Wireless communication techniques for indoor positioning and tracking applications

Magdeburg, Univ., Fak. für Elektrotechnik und Informationstechnik, Diss., 2010

Providing QoS for publishing/subscribe communication in dynamic ad-hoc networks

QoS, MANET, Ad-hoc networks, Simulation, wireless communication

middleware for cooperating mobile embedded systems

Mobile embedded systems, wireless communication, real-time systems, real-time scheduling, communication protocols, cooperation, reliability and fault-tolerance, middleware

Implementation of Reed-Solomon RS (255,239) Code

In this paper the construction of Reed-Solomon RS(255,239) codeword is described and the process of coding and decoding a message is simulated and verified. RS(255,239), or its shortened version RS(224,208) is used as a coding technique in Low-Power Single Carrier (LPSC) physical layer, as described in IEEE 802.11ad standard. The encoder takes 239 8-bit information symbols, adds 16 parity symbols and constructs 255-byte codeword to be transmitted through wireless communication channel. RS(255,239) codeword is defined over Galois Field GF and is used for correcting upto 8 symbol errors. RS(255,239) code construction is fully implemented and Simulink test project is constructed for testing and analyzing purposes.

High-speed UDP Data Transmission with Multithreading and Automatic Resource Allocation

In this paper a utilization of the high data-rates channels by threading of sending and receiving is studied. As a communication technology evolves the higher speeds are used more and more in various applications. But generating traffic with Gbps data-rates also brings some complications. Especially if UDP protocol is used and it is necessary to avoid packet fragmentation, for example for high-speed reliable transport protocols based on UDP. For such situation the Ethernet network packet size has to correspond to standard 1500 bytes MTU[1], which is widely used in the Internet. System may not has enough capacity to send messages with necessary rate in a single-threaded mode. A possible solution is to use more threads. It can be efficient on widespread multicore systems. Also the fact that in real network non-constant data flow can be expected brings another object of study –- an automatic adaptation to the traffic which is changing during runtime. Cases investigated in this paper include adjusting number of threads to a given speed and keeping speed on a given rate when CPU gets heavily loaded by other processes while sending data.