Multimedia transmission is the effective way of transmitting multimedia elements (comprising voice, audio, video, data etc) from one place to the other via internet enabled protocols and other means. The term 'effective' is used because multimedia transmission is a nightmare if the conveyance is not smooth, seamless and efficient. Over time, the world has seen tremendous improvement that started from the era of the first generation of multimedia generation to the point of multimedia transmission. Much has been said and done in this area and the world has become a connected enterprise because of the transmission of multimedia. In spite of these successes that have been recorded in these areas, there are still many challenges facing multimedia transmission. What determines the progress of technology globally is the trends of evolution that multimedia transmission has gone through. An important challenge facing multimedia transmission is one that has been neglected for a long time. There has been deep neglect of the devices that are used in transmission while much emphasis has been on the protocols and the software that are being developed for multimedia transmission. Devices play a very important role in the realization of seamless transmission of media. Lately, the world seems to have realized the fact that devices that do the actual transmission needs more attention. These devices are the ones that do the distribution and the transmission of the multimedia streams or signals. This has been highlighted in a recent research study that was referenced in the Cambridge Handbook of Multimedia Learning that showed that the expectations of meeting the world's target on multimedia has been reduced by half because of problems arising from the inefficiency of multimedia devices and not really from the protocol perspective as earlier perceived. It is inline with the above that this research was titled "improving multimedia transmission through enhanced multimedia devices". Multimedia devices are the end to end units that are used in multimedia transmission. This research investigated the current devices that are being used, their deficiencies and the reasons that make them unstable for multimedia transmission. It focused on the real time multimedia transmission over the internet protocol (IP) through enhancing limited capabilities of the current multimedia devices. This will make way for new studies into newer devices that are better designed for the efficient multimedia flow. It will assure better quality end-to-end solutions in the area of multimedia distribution and transmission. This research is broad enough to cover most of the major areas of multimedia transmission and cut across several industries and technologies. These might include industries that specialize in internet telephony; design and manufacture multimedia devices and multimedia technologies. Despite the huge number of fields that this research cut across, the focus remained unchanged in highlighting this challenge and proffering a solution through enhanced end to end multimedia elements. It is hoped that this research work will contribute to the solution of this area of challenge and bring to fore the work that should be done in this regard. The advantages of improved multimedia transmission cannot be over emphasized as there will be a tremendous reduction in the cost of long distance communication globally and smoother media transmission which makes use of the readily available internet protocols. In spite of these successes that have been recorded in these areas, there are still many challenges facing multimedia transmission. What determines the progress of technology globally is the trends of evolution that multimedia transmission has gone through. An important challenge facing multimedia transmission is one that has been neglected for a long time. There has been deep neglect of the devices that are used in transmission while much emphasis has been on the protocols and the software that are being developed for multimedia transmission. Devices play a very important role in the realization of seamless transmission of media. Lately, the world seems to have realized the fact that devices that do the actual transmission needs more attention. These devices are the ones that do the distribution and the transmission of the multimedia streams or signals. This has been highlighted in a recent research study that was referenced in the Cambridge Handbook of Multimedia Learning that showed that the expectations of meeting the world's target on multimedia has been reduced by half because of problems arising from the inefficiency of multimedia devices and not really from the protocol perspective as earlier perceived. It is inline with the above that this research was titled "improving multimedia transmission through enhanced multimedia devices". Multimedia devices are the end to end units that are used in multimedia transmission. This research investigated the current devices that are being used, their deficiencies and the reasons that make them unstable for multimedia transmission. It focused on the real time multimedia transmission over the internet protocol (IP) through enhancing limited capabilities of the current multimedia devices. This will make way for new studies into newer devices that are better designed for the efficient multimedia flow. It will assure better quality end-to-end solutions in the area of multimedia distribution and transmission. This research is broad enough to cover most of the major areas of multimedia transmission and cut across several industries and technologies. These might include industries that specialize in internet telephony; design and manufacture multimedia devices and multimedia technologies. Despite the huge number of fields that this research cut across, the focus remained unchanged in highlighting this challenge and proffering a solution through enhanced end to end multimedia elements. It is hoped that this research work will contribute to the solution of this area of challenge and bring to fore the work that should be done in this regard. The advantages of improved multimedia transmission cannot be over emphasized as there will be a tremendous reduction in the cost of long distance communication globally and smoother media transmission which makes use of the readily available internet protocols. / Thesis (M.Ing. (Development and Management Engineering))--North-West University, Potchefstroom Campus, 2009.

This diploma thesis deals with the possibility of using HDLC (High-Level Data Link Control) protocol for communication and addressing of smart metering devices with a data concentrator. The HDLC protocol is used in two DLMS/COSEM (Device Language Message Specification/Companion Specification for Energy Metering) communication profiles. To simulate these communication profiles, the most appropriate simulation program is selected. Using this simulator, the first communication profile is implemented and the second one is designed. Communication profile based on TCP/IP (Transmission Control Protocol/Internet Protocol) has been fully implemented. To implement the three-layer HDLC communication profile, all options have been thoroughly explored. Using these findings, a process was designed to guide the full implementation. For the first communication profile the qualitative parameters are measured, which are then plotted and evaluated.

This thesis deals with the measurement of transmission parameters in the new generation access networks NGA. The aim of the thesis is to build and configure a test network and scenarios for the measurement of service quality parameters and then verify the transmission stability. The theoretical part describes general functioning of NGN networks, the requirements of different telecommunications services on quality parameters, methodology and recommendations for measuring transmission parameters in packet networks. The practical part deals with the configuration of scenarios using mainly MPLS technology and methodology of their testing. Measurements were performed according to recommendations IETF RFC 2544, IETF RFC 6349 with the ExacTCP test and ITU-T Y.1564 with the EtherSAM test. For measurements were used measuring instruments of EXFO brand. In conclusion, the measurement results according to the mentioned standards were evaluated and also the advantages of using the measurement according to the given standard in NGA access networks were discussed.

The thesis is focused on simulating of protocols from standard IEC 61850 in simulation tool OMNeT++. The theoretical part in the thesis deals with description of the field of operating technologies, supervisory control and data acquisition and protocols Tase-2/ICCP, IEC 61850, IEC 60870-5-104, DNP 3 and DLMS/COSEM. Next part deals with parameters influencing connection and description of simulation tools NS2/NS3, OPNET and OMNeT++. In the practical part there is created a network containing protocols from the standard IEC 61850 in the simulation program OMNeT++. Then in the network a end to end delay and packet loss with increasing traffic is measured.

Internet of Things(IoT) tillämpningar har ökat under de senaste åren och därför behövs nya kommunikationstekniker som uppfyller kriterierna låg strömförbrukning, lång räckvidd samt låg kostnad, som behövs för att distribuera tekniken i samhället. LoRa (Long Range) är en framstående trådlös kommunikationsteknik som utvecklades av LoRa Alliance för att uppfylla dessa kriterier.  Syftet med arbetet är att utveckla en mätmetod för prestandaanalys av radiosystemet LoRa. Mätmetoden används sedan för att analysera hur olika parametrar som datahastighet, avstånd och olika miljöer påverkar LoRa-nätverksprestandaparametrar dvs. signalstyrka, paketförluster, fördröjningar (latency) och fördröjningsvariationer (jitter).  För att uppnå syftet utvecklades först en mätningsmetod. Därefter genomfördes experiment i två olika miljöer (stadsmiljö och havsmiljö) för prestandaanalys av LoRa. I varje experiment positionerades en IoT-nod på olika avstånd och datapaket skickades med olika datahastigheter från IoT-noden till en gateway. Datahastigheten ändrades genom att ändra på spridningsfaktor (SF) och bandbredd. Passiv mätningsmetod användes för att samla in mätningsdata. Metoden som användes för att analysera resultaten var statistisk dataanalysmetod då de data som samlades in var kvantitativa.  Resultatet visar att signalstyrkan påverkas av miljö, avstånd och bandbredd. Signalstyrkan är starkare i fri sikt jämfört med stadsmiljö. Signalstyrkan är starkare även vid kortare avstånd och större bandbredd. Däremot har datahastigheten (SF) minimal påverkan på signalstyrkan. Att signalstyrkan påverkas av bandbredden är intressant resultat som inte kunde förutses innan. Paketförlusten påverkas av miljö, datahastighet (SF och bandbredd) och avstånd. Fler datapaket förloras vid längre avstånd och i stadsmiljön. Lägre datahastighet leder till att färre datapaket förloras och på så sätt längre kommunikationsräckvidd uppnås. Enligt tidigare arbetens simuleringar förutsågs att högre datahastighet leder till längre kommunikationsräckvidd men i den här studien genomfördes experiment på riktig hårdvara för att undersöka resultaten. Miljö, avstånd och datahastighet påverkar fördröjningen. Fördröjningen är några millisekunder längre i stadsmiljö än havsmiljö vid samma avstånd. Fördröjningen är även några millisekunder längre vid längre avstånd i samma miljö. Däremot har datahastighet största påverkan på fördröjningen. Fördröjningen ändras med några hundra millisekunder när datahastigheten ändras genom SF och/eller bandbredd.  Fördröjningsvariationen påverkas inte av miljö och avstånd. Datahastighet (bandbredd och SF) påverkar fördröjningsvariationen men denna påverkan är låg och man kan bortse från den. / The Internet of Things (IoT) use cases have increased significantly in recent years. Therefore, new wireless communication technologies are needed that meet the criteria such as low power consumption, long range and low cost. LoRa, which stands for "Long Range", is a wireless communication technology developed by the LoRa Alliance to meet these criteria.  The purpose of this paper is to a develop measurement method for performance analysis of the LoRa radio system. The measurement method used to analyze how different parameters such as data rate, distance and different environments affect LoRa network performance parameters i.e. signal strength, packet loss, latency and jitter. To achieve the purpose, a measurement method and prototype were first developed. Then experiments were carried out in two different environments (urban and open space). In each experiment, an IoT node was positioned at different distances and data packets were sent from the IoT node to a gateway with different data rates. The data rate was changed by changing the spreading factor (SF) and bandwidth. Passive measurement method was used to collect measurement data. The method used to analyze the results was the statistical data analysis method since the data collected was quantitative. The result shows that the signal strength is affected by the environment, distance and bandwidth. The signal strength is stronger in free view compared to urban environment. The signal strength is stronger even at shorter distances and greater bandwidth. However, the data rate (SF) has minimal impact on signal strength. The fact that the signal strength is affected by the bandwidth is interesting results that could not be predicted before. The packet loss is affected by the environment, data rate and distance. More data packets go lost at longer distances and in the urban environment. Lower data rate cause to fewer data packets go lost and a longer communication range being achieved. According to earlier work's simulations, it was possible to predict that higher data rates lead to longer communication range, but in this study experiments were carried out on real hardware to investigate the results. Environment, distance and data rate affect the delay. The delay is a few milliseconds longer in urban environment than the free space environment at the same distance. The delay is also a few milliseconds longer at longer distances in the same environment. However, data rate has the greatest impact on the delay. The delay changes by a few hundred milliseconds when the data rate is changed by SF and/or bandwidth. The jitter is not affected by the environment and distance. Data rate (bandwidth and SF) affects the delay variation but this influence is low and can be ignored.

Examensarbetet har utförts på uppdrag av företaget Seavus som såg ett behov avatt minska kabelanvändning i kontoret. Enhetsanvändning kan effektiviseras medhjälp av en central styrenhet, en så kallad smart hubb.Ett problem är att välja mellan Bluetooth och Wi-Fi för kommunikation mellan an-vändaren och den smarta hubben. Valet kan bero på flera faktorer som exempelvis,bandbredd (datahastighet), jitter (fördröjningsvariation) och paketförluster, vilkaär viktiga parametrar för att bedöma kvaliteten på kommunikationen.Plattformen Raspberry Pi tillsammans med kompatibel programvara användes föratt utföra prestandatester mellan Bluetooth och Wi-Fi i olika miljöer.Resultatet visade att Wi-Fi lämpar sig bäst för kommunikation med hög datahas-tighet och lågt jitter men där relativt hög grad av paketförlust är acceptabelt. Blue-tooth lämpar sig bäst för kommunikation med låg datahastighet, med högt jitteroch där det är viktigt att ha så låg paketförlust som möjligt. / This thesis has been carried out on behalf of the consulting company Seavus to re-duce cable usage in their office. Smart hubs (i.e. a central control unit) are made tomake usage of devices more effective.One problem is to decide between Bluetooth and Wi-Fi for communication betweenthe user and the smart hub. The choice may depend upon several factors such asbandwidth (throughput), jitter (variation in delay) and packet loss, which are im-portant parameters for assessing the quality of the communication channel.The HW-platform Raspberry Pi and compatible software was used as a measure-ment tool to test Bluetooth and Wi-Fi in different environments.The result showed that Wi-Fi is best suited for communication systems that requirehigh bandwidth and low jitter, and where high amount of packet loss is tolerable.Bluetooth is best suited for communication systems where low bandwidth and highjitter is tolerable, and minimal packet losses preferred.

Cloud gaming over mobile networks enables players to play high-resource consuming games on low-end devices with various intrinsic restrictions such as limited battery lifetime and computational capacity. For mobile cloud gaming(MCG), the remaining battery level on the device is one of the critical factors that affect the sensitivity of user satisfaction. Thus, an android application is developed to measure the energy consumption of mobile devices that measure the power consumption of the device such that the obtained values correspond with the specific network conditions and users. The collected values are studied to identify if the energy consumption of the device is impacted by the network degradation that might occur during MCG in cellular networks. Results demonstrate that the energy consumption is at its highest when packet loss is 45% at 2ms RoundTrip Time (RTT) delay. Moreover, a qualitative study on the perceived Quality of Experience (QoE) of MCG over mobile networks is conducted and its impact on the energy consumption of the device is investigated where 31 users play a cloud-based First Person Shooter (FPS) for approximately 2 hours each. The results demonstrate the existence of the relationship between energy consumption and perceived QoE whereas negates the hypothesis of the existence of the relationship between QoE and CPU resources. In addition, to make comparisons of energy consumption of MCG with online mobile gaming (OMG), another test is carried out where each user plays another non-cloud-based FPS game and it is found that MCG is more efficient than OMG under the least energy-consuming network condition (2ms RTT delay) by 33.3% and the most energy consuming network condition (45% packet loss at 2ms RTT) by 32.7% in 4G cellular network.

<p>This dissertation considers packet-switched wireless networks for transmission of variable-rate layered hybrid video streams. Target applications are video streaming and broadcasting services. The work can be divided into two main parts.</p><p>In the first part, a novel quality-scalable scheme based on coefficient refinement and encoder quality constraints is developed as a possible extension to the video coding standard H.264. After a technical introduction to the coding tools of H.264 with the main focus on error resilience features, various quality scalability schemes in previous research are reviewed. Based on this discussion, an encoder decoder framework is designed for an arbitrary number of quality layers, hereby also enabling region-of-interest coding. After that, the performance of the new system is exhaustively tested, showing that the bit rate increase typically encountered with scalable hybrid coding schemes is, for certain coding parameters, only small to moderate. The double- and triple-layer constellations of the framework are shown to perform superior to other systems.</p><p>The second part considers layered code streams as generated by the scheme of the first part. Various error propagation issues in hybrid streams are discussed, which leads to the definition of a decoder quality constraint and a segmentation of the code stream to transmit. A packetization scheme based on successive source rate consumption is drafted, followed by the formulation of the channel code rate optimization problem for an optimum assignment of available codes to the channel packets. Proper MSE-based error metrics are derived, incorporating the properties of the source signal, a terminate-on-error decoding strategy, error concealment, inter-packet dependencies, and the channel conditions. The Viterbi algorithm is presented as a low-complexity solution to the optimization problem, showing a great adaptivity of the joint source channel coding scheme to the channel conditions. An almost constant image qualiity is achieved, also in mismatch situations, while the overall channel code rate decreases only as little as necessary as the channel quality deteriorates. It is further shown that the variance of code distributions is only small, and that the codes are assigned irregularly to all channel packets.</p><p>A double-layer constellation of the framework clearly outperforms other schemes with a substantial margin. </p><p>Keywords — Digital lossy video compression, visual communication, variable bit rate (VBR), SNR scalability, layered image processing, quality layer, hybrid code stream, predictive coding, progressive bit stream, joint source channel coding, fidelity constraint, channel error robustness, resilience, concealment, packet-switched, mobile and wireless ATM, noisy transmission, packet loss, binary symmetric channel, streaming, broadcasting, satellite and radio links, H.264, MPEG-4 AVC, Viterbi, trellis, unequal error protection</p>

This dissertation considers packet-switched wireless networks for transmission of variable-rate layered hybrid video streams. Target applications are video streaming and broadcasting services. The work can be divided into two main parts. In the first part, a novel quality-scalable scheme based on coefficient refinement and encoder quality constraints is developed as a possible extension to the video coding standard H.264. After a technical introduction to the coding tools of H.264 with the main focus on error resilience features, various quality scalability schemes in previous research are reviewed. Based on this discussion, an encoder decoder framework is designed for an arbitrary number of quality layers, hereby also enabling region-of-interest coding. After that, the performance of the new system is exhaustively tested, showing that the bit rate increase typically encountered with scalable hybrid coding schemes is, for certain coding parameters, only small to moderate. The double- and triple-layer constellations of the framework are shown to perform superior to other systems. The second part considers layered code streams as generated by the scheme of the first part. Various error propagation issues in hybrid streams are discussed, which leads to the definition of a decoder quality constraint and a segmentation of the code stream to transmit. A packetization scheme based on successive source rate consumption is drafted, followed by the formulation of the channel code rate optimization problem for an optimum assignment of available codes to the channel packets. Proper MSE-based error metrics are derived, incorporating the properties of the source signal, a terminate-on-error decoding strategy, error concealment, inter-packet dependencies, and the channel conditions. The Viterbi algorithm is presented as a low-complexity solution to the optimization problem, showing a great adaptivity of the joint source channel coding scheme to the channel conditions. An almost constant image qualiity is achieved, also in mismatch situations, while the overall channel code rate decreases only as little as necessary as the channel quality deteriorates. It is further shown that the variance of code distributions is only small, and that the codes are assigned irregularly to all channel packets. A double-layer constellation of the framework clearly outperforms other schemes with a substantial margin. Keywords — Digital lossy video compression, visual communication, variable bit rate (VBR), SNR scalability, layered image processing, quality layer, hybrid code stream, predictive coding, progressive bit stream, joint source channel coding, fidelity constraint, channel error robustness, resilience, concealment, packet-switched, mobile and wireless ATM, noisy transmission, packet loss, binary symmetric channel, streaming, broadcasting, satellite and radio links, H.264, MPEG-4 AVC, Viterbi, trellis, unequal error protection

The aim of this thesis is to optimize the design of the Fat-IBC-based communication of a novel neuroprosthetic system in which a brain-machine interface is used to control a prosthetic arm. Fat-based intra-body communication (Fat-IBC) uses the fat tissue inside the body of the bearer as a transmission medium for low-power microwaves. Future projects will use the communication system and investigate ways to control the prosthetic arm directly from the brain. The finished system was able to individually control all movable joints of multiple prosthesis prototypes using information that was received wirelessly through Fat-IBC. Simultaneous transmission in the other direction was possible, with the control data then being replaced by sensor readings from the prosthesis. All data packets were encoded with the COBS/R algorithm and the wireless communication was handled by Digi Xbee 3 radio modules using the IEEE 802.15.4 protocol at a frequency of 2.45 GHz. The Fat-IBC communication was evaluated with the help of so-called "phantoms" which emulated the conditions of the human body fat channel. During said testing, packet loss measurements were performed for various combinations of packet sizes and time intervals between packets. The packet loss measurements showed that the typical amount of transmitted data could be handled well by the fat channel test setup. Although the transmission system was found to be well-functioning in its current state, increasing the packet size to achieve a higher granularity of the movement was perceived to be viable considering the findings from the packet loss measurements.