Maximum Transmission Rate Research Articles

The Asian Citrus Psyllid Host Murraya koenigii Is Immune to Citrus Huanglongbing Pathogen ‘Candidatus Liberibacter asiaticus’

The Asian citrus psyllid (ACP) Diaphorina citri, vector of 'Candidatus Liberibacter asiaticus' (CLas), the putative causal agent of citrus Huanglongbing (HLB), is controlled by application of insecticides, which, although effective, has resulted in serious biological imbalances. New management tools are needed, and the technique known as "trap crop" has been attracting attention. A potential plant for use as a trap crop in the management of the ACP is Murraya koenigii (curry leaf). However, for this plant to be used in the field, it needs to be attractive for the vector and must not harbor CLas. To verify the potential of curry leaf as trap crop for the management of HLB, we investigated the ability of D. citri to transmit CLas to M. koenigii, and to other test plants, including M. paniculata (orange jasmine) and cultivar Valencia sweet-orange seedlings. For the tests, the insects were reared on a symptomatic CLas-infected plant and allowed to feed on the three test plant species. The overall maximum transmission rate for the citrus seedlings was 83.3%, and for orange jasmine was 33.3%. Successful transmission of CLas by ACP to the curry-leaf seedlings was not observed, and it was treated as immune to CLas. Supported by the previous results that M. koenigii is attractive for ACP, these results indicate that curry leaf is an excellent candidate for use as a trap crop, to improve the management of the insect vector and consequently of HLB.

Youla Coding and Computation of Gaussian Feedback Capacity

In this paper, we propose an approach to numerically compute the feedback capacity of stationary finite dimensional Gaussian channels and construct (arbitrarily close to) capacity-achieving feedback codes. In particular, we first extend the interpretation of feedback communication over stationary finite dimensional Gaussian channels as feedback control systems by showing that, the problem of finding stabilizing feedback controllers with maximal reliable transmission rate over Youla parameters coincides with the problem of finding strictly causal filters to achieve feedback capacity derived in [2]. This extended interpretation provides an approach to construct deterministic feedback coding schemes with double exponential decaying error probability. We next propose asymptotic capacity-achieving upper bounds, which can be numerically evaluated by solving finite dimensional convex optimizations. From the filters that achieve the upper bounds, we apply the Youla-based interpretation to construct feasible filters, i.e., feedback codes, leading to a sequence of lower bounds. We prove the sequence of lower bounds is asymptotically capacity-achieving.

Rate-Maximized Scheduling in Adaptive OCDMA Systems Using Stochastic Optimization

In this letter, we use stochastic optimization to schedule data transmissions in an adaptive optical code division multiple-access (OCDMA) system to maximize transmission rate. We employ Lyapunov drift theory to formulate a general optimization problem for rate-maximized scheduling in which user codes are adaptively assigned such that time-averaged transmission rate is maximized and important system parameters such as stability and BER performance are maintained. Simulation results show that the overall transmission rate in a rate-maximized scheduled OCDMA system can be up to 3 (1.2) times better than the transmission rate in its counterpart OCDMA system with fixed code assignment scheme (with rate-efficient code allocation algorithm).

Optimized energy efficient route assigning method using related node discovery algorithm in MANET

Mobile nodes are normally dissimilar to each other in network, the path discovery process is perform to share data packets, but mobile nodes behavior and capacity is varied. Some nodes perform unpredictable packet sharing, therefore nodes energy level is different, so those nodes are shorten its communication from the source node to a destination node, the multipath routing also difficult to achieve a maximum packet transmission rate for the path node. It increases energy consumption and reduces network lifetime. So, proposed Optimized energy efficient route assigning (OEERA) method to provide better and more stable energy based routing path for similar node’s characteristics in a network environment. The related node discovery algorithm is planned in that network, this is applied to select the routing node for the particular path with similar or related nodes with its capacity, and characteristics. It is easy to offer predictable packet transmission in a specific path. This optimized energy efficient routing method is used to choose maximum steadiness node of path require to reduces energy consumption and improves network lifetime.

Influence mechanism of repetition frequency on pulse position modulation in deep space laser communication

Taking the deep space laser communication as the application background, based on multi-pulse position modulation and differential pulse position modulation, a new differential multi-pulse position modulation (DMPPM) mode is proposed. The DMPPM theory model is set up, and a comparative study and analysis of four modulation schemes of PPM, DPPM, MPPM and DMPPM has been developed. The simulation results show that the repetition rate of the pulse laser has a great influence on the four modulation modes. DMPPM has the characteristics of the smallest average symbol length, the largest average transmitting power, the maximum peak transmitting power, the maximum unit transmission rate, the smallest bandwidth demand and a higher transmission efficiency. The analysis shows that DMPPM is greatly influenced by the repetition frequency of the laser. It is very necessary to improve the repetition rate of the laser under the premise of ensuring the peak power of the pulse laser. DMPPM can become one of the excellent modulation schemes for deep space laser communication.

On Achievable Rates of AWGN Energy-Harvesting Channels With Block Energy Arrival and Non-Vanishing Error Probabilities

This paper investigates the achievable rates of an additive white Gaussian noise energy-harvesting (EH) channel with an infinite battery. The EH process is characterized by a sequence of blocks of harvested energy, which is known causally at the source. The harvested energy remains constant within a block while the harvested energy across different blocks is characterized by a sequence of independent and identically distributed random variables. The blocks have length $L$ , which can be interpreted as the coherence time of the energy-arrival process. If $L$ is a constant or grows sublinearly in the blocklength $n$ , we fully characterize the first-order term in the asymptotic expansion of the maximum transmission rate subject to a fixed tolerable error probability $\varepsilon $ . The first-order term is known as the $\varepsilon $ -capacity. In addition, we obtain lower and upper bounds on the second-order term in the asymptotic expansion, which reveal that the second order term is proportional to $-({L/{n}})^{1/2}$ for any $\varepsilon $ less than 1/2. The lower bound is obtained through analyzing the save-and-transmit strategy. If $L$ grows linearly in $n$ , we obtain lower and upper bounds on the $\varepsilon $ -capacity, which coincide whenever the cumulative distribution function of the EH random variable is continuous and strictly increasing. In order to achieve the lower bound, we have proposed a novel adaptive save-and-transmit strategy, which chooses different save-and-transmit codes across different blocks according to the energy variation across the blocks.

A method of determining maximum transmission rate in wireless sensor network

The lifetime of wireless sensor networks (WSNs) decreases with the increasing payload, such that extending the network lifetime has become a hot topic. This paper proposes a distance-based transmission rate sexlection algorithm, maximum emission rate (MER) determination, to select the pairwise maximum effective transmission rate in a given WSN environment. The proposed work is founded on two observations, one is the logarithmic relationship of internode communication distance to data transmission rate, the other is the linear relationship of receiving current to data transmission rate. The proposed work helps to reduce data transmission duration, and finally to increase the network lifetime. Simulation results show that the application of MER in existing network protocols extends 300% plus network lifetime while ensuring communication success rate.

Consistent Data Collection and Assortment in the Progression of Continuous Objects in IoT

In Internet of Things ( IoT )-based applications, one of the foremost application is the localization and detection of continuous objects, such as mud flow, forest fire, toxic gases, biochemical materials, and so forth. The localization and detection of continuous objects require massive communication which may cause congestion, exhaust extensive amount of energy, and cause severe packet loss. In this paper, we proposed consistent data collection and assortment in the progression of continuous objects in IoT ( CDCAPC) to tackle traffic congestion, continuous objects detection and throughput maximization problem, which employs the link capacity diversity, congested boundary node selection and node remaining power during the scheduling policy construction to reach maximum data transmission rate. The proposed algorithm is based on efficient utilization of network resources and variable data rates. The congestion is mitigated in hotspots by considering the differences of the link capacities in the sending process. The CDCAPC performance has been evaluated with promising results against equivalent scheme in term of data loss, high priority data packets delivery, end-to-end delay, hop-by-delay, and percentage of successfully received packets.

A method of determining maximum transmission rate in wireless sensor network

A method of determining maximum transmission rate in wireless sensor network

Overlapping Coalition Formation Game for Resource Allocation in Network Coding Aided D2D Communications

Due to spectrum sharing, device-to-device (D2D) communications underlaying cellular networks enhance system capacity significantly that benefits services of local area. On the other hand, network coding enables highly efficient cooperation, which increases the system capacity through code-and-forward mechanism. It is a challenging problem that how to allocate resource in the network coding aided cooperative D2D communications. In this paper, we first design a network coding aided cooperative diversity scheme for D2D communication, and derive the system transmission rate with the consideration of interference. Then, we formulate the problem of joint spectrum resource allocation and relay selection as an overlapping coalition formation game, where one relay is able to serve multiple coalitions to increase the system capacity. For each coalition, maximum bipartite graph matching model is established to select the optimal relay to achieve the maximum transmission rate. Finally, to solve the formulated game problem, we propose a distributed algorithm based on switch operations with low computation complexity. Extensive numerical results demonstrate that our solution increases the system transmission rate by about 30-40 percent without bringing extra computation complexity, compared with other state-of-the-art schemes.

Research and performance analysis on multi-point light-emitting diodes-array intra-vehicle visible light communication systems with DC-biased optical–orthogonal frequency-division multiplexing

In this article, a DC-biased optical–orthogonal frequency-division multiplexing visible light communication systems based on multi-point light-emitting diodes-array sources in the special-type vehicle is investigated. The novel lighting layout based on optical power evenly distribution principle is proposed to meet the desired lighting and communication requirement. Meanwhile, in order to resist the inter-symbol interference caused by multipath dispersion, DC-biased optical–orthogonal frequency-division multiplexing modulation strategy is suggested. The performance parameters of signal-to-noise ratio, the root-mean-square delay spread, and maximum transmission rate have been analyzed and calculated theoretically based on direct and multipath reflected channel models of visible light communication. The validity of the visible light communication system is demonstrated by simulation experiments results as follows: the received optical power range of −0.73 to 0.56 dBm in vehicle for approximately 2 m × 2 m × 1.5 m cube space, uniform illumination rate is 80.5%, average signal-to-noise ratio is 20.92 dB. Moreover, the maximum data rate can be improved from 107.8 to 477.4 Mb/s with the bit error rate at approximately 10−5, which meet the illumination and data transmission rate requirement for the special-type vehicle.

Multi-objective optimization of the heat transmission and fluid forces around a rounded cornered square cylinder

The unsteady fluid stream and warmth transmission nearby a square cylinder with sharp and rounded cornered edges are numerically examined, and then the roundness of the corner is predicted and optimized for the minimum fluid forces and maximum heat transmission rate. The roundness of the cylinder corner is changing 0.5D (circle) to 0.71D (square); D is the depth of the cylinder. The fluid flow and the heat transmission features around the sharp and curved cornered square cylinder are evaluated with the streamline, isotherm patterns, pressure coefficient, drag and lift coefficients, local Nusselt number (Nulocal) and average Nusselt number (Nuavg) at different Re and for several roundness values. These characteristics are predicted by the gene expression programming, and then the multi-objective genetic algorithm is utilized for the optimization. A number of combinations of values of corners have been found in the form of Pareto-optimal solution to compromise the minimum fluid forces with maximum heat transfer rate.

Wireless Multimedia Transmission Through Cooperative Spectrum Sharing With Quantized Feedback

A cooperative spectrum-sharing strategy is proposed for a hierarchical multimedia network consisting of a cellular base station transmitting high-priority (HP) data to a user equipment (UE) and multiple device-to-device (D2D) connection pairs which transmit low-priority (LP) signal to offload the cellular data traffic. In implementing the proposed strategy, the precoding design at each D2D transmitter is performed in such a way as to enhance the strength of the HP signal and minimize the interference caused at the UE by the D2D transmission. Furthermore, in accordance with the quantized signal-to-noise ratio (SNR) information reported by the UE for the cellular downlink, each D2D transmitter selects the power allocation factor which maximizes the D2D transmission rate while simultaneously satisfying the outage probability constraint for the HP signal. Having chosen the precoding vectors and power allocation factor for each D2D connection, the D2D transmitter which achieves the maximum D2D transmission rate is selected in a distributed manner via opportunity carrier sensing. The effectiveness of the proposed spectrum-sharing strategy is investigated by means of computer simulations. The results confirm that for most SNR regimes, the proposed strategy successfully meets the outage constraint on the HP signal while simultaneously maximizing the achievable rate of the LP signal.

A real signal and its states

The paper describes the general physical theory of signals, carriers of information, which supplements Shannon’s abstract classical theory and is applicable in much broader fields, including nuclear physics. It is shown that in the absence of classical noise its place should be taken by the physical threshold of signal perception for objects of both macrocosm and microcosm. The signal perception threshold allows the presence of subthreshold (virtual) signal states. For these states, Boolean algebra of logic (A = 0/1) is transformed into the “algebraic logic” of probabilities (0 ≤ a ≤ 1). The similarity and difference of virtual states of macroand microsignals are elucidated. “Real” and “quantum” information for computers is considered briefly. The maximum information transmission rate is estimated based on physical constants.

ISI-Avoiding Modulation for Diffusion-Based Molecular Communication

A molecular diffusion channel is a channel with memory, as molecules released into the medium hit the receptors after a random delay. Modulating over the diffusion channel is performed by choosing the type, intensity, or the released time of molecules diffused in the environment over time. Motivated by the desire to keep the encoder and decoder simple and the fact that channel state information is difficult to obtain in diffusion channels, we consider modulation schemes that avoid intersymbol interference (ISI), wherein molecules of the same type are released at time instances that are sufficiently far apart. This ensures that molecules of a previous transmission are faded in the environment, before molecules of the same type are reused for signaling. Avoiding ISI puts a constraint on the input sequence to the channel. In this paper, we study the fundamental limits on reliable communication rate, due to this constraint on input sequences. The maximum reliable transmission rate of ISI-avoiding modulations is given by the constrained coding capacity of the graph that represents the permissible transmission sequences. However, achieving the constrained coding capacity requires long blocklengths and delays at the decoder, making it impractical for simple nano-machines. The main contribution of this paper is to consider modulations with small delay (short blocklength) and show that they get very close to constrained coding capacity.

Distributed power allocation for spectrum sharing in mutually interfering wireless systems

Allocation of transmit power is critical for spectrum sharing and coexistence of mutually interfering wireless systems. In this paper we present a novel approach for allocation of transmit power, which is based on a non-greedy procedure that aims at maximizing transmission rate while also controlling interference levels. The proposed approach is fully distributed and requires no central control or coordination. Numerical results obtained from simulations are presented to illustrate the performance of the proposed approach in both sparse and dense environments. In sparse wireless environments, where there are fewer mutually interfering wireless links than available frequency bands, the proposed approach yields power allocations which outperform those obtained by applying alternative power allocation strategies, while in dense environments, where there are more interfering links than available frequency bands, the proposed approach yields power allocations with performance similar to those of existing power strategies. Thus, the distributed power allocation procedure based on the proposed approach is a drop-in replacement algorithm that yields better system throughput than existing algorithms for spectrum sharing.

Study on the color merging of white light and transmission properties of wavelength division multiplexing visible light communication system based on RGB light-emitting diodes

Visible light communication (VLC) systems have an advantage for simultaneously achieving communication and illumination. To strengthen the performance of VLC by using RGB light-emitting diodes (LEDs) while meeting the lighting requirements, the channel capacity and the transmission capability of the system are improved by utilizing the wavelength division multiplexing (WDM) technology. We make the chromaticity of the merged white light suitable for human eyes by the experiment. The parameters of merged white light based on RGB LEDs and the merging ratio data measured by the experiment are given. Hence, we study and analyze the eye diagrams and bit error rate (BER) of different optical channels. The simulation results show that maximum transmission rate of the output signal is up to 3.3 Gbit/s , and the BER is less than 10 −5 with a transmission distance of 2.5 m while meeting standard illumination requirements.

Layered Spatial Modulation for Multiuser Communications

A layered spatial modulation (LSM) scheme is proposed for the downlink of multiuser wireless communication systems. The proposed scheme falls in the class of the well-known point-to-point SM as it employs only one antenna in each transmission interval. However, it is designed based on assigning different sets of transmit antennas, rather than single antenna elements, to transmit different symbols of each user. We first study the error performance of the proposed LSM. In order to improve the overall error performance of the system, we employ a graphical approach to adaptively allocate antennas to different users. We also propose some techniques to increase the spectral efficiency of LSM. Extending the proposed method to the generalized LSM, we also compare the maximum transmission rate of the proposed scheme with that of the existing SM-based multiuser schemes, and show that this technique can significantly improve the spectral efficiency of the SM-based multiuser communications.

English

This paper aimed to evaluate the transmission of Fusarium oxysporum f. sp. vasinfectum (FOV) and the effects of this pathogen on the initial development of cotton plants following inoculation of seeds. Two cultivars (susceptible and resistant) and two strains (most and least aggressive) of the pathogen were used in this study. The inoculation method was based on the contact between seeds and fungal colonies on substrates containing mannitol. Percentage of FOV in seeds and the percentage of seed germination were evaluated by blother test and germination test, after inoculation. Emergence of seedlings and speed index, initial and final stands, size and dry weight of the plants were verified in trays containing soil substrate. Disease severity, pathogen transmission and plant infection, from seed to plant, were determined in separate trial on plants. Occurrence of the pathogen was higher when inoculum potential was increased for all variables analyzed. The number of normal seedlings, determined by seed germination test, decreased when the incidence of the pathogen in the seed was increased. The same occurred to other variables, in which there was difference between cultivars where IAC 20-233 presented the best performance. No significant differences were found between strains for emergence speed index, initial and final stands variables. Transmission and infection rates were increased according to the inoculum potentials increasing and the maximum pathogen transmission rate, from seed to plant was around 50%. Key words: Transmissibility, pathogenicity, fusarium wilt disease, cotton.

Sensing time optimization in energy-harvesting cognitive radio with interference rate control

In this paper, an energy-harvesting cognitive radio (CR) is considered, which allows the transmitter of the secondary user (SU) to harvest the primary signal energy from the transmitter of the primary user (PU) when the presence of the PU is detected. Then the harvested energy is converted into the electrical power to supply the transmission of the SU at the detected absence of the PU. By adopting the periodic spectrum sensing, the average total transmission rate of the SU is maximized through optimizing the sensing time, subject to the constraints of the probabilities of false alarm and detection, the harvested energy and the interference rate control. The simulation results show that there deed exists an optimal sensing time that maximizes the transmission rate, and the maximum transmission rate of the energy-harvesting CR can better approach to that of the traditional CR with the increasing of the detection probability.