Wireless networks are founded on the principles of collision avoidance. This paper makes an attempt to detect and abort collisions in wireless networks. Briefly, the receiver uses physical layer information to detect collisions, and immediately notifies the transmitter to abort transmission. The collision notification consists of a unique signature, sent on the same frequency channel as the dat...

In this work we study the collision probability, saturation throughput and statistical delay for the carrier sense multiple access collision avoidance (CSMA/CA) protocol with request to send and clear to send (RTS/CTS) mechanism in the case of frequency channel division. We propose in this paper a modified version of CSMA/CA-RTS/CTS to be compatible with the channel repartition technique and we...

The interaction of laser pulses of picosecond duration and terawatt to petawatt power accelerated for the very fast undistorted plasma blocks for deuterium DD or deuterium tritium fast ignition is investigated. Based on the direct and instant conversion of laser energy into mechanical motion by nonlinear (ponderomotive) forces, any thermal pressure generation is delayed by the collision process...

Radio Frequency Identification (RFID) systems have emerged as popular and affordable solution for object identification in the recent years. One of the significant performance issues in these systems is to resolve the RFID Tag collision .Tag Collision happens when more than one tag reflect back a signal at the same time confusing the RFID reader. This collision disturbs the reader’s identificat...

A mixed algorithm based on tag estimation and tag identification is put forward by analyzing the collision problem and the anti-collision algorithm in RFID and combining the advantages of dynamic frame slotted ALOHA algorithm and dynamic binary search algorithm.

Tag collision has a negative impact on the performance of RFID systems. In this paper, we propose an algorithm termed anti-collision protocol based on improved collision detection (ACP-ICD). In this protocol, dual prefixes matching and collision bit detection technique are employed to reduce the number of queries and promptly identify tags. According to the dual prefixes matching method and col...

In passive RFID systems, tags are arbitrated on the Medium Access Control layer by the Framed Slotted Aloha protocol. Tags select an arbitrary slot to send their information, such that the reader receives slots with no responses, single tag responses or multiple tag responses, generating empty, singleton and collision slots, respectively. In order to maximize the system throughput, precise know...

This paper is devoted to hydrodynamic limits for collisional linear kinetic equations. It is a classical result that under certain conditions on the collision operator, the long time/small mean free path asymptotic behavior of the density of particles can be described by diffusion type equations. We are interested in situations in which the degeneracy of the collision frequency for small veloci...

In the paper, the ultrasonic sensor checking device union PLC communication function was introduced, which was applied to anti-collision protect system of multiple bridge cranes stride over the same rack in the railroad service workshop. The hardware and software system were designed which could communicate directly between FX2N series PLC and FREQROL series frequency transformers. PLC uses FX2...