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Impects of Channel Characteristic and Brand Equity on Consumers BehaviorYang, Pei-Ya 24 June 2010 (has links)
With the prosperity of economy, the increase of national income, and the improvement of living standards, female consumers¡¦ requirement of underwear are changing gradually from the function of simple cover and warmth to the pursuit of fashion and self-expression. As a result, we can see the underwear market has a substantially growth in the recent years. When observing the market activities, we found that the branches opened one after another. The underwear industry continues to develop. In this study, we took ¡§EASY SHOP¡¨, the sub brand of Audrey Taiwan, as an example to discuss the effects between channel characteristic and brand equity, and then to see if the latter would affect consumer¡¦s behavior. Furthermore, we regard channel characteristic as independent variable, brand awareness, brand loyalty, perceived quality, brand association and brand image as intervening variables, and finally consumer characteristic as moderating variable to discover the impact on consumer behavior. The purposes of this study are as following¡G1. To discuss the degree of effect on brand equity which caused by channel characteristic. 2. To study the degree of effect on brand equity which caused by consuming behavior. 3. To exam the degree of moderate on consuming behavior caused by consumer characteristics. Our target interviewers are female consumers that have visited ¡§EASY SHOP¡¨ and bought underwear by themselves. Through the questionnaire analysis, we are intent on understanding the views of consumers. And also, we use SPSS to conduct the analysis process to see if channel characteristic and brand equity have an impact on consumer behaviors. We found that¡G1. The service quality of Physical channel are more reliable by consumers. 2. Channel characteristic has an impact on brand image and brand association. 3. Brand equity has an impact on consuming behavior. 4. Brand loyalty has a deeper impact on consumer behavior. 5. Consumer characteristic has moderating effect on underwear consuming behavior.
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A Simulator for analyzing the throughput of IEEE 802.11b Wireless LAN SystemsVasudevan, Srinivasan 11 February 2005 (has links)
Wireless Local Area Networks (WLAN) have proliferated in the last 5 years. The IEEE 802.11b products have become commonplace both in the residential and business places for untethered Internet access. However the end user experience has often been less satisfactory than what the technology can offer. The degradation in the performance of the system is mainly attributed to the poor network design. The current network design is primarily RF centric. There are two factors that need to be in the incorporated in the design. Firstly a clear understanding of the traffic sources in the network such as the peak load of the system is necessary. Secondly the design should account for the limitations of the indoor propagation such as interference and multipath.
The goal of this thesis is to develop a simulator which will predict the performance (throughput) of an end user. The throughput is predicted for a given topology and traffic source. The simulator is built on object oriented design. To validate the simulator a measurement campaign was conducted. The campaign was conducted in two different channel conditions, office space and open hall. The channel measurements were also performed at these locations to understand the multipath.
Comparative studies indicate that the choice of the rate adaptation algorithm hugely influences the predicted throughput. The simulator results match very well with the measurement results for the open space scenario. For the office space scenario the simulator varied by roughly 20% from the measurement results. This was due to existence of multipath leading to Inter Symbol Interference. / Master of Science
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Multirate MC-CDMA:performance analysis in stochastically modeled correlated fading channels, with an application to OFDM-UWBKunnari, E. (Esa) 20 May 2008 (has links)
Abstract
Multicarrier and multiple input–multiple output (MIMO) techniques have become popular in wireless communications over multipath fading channels in recent years. This thesis firstly considers the characterization and simulation of fading mobile radio channels for MIMO multicarrier systems. Secondly, the performance of spread-spectrum multicarrier (MC) code-division multiple-access (CDMA) with multirate transmission is analyzed. Thirdly, the analysis is applied to ultra-wideband (UWB) orthogonal frequency-division multiplexing (OFDM) systems enhanced with frequency-domain code-division multiplexing (CDM).
The response of a small-scale fading channel is derived as a function of time, transmit and receive antenna positions, and subcarrier frequency, which leads to a tapped delay-line model with time-, space-, and frequency-selective taps. The taps are modeled as a sum of a deterministic line-of-sight or dominant scattered path and a zero-mean Gaussian part composed of a number of unresolvable scattered paths and, therefore, are Rice fading. The Gaussian parts have the desired temporal and spatiospectral correlations generated by time-correlation shaping filtering and a space-frequency correlation transformation, respectively. The simulator achieves a good accuracy while retaining a reasonable computational complexity.
The generic performance analysis of MC-CDMA includes both the multicode and variable spreading factor (VSF) multirate schemes that are inherent for CDMA and capable of providing efficient support for services of different required data rates. The analysis also takes into account the intersymbol interference caused by the multipath delay components exceeding a guard interval, which is commonly omitted in the literature by assuming the guard interval to be longer than the maximum delay spread. Results comparing and pointing out notable differences in the error rate performance of the two multirate schemes in conjunction with six different combining techniques are presented for a synchronous downlink and both a synchronous and asynchronous uplink.
The analysis of CDM-enhanced OFDM-UWB involves first a single piconet with different combinations of the VSF and multicode schemes. Frequency-domain spreading is found to improve the performance remarkably when a sufficient spreading factor and a suitable subcarrier combining method are used. Subsequently, CDMA of simultaneously operating piconets (SOPs) with either the VSF or multicode scheme is considered. While both multirate schemes result in a similar performance when the number of SOPs is large, notable differences arise when there are only a few SOPs.
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Feasibility Study and Performance Evaluation of Vehicle-to-Everything (V2X) Communications ApplicationsChoi, Junsung 13 September 2018 (has links)
Vehicular communications are a major subject of research and policy activity in industry, government, and academia. Dedicated Short-Range Communications (DSRC) is currently the main protocol used for vehicular communications, and it operates in the 5.9 GHz band. In addition to DSRC radios, other potential uses of this band include Wi-Fi, LTE-V, and communication among unlicensed devices. This dissertation presents an architecture and a feasibility analysis including field measurements and analysis for vehicle-to-train (V2T) communications, a safety-critical vehicular communication application. The dissertation also presents a survey of research relevant to each of several possible combinations of radio-spectrum and vehicular-safety regulations that would affect use of the 5.9 GHz band, identifies the most challenging of the possible resulting technical challenges, and presents initial measurements to assess feasibility of sharing the band by DSRC radios and other devices that operate on adjacent frequencies using different wireless communication standards.
Although wireless technology is available for safety-critical communications, few applications have been developed to improve railroad crossing safety. A V2T communication system for a safety warning application with DSRC radios can address the need to prevent collisions between trains and vehicles. The dissertation presents a V2T early warning application architecture with a safety notification time and distance. We conducted channel measurements at a 5.86–5.91-GHz frequency and 5.9-GHz DSRC performance measurements at railroad crossings in open spaces, shadowed environments, and rural and suburban environments related to the presented V2T architecture. Our measurements and analyses show that the DSRC protocol can be adapted to serve the purpose of a V2T safety warning system.
The 5.9 GHz band has been sought after by several stakeholders, including traditional mobile operators, DSRC proponents, unlicensed Wi-Fi proponents and Cellular-Vehicle-to-Everything (C-V2X) proponents. The FCC and National Highway Traffic Safety Administration (NHTSA), the two major organizations that are responsible for regulations related to vehicular communications, have not finalized rules regarding this band. The relative merits of the above mentioned wireless communication standards and coexistence issues between these standards are complex. There has been considerable research devoted to understanding the performance of these standards, but in some instances there are gaps in needed research. We have analyzed regulation scenarios that FCC and NHTSA are likely to consider and have identified the technical challenges associated with these potential regulatory scenarios. The technical challenges are presented and for each a survey of relevant technical literature is presented. In our opinion for the most challenging technical requirements that could be mandated by new regulations are interoperability between DSRC and C-V2X and the ability to detect either adjacent channel or co-channel coexisting interference. We conducted initial measurements to evaluate the feasibility of adjacent channel coexistence between DSRC, Wi-Fi, and C-V2X, which is one of the possible regulatory scenarios. We set DSRC at Channel 172, Wi-Fi at Channel 169 for 20 MHz bandwidth and at Channel 167 for 40 MHz, and C-V2X at Channel 174 with almost 100% spectrum capacity. From the measurements, we observed almost no effects on DSRC performance due to adjacent channel interference. Based on our results, we concluded that adjacent channel coexistence between DSRC, C-V2X, and Wi-Fi is possible.
DSRC systems can provide good communication range; however, the range is likely to be reduced in the presence of interference and / or Non-Line-of-Sight (NLoS) conditions. Such environmental factors are the major influence on DSRC performance. By knowing the relationship between DSRC and environmental factors, DSRC radios can be set up in a way that promotes good performance in an environment of interest. We chose propagation channel characteristics to generate DSRC performance modelling by using estimation methods. The conducted DSRC performance measurements and propagation channel characteristics are independent; however, they share the same distance parameters. Results of linear regression to analyze the relationship between DSRC performance and propagation channel characteristics indicate that additional V2T measurements are required to provide data for more precise modeling. / PHD / Researchers and regulators in industry, government, and academic institutions are interested in vehicular communications. Dedicated Short-Range Communications (DSRC) is currently the standard protocol for communication between vehicles, including for safety applications, and operates in the band of radio frequencies near 5.9 GHz. In addition to operators of DSRC radios, other potential users are interested in using the 5.9 GHz band. This dissertation presents an architecture and a feasibility analysis including field measurements for vehicle-to-train (V2T) communications, a safety-critical vehicular communication application. The dissertation also identifies major technical challenges that could become important in the future for users of the 5.9 GHz band. The challenges will be different depending on what decisions government regulators make about the types of radios and communication protocols that are allowed in the 5.9 GHz band and about which types of radios should be used for vehicular safety.
Although wireless technology is available for safety-critical communications, few applications have been developed to improve railroad crossing safety. To prevent collisions between trains and vehicles, we present a vehicle-to-train (V2T) communication system that uses DSRC radios to provide safety warnings to motorists. Although the term V2T is used, the emphasis is on communication from the train to vehicles. We present a high-level design, or architecture, of the warning system that includes goals for safety notification time and vi distance. We conducted measurements of radio channels near 5.9 GHz as well as measurements of 5.9 GHz DSRC radio link performance at the same locations (railroad crossings in open spaces, shadowed or obstructed environments, and rural and suburban environments). The measurements were performed to help decide whether the V2T warning system architecture would work.
A DSRC system can provide good communication range; however, that range could be reduced if the DSRC system experiences interference from other radios or if the signal is partially blocked due to objects between the DSRC radios. The environmental factors are the most important influence on DSRC performance. By knowing the relationship between DSRC and environmental factors, manufacturers and operators can set up the radios to perform well in environments of interest. Although DSRC performance and radio channel characteristics were measured separately, they were measured in the same locations near railroad crossings. This made it possible to perform a statistical analysis of the relationship between DSRC performance and propagation channel characteristics. This analysis indicated that additional measurements will be required to collect enough data to develop robust statistical models that relate DSRC performance directly to measured channel characteristics. However, the results of the V2T measurements that we conducted near rural and suburban railroad crossings with varying numbers and types of obstacles to the radio signals provide a strong indication that DSRC can be used for to provide V2T safety warnings.
The 5.9 GHz band has been sought after by several stakeholders, including traditional mobile operators and others who support use of the band for DSRC, unlicensed Wi-Fi, and CellularVehicle-to-Everything (C-V2X) communication. The FCC and National Highway Traffic Safety Administration (NHTSA), the two major organizations that are responsible for vii regulations related to vehicular communications, have not finalized the rules regarding this band. The relative merits of the above mentioned communication standards and coexistence issues between these standards are complex. There has been considerable research devoted to understanding the performance of these standards, but in some instances there are gaps in needed research. We have analyzed regulation scenarios that FCC and NHTSA are likely to consider and have identified the technical challenges associated with these potential regulatory scenarios. The technical challenges are presented and for each a survey of relevant technical literature is presented. In our opinion for the most challenging technical requirements that could result from new regulations are interoperability between DSRC and C-V2X and the ability to detect either adjacent channel or co-channel coexisting interference. We conducted initial measurements to evaluate the feasibility of adjacent channel coexistence between DSRC, Wi-Fi, and C-V2X, which is one of the possible regulatory scenarios. From the measurements, we observed almost no effect on DSRC performance when other types of radios used frequencies adjacent to the frequencies used by the DSRC radios. Based on our results, we concluded that adjacent channel coexistence between DSRC, C-V2X, and Wi-Fi is possible.
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Showrooming : Samband mellan kanalattribut, produkttper och friåkningbeteendet showrooming / Showrooming : A study in what engages consumers in this shopping behaviourSandberg, Sophie, Källdén, Elin January 2017 (has links)
Problemställning: Konsumentbeteendet showrooming är ett hot mot den fysiska butikens kundlojalitet. För att företag med fysiska butiker ska kunna bemöta detta beteende i deras lojalitetsarbete behöver de veta vad som får konsumenter att engagera sig i detta beteende och varför. Syfte: Syftet med studien är att bidra till förståelsen för showrooming genom att undersöka hur olika kanalattribut och produkttyper driver ett urval svenska konsumenter till att engagera sig i showrooming. Forskningsfråga: Vilka olika kanalattribut och produkttyper leder till att urvalet av konsumenterengagerar sig i showrooming? Vilka kanalattribut respektive produkttyper har störst påverkan på deras engagemang i showrooming? Resultat: Urvalet engagerade sig i showrooming och deras beteende påverkades av kanalattribut och produktkategorier men på olika sätt. Vidare visade det sig att vissa av attributen och produktkategorierna inte alls ledde till att urvalet engagerade sig i showrooming. Kunskapsbidrag: Denna studie har bidragit med kunskap om friåkningsbeteendet showrooming genom att bidra med kunskap om vilka kanalattribut och produktkategorier som får konsumenter att engagera sig i detta shoppingbeteende och varför / Problems: The consumer behaviour called showrooming is a threat towards the customer loyalty of the physical store. In order for these companies to great this behaviour in their loyalty work they need to know what leads to consumers engaging in this behaviour and why Purpose: The purpose of this study is to contribute to the understanding of showrooming through an investigation about how different channel attributes and product types leads a selection of Swedish consumers to engage in showrooming. Research question: Which different channel attributes and product types leads to the selection of Swedish consumers engaging in showrooming? Which channel attributes and product types have the biggest impact on the consumers engagement in showrooming? Result: The selection engaged in showrooming and their behaviour was affected by channel attributes and product categories, however, differently. Furthermore, it became visible that some channel attributes and product categories did not lead towards consumers engaging in showrooming. Knowledge contribution: This study has contributed with knowledge about the phenomena showrooming through contribution of what channel attributes and product categories leads towards consumers engaging in this consumer behaviour.
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