The efficiency of tag identification in an RFID (radio identification system) can be low down due to the tag collision problems. The tag collision problem occurs when a reader try to read multiple tags in an interrogation zone. As a result, the reader doesn’t identify the tag correctly. That causes a loss of information or data interference. To solve such kind of issues a series of ALOHA based ...

We present time-parallel algorithms for parallel simulation of multiple access protocols for medium access – in particular, slotted Aloha and slotted -persistent CSMA. Two mechanisms are presented — regeneration point-based and fix up-based. Aloha is simulated using both mechanisms and CSMA is simulated using only the first mechanism. An analytical technique is developed to predict speedup for ...

The problems of identifying a set of tagged objects simultaneously in an RFID network have hampered the adoption of RFID universally. When multiple tags transmit their IDs in a single period of time to a single reader over a shared wireless channel, the tag signals may collide. This collision will disturb the reader’s identification process. Hence, we proposed a modified version of Accelerated ...

Slotted Aloha is an effective random access protocol and can also be an important element of more advanced media access protocols. This paper investigates slotted Aloha in a radio environment with multiple access points. Specifically, we examine the impact of multi-access-point (multi-AP) diversity on the performance of slotted Aloha. The paper considers both omni-directional (OM) and beamformi...

An exciting application of Multi-hop Packet Radio Networks (MPRNet) is to provide communication services in environments without suitable infrastructure. One key design issue in MPRNet is the formulation of Medium Access Control (MAC) protocols. In this paper, the performance of two MAC protocols, Slotted ALOHA (S-ALOHA) and Spatial TDMA (S-TDMA), are investigated. In many MPRNet, the traffic l...

We consider the problem of stability of slotted ALOHA for a system consisting of N users communicating with a common receiver, which employs spatial diversity to receive multiple transmissions simultaneuosly. We introduce a general packet reception model to incorporate multiple packet receptions since the collision channel model is no longer valid in such a scenario. We characterize the stabili...

We propose a model of price formation in Double Auction markets which employs the strong simplifying assumption that agents neglect strategic feedback effects and regard themselves as playing a Game against Nature. Agents otherwise are strict expected utihty maximizers employing Bayesian updating procedures. We prove the optimality of simple (‘aggressive reservation price’) strategies in our ge...

An exciting application of Multi-hop Packet Radio Networks (MPRNet) is to provide communication services in environments without suitable infrastructure. One key design issue in MPRNet is the formulation of Medium Access Control (MAC) protocols. In this paper, the performance of two MAC protocols, Slotted ALOHA (S-ALOHA) and Spatial TDMA (S-TDMA), are investigated. A finite number of buffered n...

 This paper presents an analysis of the performances of the Aloha protocol combined with the preamble sampling technique. This protocol is intended for low power sporadic communications in an Ad Hoc wireless network of sensors. The delay performances and the resulting power consumption and lifetime are computed analytically. The benefits of using CSMA instead of Aloha are indicated. The lifeti...

In this paper, a simple frame size adjustment of dynamic framed slotted Aloha for tag identification in RFID networks is proposed. In dynamic framed slotted Aloha, the reader is required to announce the frame size for every frame. To achieve maximum system efficiency, it is essential to set the frame size according to the number unidentified tags appropriately. The proposed approach utilizes th...