finite Vapnik–Chervonenkis (VC) dimension, thus establishing an equivalence relation between two of the most fundamental concepts in statistical learning theory and information theory. In addition, we show how the learning capacity of an algorithm provides important qualitative results, such as on the relation between generalization and algorithmic stability, information leakage, and data processing. Finally, we conclude by listing some open problems and suggesting future directions of research.

HUMIDITY EFFECT TO 5G PERFORMANCES UNDER PALEMBANG CHANNEL MODEL AT 28 GHZ

The telecommunication has a tremendous improvement in terms of data rates and bandwidth requiring sufficient frequency allocation and wideband spectrum availability. The millimeter-wave frequency band is one of the solution to these requirements, however communications in this band is facing new challenges on the climate effect to the channel propagation In this paper, we propose a 5G channel model considering the effect of humidity based on the characteristic of the natural environment of Palembang city. The channel model is represented by power levels and delay called a Power Delay Profile (PDP and is derived based on a series of computer simulations using parameters of nature in Palembang. The 5G channel model is important to further derive the outage performance to be used as the theoretical performance of 5G in Palembang since the the Shannon Channel Capacity Theorem is involved in the derivation. We conduct a series of computer simulations to evaluate the validity of the proposed channel model and its characteristics. We found that humidity affect to the performances, where high humidity makes the performances of outage and BER slightly worse, although the effect may be ignored for some applications. The results of this paper are expected to be the references for the development and implementation of 5G Networks especially at the mm-Wave band in Palembang.

Stabilization of Nonlinear Dynamic Systems Over Limited Capacity Communication Channels

This article addresses the stabilization of noiseless nonlinear dynamic systems over limited capacity communication channels. It is shown that the stability of nonlinear dynamic systems over memory-less communication channels implies an inequality condition between the Shannon channel capacity and the summation of the positive equilibrium Lyapunov exponents of the dynamic system or, equivalently, the logarithms of the magnitude of the unstable eigenvalues of system Jacobian. Furthermore, we propose an encoder, decoder, and a controller to prove that scalar nonlinear dynamic systems are stabilizable under the aforementioned inequality condition over the digital noiseless and the packet erasure channels, respectively, in sure and almost sure senses. The performance of the proposed coding scheme is illustrated by computer simulations.

Variable-Length Coding With Shared Incremental Redundancy: Design Methods and Examples

Variable-length (VL) coding with feedback is a commonly used technique that can approach point-to-point Shannon channel capacity with a significantly shorter average codeword length than fixed-length coding without feedback. This paper uses the inter-frame coding of Zeineddine and Mansour, originally introduced to address varying channel-state conditions in broadcast wireless communication, to approach capacity on point-to-point channels using VL codes without feedback. The per-symbol complexity is comparable to decoding the VL code with feedback (plus the additional complexity of a small peeling decoder amortized over many VL codes) and presents the opportunity for encoders and decoders that utilize massive parallel processing, where each VL decoder can process simultaneously. This paper provides an analytical framework and a design process for the degree distribution of the inter-frame code that allows the feedback-free system to achieve 96% or more of the throughput of the original VL code with feedback. As examples of VL codes, we consider non-binary (NB) low-density parity-check (LDPC), binary LDPC, and convolutional VL codes. The NB-LDPC VL code with an 8-bit CRC and an average codeword length of 336 bits achieves 85% of capacity with four rounds of ACK/NACK feedback. The proposed scheme using shared incremental redundancy without feedback achieves 97% of that performance or 83% of the channel capacity.

Spatial information theory of sensor array and its application in performance evaluation

The direction of arrival (DOA) and amplitude-phase (AP) of source signal can be estimated through array signal processing, while the process of information acquisition has not been described by information theory yet. In this study, the authors propose a novel spatial information theory framework to describe the DOA and AP estimation process. Firstly, they give a sensor array system model, where the spatial information is defined mathematically. Furthermore, in a single source scenario, the derivations of theoretical expression and an asymptotic upper bound for DOA information are presented. It also proves that the AP information accords with Shannon channel capacity when the source follows complex-Gaussian distribution. In addition, when in an uncorrelated multi-sources scenario, the AP information is the sum of that of each source for Gaussian distributed sources. Finally, they propose a definition of entropy error to evaluate the information acquisition capability of a sensor array. Numerical results verify that the entropy error is consistent with mean square error and approaches Cramer–Rao bound in high signal-to-noise ratio. It also verifies the correctness of theoretical derivation and shows that the spatial information can be employed as an evaluation index to quantitatively analyse the system performance which has significant guidance.

Design and Optimization for Distributed Compress-and-Forward System based on Multi-Relay Network

A novel distributed compress-and-forward (CF) system based on multi-relay network is presented. In this system, as the direct link between the source and destination is invalid due to some reasons, such as the limited power, special working environment, or even economic factors, relays are employed to receive analog signals and carry on distributed compressed encoding. Subsequently, the digital signals are transmitted to the destination via wireless channel. Moreover, a theoretical analysis for the system is provided by utilizing the Chief Executive Officer (CEO) theory and Shannon channel capacity theory, and the rate-distortion function as well as the connection between the transmission rate and the channel capacity are constructed. In addition, an optimal signal-to-noise ratio (SNR) -based power allocation method is proposed to maximize the quantization SNR under the limited total power. Simulation result shows that the proposed CF system outperforms the amplify-and-forward (AF) system versus the SNR performance.

Multiplexing Zero-Error and Rare-Error Communications Over a Noisy Channel

Two independent data streams are to be transmitted over a noisy discrete memoryless channel with noiseless (ideal) feedback. Errors are tolerated only in the second stream, provided that they occur with vanishing probability. The rate of the error-free stream cannot, of course, exceed the channel's zero-error feedback capacity, and nor can the sum of the streams' rates exceed the channel's Shannon capacity. Using a suitable coding scheme, these necessary conditions are shown to characterize all the achievable rate pairs. Planning for the worst channel behavior-as is needed to achieve zero-error communication-and planning for the typical channel behavior-as is needed to communicate near the Shannon limit-are thus not incompatible. It is further shown that feedback may be beneficial for the multiplexing problem even on channels on which it does not increase the zero-error capacity.

Ratio List Decoding

We extend the notion of list decoding to ratio list decoding which involves a list decoder whose list size is specified as a function of the number of messages $M_{n}$ and the block length $n$ . We present the necessary and sufficient conditions on $M_{n}$ for the existence of code sequences which enable reliable list decoding with respect to the desired list size $L(M_{n},n)$ . It is shown that the ratio-capacity, defined as the supremum of achievable normalized logarithms of the ratio $r(M_{n},n)=M_{n}/L(M_{n},n)$ , is equal to the Shannon channel capacity $C$ , for both stochastic and deterministic encoding. Allowing for random list size, we are able to deduce some properties of identification codes, where the decoder’s output can be viewed as a list of messages corresponding to decision regions that include the channel output. We further address the regime of mismatched list decoding, in which the list constitutes of the codewords that accumulate the highest score values (jointly with the channel output) according to some given function. We study the case of deterministic encoding and mismatched ratio list decoding. We establish similar necessary and sufficient conditions for the existence of code sequences which enable reliable mismatched list decoding with respect to the desired list size $L(M_{n},n)$ , and we show that the ratio-capacity with mismatched decoding is equal to the mismatch capacity. Focusing on the case of an exponential list size $L_{n}=e^{n \Theta }$ , its comparison with ordinary mismatched decoding shows that the increase in capacity is by $\Theta $ bits per channel used for all channels and decoding metrics. Several properties of the average error probability in the setup of mismatched list decoding with deterministic list size are provided.

Analysis and Design of Broadband Simultaneous Wireless Information and Power Transfer (SWIPT) System Considering Rectifier Effect

The deployment of internet of things (IOT) devices in several applications is limited by their need of having batteries as a power source. This has led many researchers to make efforts on simultaneous wireless information and power transfer (SWIPT) systems design. Increasing the bandwidth provides higher capacity; however, due to the narrowband response of conventional power transfer subsystems, power delivery is decreased. In order to design an optimum wideband SWIPT system, first, a realistic model of the system, including antennas and rectifier, should be developed. Then, proper methods to increase the bandwidth of subsystems for optimum power delivery can be proposed. In this paper, a wideband SWIPT system (300 MHz bandwidth at the center frequency of 1.44 GHz) while considering realistic limitations of antennas and rectifiers is designed. To optimize the system performance, a novel power allocation method is proposed. Using this algorithm, Pareto fronts of Shannon channel capacity versus power delivery in three scenarios (broadband antennas without considering rectifier, broadband antennas with narrowband rectifier and broadband antennas with broadband rectifier) are compared. The results show that, without considering the realistic behaviour of the subsystems, the performance is largely overestimated. Furthermore, this model allows for designers to optimize each subsystem directly and assess its effect on the overall SWIPT system performance.

Relaying-Enabled Ultra-Reliable Low-Latency Communications in 5G

Supporting URLLC has become one of the major considerations in the design of 5G systems. In the literature, it has been shown that cooperative relaying is an efficient strategy to improve the reliability of transmissions, support higher rates, and lower latency. However, prior studies have demonstrated the performance advantages of relaying generally under the ideal assumption of communicating arbitrarily reliably at Shannon's channel capacity, which is not an accurate performance indicator for relaying in URLLC networks in which transmission is required to be completed within a strict time span and coding schemes with relatively short blocklengths need to be employed. In this article, we address the performance modeling and optimization of relaying-enabled URLLC networks. We first discuss the accurate performance modeling of relay-enabled 5G networks. In particular, we provide a comprehensive summary of the performance advantage of applying relaying in 5G URLLC transmissions in comparison to the case of direct transmission (without relaying). Both a noise-limited scenario and an interference- limited scenario are discussed. Then we present tools for performance optimization utilizing the knowledge of either perfect or average channel side information. Finally, we summarize the proposed optimization schemes and discuss potential future research directions.