Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 132 for “"Channel conditions"”.
-
Radio-Location Techniques for Localization and Monitoring Applications. A study of localisation techniques, using OFDM system under adverse channel conditions and radio frequency identification for object identification and movement tracking
… angle-of-arrival estimation in a multipath channel with high levels of additive white Gaussian noise. A new methodology is interpreted over the multi carrier modulation scheme in which the simulation results of the estimated channel improves the performance of OFDM signal by mitigating the …
-
On Enabling Virtualization and Millimeter Wave Technologies in Cellular Networks
… and stochastic user equipment (UE) locations and channel conditions. Then, using the closed-form expression, we develop a sub-6 GHz virtual resource allocation framework that aggregates, slices, and allocates the sub-6 Ghz network resources to the virtual networks in such a way that the virtual …
-
Transmission of image data over digital networks involving mobile terminals
… because of the limited capacity of the mobile channels and the transmission errors caused by the multipath (Rayleigh) fading. In this research, transmission of line diagram images such as floor plans and street maps, over digital networks involving mobile terminals at transmission rates of 2400 …
-
Feasibility of a dynamic data rate satellite link for Inmarsat
… dynamic link improves the link by measuring channel conditions to determine the fastest data rate for successful communications. When channel conditions are good, the adaptive dynamic link will communicate at a high data rate, and when channel conditions are poor, the dynamic link will …
-
Simulation of VSELP speech encoder for mobile channels
… in terms of speech quality is done for different channel conditions using the BERSIM simulation tool. Simulations for realistic channel conditions were performed using the SIRCIM simulation tool. Quantitative results in the form of mean squared error and qualitative results in the form of speech …
-
Robust and efficient video/image transmission
… information transmission. The unreliability of channel conditions, limited channel bandwidth and explosive growth of information transmission requests, however, hinder its further development. Hence, research on robust and efficient delivery of video/image content is demanding nowadays. Three …
-
Joint source channel coding for progressive image transmission
… those embedded bit streams are very sensitive to channel noise and protections from channel coding are necessary. Typical error correcting capability of channel codes varies according to different channel conditions. Thus, separate design leads to performance degradation relative to what could be …
-
Performance evaluation of detection algorithms for MOMI OFDM systems
… will face a number of challenges from hostile channel conditions to interference from other users. This would result in an increase of detection complexity required for mobile systems. Complex detection will reduce the battery life of mobile devices because of the many calculations that have to …
-
Resource allocation and scheduling for communication satellites with advanced transmission antennas
… low-complexity on-line algorithm that considers channel conditions, interference and average delay constraints, and approaches the theoretical steady-state limit. We introduce optimized beam profiling based on traffic demand and channel conditions over satellite downlinks, which can achieve a …
-
Adaptation For Multi-Antenna Systems
… to adapt MIMO systems in the presence of varying channel conditions typically focus on characterizing the performance of a limited and predefined set of joint MoDem/CoDec and MIMO configurations over a representative set of channel realizations. Other work has attempted to adapt only the MIMO …
-
High-Performance Communication Protocols for Asynchronous Duty-Cycling Wireless Networks
… efficient packet delivery under dynamic channel conditions, and effective route discovery. This thesis presents a series of protocols to address these challenges. The first part of this thesis presents a new single-channel energy-efficient MAC protocol, called the Predictive-Wakeup MAC …
-
Efficient coding/decoding strategies for channels with memory
Many digital communication channels are affected by errors that tend to occur in bursts. A great deal of work has been devoted to finding good burst-error-correcting codes and developing burst-error-correcting schemes. However, burst-error-correcting codes are generally useless for long bursts. …
-
Spinal codes
… wireless networks to cope with time-varying channel conditions in a natural way, without requiring any explicit bit rate selection. The key idea in the code is the sequential application of a pseudo-random hash function to the message bits, to produce a sequence of coded symbols for …
-
On the Impact of Channel and Channel Quality Estimation on Adaptive Modulation
… has given rise to an increasing demand for channel capacity using limited bandwidth. Wireless channels vary over time due to fading and changing interference conditions. Typical wireless systems are designed by choosing a modulation scheme to meet worst case conditions and thus rely on power …
-
Opportunistic transmission scheduling for next generation wireless communication systems with multimedia services
… dynamically assigned data rates that match the channel capacity in order to improve the system throughput and overcome the problems associated with the location-dependent and time-dependent errors and channel conditions, the variable system capacity and the transmission power limitation. We …
-
A virtual flow meter to develop velocity-index ratings and evaluate the effect of flow disturbances on these ratings
… rating relates the mean velocity of the channel and an index-velocity calculated by averaging velocities measured at defined locations and sampling intervals. The application of velocity index ratings assumes that the relation between the measured index velocity and the mean velocity in a …
-
Adaptive radio resource management schemes for the downlink of the OFDMA-based wireless communication systems
… capacity. Thus, only those users with good channel conditions were considered for resource allocation and users in bad channel conditions were left out to starve of resources. The main objective of our study is to design adaptive radio resource allocation (RRA) algorithms that distribute the …
-
Channel Estimation Strategies for Coded MIMO Systems
… systems. In a multipath-rich wireless channel, deploying multiple antennas at both the transmitter and receiver achieves high data rate, without increasing the total transmission power or bandwidth. When perfect knowledge of the wireless channel conditions is available at the receiver, …
-
Dynamic power allocation and routing for satellite and wireless networks with time varying channels
… and wireless networks operate over time varying channels that depend on attenuation conditions, power allocation decisions, and inter-channel interference. In order to reliably integrate these systems into a high speed data network and meet the increasing demand for high throughput and low delay, …
-
Multi-dimensional direct-sequence spread spectrum multiple-access communication with adaptive channel coding
… systems. This scheme is known as adaptive channel coding, and gives a system the ability to firstly sense changes in conditions, and secondly, to adapt to these changes, exploiting the fact that under good channel conditions, a very simple or even no channel coding scheme can be used for …
Page 1 of 7