Reader Anti-collision Protocol Research Articles

An Improved Approach for Reader Anti-Collision in Industrial Internet of Things

Radio-frequency identification (RFID) technology has been used in numerous applications, e.g., supply chain management and inventory control. This paper focuses on the practically important problem of reader-to-reader collision in large-scale RFID systems. There are many technical challenges during the existing work such as high computational complexity and low identification efficiency. To tackle the above challenges, this paper proposes a novel reader anti-collision protocol optimized by minimal reverse weight (NRA-MRW), which includes two phases. Extensive simulation results show that our proposed NRA-MRW can improve the identification efficiency and system throughput over the existing protocols by 25.2% and 12.3%, respectively.

Evaluation of Centralized Reader Anti-Collision Protocols for Mobile RFID System Based on Maximum Independent Set: A Simulation Study

Radio Frequency IDentification (RFID) systems often encounter reader collisions when multiple readers interrogate tags at the same time. Especially in the mobile RFID system, the mobility of readers leads to more reader collisions. To reduce reader collisions, some centralized reader anti-collision protocols have been developed through Time Division Multiple Access (TDMA), which allows readers to interrogate tags at different time slots. As an important branch of centralized reader anti-collision protocols, the Neighbor-Friendly Reader Anti-collision (NFRA) family is able to improve the throughput of mobile RFID networks with the assistance of the polling server. This paper explores the throughput (the number of readers interrogating tags simultaneously) of five NFRA protocols including the basic NFRA protocol and four variants by using the maximum independent set. Following the classical interference model, the interference between readers can be modeled as an undirected graph in which each maximum independent vertex set corresponds to one optimal reader anti-collision solution. The contribution of this paper is to establish an evaluation framework based on maximum independent set to evaluate the performance of reader anti-collision protocols. By considering the effect of the density of readers (low, medium and high density), three groups of simulations are arranged to test the effectiveness of the evaluation framework. In addition, the performances of five NFRA protocols in different dense reader environments are studied. Simulation results indicate that the proposed evaluation method based on the maximum independent set is effective and potential in evaluating different centralized reader collision protocols.

NFRA-AIC: A RFID Reader Anti-Collision Protocol With Adaptive Interrogation Capacity

In radio frequency identification (RFID) applications, multiple readers are deployed in the work area to improve their coverage. Such adjacent readers may be faced with reader collision due to their mutual interrogation interference. In this case, the performance of the RFID system will be degraded greatly. Therefore, some researchers proposed a number of the RFID reader anti-collision protocols, such as NFRA and its variants. Based on the technical framework of NFRA, this paper proposes an RFID reader anti-collision protocol with adaptive interrogation capacity (NFRA-AIC). The main contribution is that the interrogation time of a reader is determined by the number of tags within its interrogation region. Among NFRA-AIC, by adding sub-rounds and reserving a period of time between the AC signal and the first OC signal, readers that complete interrogating tags can release the communication resources allocated to them. Therefore, other adjacent readers can have a chance to use these released communication resources to interrogate tags. It is worth pointing out that those readers interrogating tags will not be interrupted by an AC signal. To evaluate the protocol performance, the proposed NFRA-AIC is compared with several protocols, i.e., DCS, PDCS, Colorwave, NFRA, NFRA-C, FRCA1, FRCA2, and BACP, in 12 scenarios. The simulation results show that the proposed NFRA-AIC protocol outperforms the other conventional protocols. Especially, the NFRA-AIC harvests the highest efficiency improvement of more than 110% under both the random and mobile deployment patterns compared to the latest protocol BACP.

A beacon analysis-based RFID reader anti-collision protocol for dense reader environments

Radio-frequency identification (RFID) is one of the major technologies for auto-identification in many applications. When multiple readers work together to improve the read rate and reliability, a dense RFID network is created. One of the most important issues to be considered in such environments is reader collision, which leads to reduced throughput. Although different schemes have been proposed to reduce reader collision, they often either require additional hardware or do not use network resources efficiently, or are not consistent with international laws and standards. In this paper, by managing and analyzing beacon messages, a new centralized scheme, which is consistent with European standards and laws, is proposed to reduce collisions and increase throughput. In the proposed scheme, by sending a priority code via a beacon message and making decisions based on the beacon messages received by readers, the available resources are used optimally, and the maximum number of readers is activated in one round. Additionally, in the proposed scheme, the priority code is initialized in such a manner that the readers access the channel fairly. The simulation results and comparison of the proposed scheme with other protocols indicate that throughput increased. Because of the increased throughput and fairness of the proposed scheme, the delay reduced compared with other schemes, and overall, the proposed scheme was superior to other centralized schemes.

Comparison of energy consumption for reader anti-collision protocols in dense RFID networks

Radio-frequency identification (RFID) is known as a universal technology and has been in the center of attention in the past few years. Readers and tags constitute the main parts of an RFID system. Similar to other wireless devices, RFID readers are confronted with the critical problem of collision. This is because in some applications, numerous readers are spread out densely and are attempting to attain the same tags simultaneously. Collisions are classified to reader-to-reader and reader-to-tag collisions. Both of these collisions may decrease the system’s throughput and performance, or even result in the consumption of a considerable amount of energy. Many various anti-collision protocols have been proposed to avoid these collisions, but there are only a few researches concerning their energy efficiency. While this paper will look at the main reader anti-collision protocols, it will also demonstrate the evaluation results of their energy efficiency via experimental simulations in similar circumstances. The obtained results can help in choosing the most efficient anti-collision protocol in applications like using mobile readers or combining RFIDs with WSN networks which have energy-consuming constraints.

New IoT proximity service based heterogeneous RFID readers collision control

Purpose Internet of Things’ (IoT’s) first wave started with tracking services for better inventory management mainly using radio frequency identification (RFID) technology. Later on, monitoring services became one of the major interests, including sensing technologies, and then more actuation for remote control-type of IoT applications such as smart homes, smart cities and Industry 4.0. In this paper, the authors focus on the RFID technology impairment. They propose to take advantage of the mature IoT technologies that offer native service discovery such as blutooth or LTE D2D ProSe or Wifi Direct. Using the automatic service discovery in the new framework will make heterogeneous readers aware of the presence of other readers and this will be used by the proposed distributed algorithm to better control the multiple RFID reader interference problem. The author clearly considers emerging Industry 4.0 use case, where RFID technology is of major interest for both identification and tracking. To enhance the RFID tag reading performance, collisions in the RFID frequency should be minimized with reader-to-reader coordination protocols. In this paper, the author proposes a simple distributed reader anti-collision protocol named DiSim that makes use of proximity services of IoT network and is compliant with the current RFID standards. The author evaluates the efficiency of the proposal via simulation. Design/methodology/approach In this paper, the author proposes a simple distributed reader anti-collision protocol named DiSim that makes use of proximity services of IoT network and is compliant with the current RFID standards. The author evaluates the efficiency of the proposal via simulation to study its behavior in very dense and heterogeneous RFID environments. Specifically, the author explores the coexistence of powerful static readers and small mobile readers, comparing the proposal with a standard ETSI CSMA method. The proposal reduces significantly the number of access attempts, which are resource-expensive for the readers. The results show that the objectives of DiSim are met, producing low reader collision probability and, however, having lower average readings per reader per time. Findings DiSim is evaluated with the ETSI standard LBT protocol for multi-reader environments in several environments with varied levels of reader and tag densities, having both static powerful RFID readers and heterogeneous randomly moving mobile RFID readers. It effectively reduces the number of backoffs or contentions for the RFID channel. This has high reading success rate due to the avoided collisions; however, the readers are put to wait, and DiSim has less average readings per reader per time. As an additional side evaluation, the ETSI standard LBT mechanism was found to present a good performance for low-density mid-coverage scenarios, however, with high variability on the evaluation results. Research limitations/implications To show more results, the author needs to do real experimentation in a warehouse, such as Amazon warehouse, where he expects to have more and more robots, start shelves, automatic item finding on the shelve, etc. Practical implications Future work considers experimentation in a real warehouse equipped with heterogeneous RFID readers and real-time analysis of RFID reading efficiency also combined with indoor localization and navigation for warehouse mobile robots. Social implications More automatization is expected in the future; this work makes the use of RFID technology more efficient and opens more possibilities for services deployment in different domains such as the industry which was considered not only in this paper but also in smart cites and smart homes. Originality/value Compared to the literature, the proposal offers the advantage to not be dependent on a centralized server controlling the RFID readers. It also offers the possibility for an existing RFID architecture to add new readers from a different manufacturer, as the readers using the approach will have the possibility to discover the capabilities of the new interaction other RFID readers. This solution takes advantage of the available proximity service that will be more and more offered by the IoT technologies.

NFRA-C, neighbor friendly reader to reader anti-collision protocol with counters for dense reader environments

In a dense and passive Radio Frequency Identification (RFID) network several readers are placed very close to each other for optimal connectivity and coverage. Such networks are susceptible to reader collision problems. In this paper, a novel and throughput efficient RFID reader׳s anti-collision protocol is proposed based on Neighbor Friendly Reader Anti-collision (NFRA) mechanism by revising its contention procedure to provide higher throughput in dense reader network. The behavior of the algorithm is evaluated through a set of simulation experiments which demonstrate that the algorithm is 15% more efficient than NFRA. Also, it has higher fairness as compared to NFRA and other state-of-the-art proposals.

Integrated reader and tag anti-collision protocol in RFID systems based on similar topology trees

This paper describes a new fast anti-collision algorithm for Radio Frequency Identification (RFID) systems. In this paper, an efficient protocol is introduced for anti-collision of tags and readers in multi-tag multi-reader environment. The proposed anti-collision protocol is based on constructing Similar Binary Trees Topology (STT) for all readers in the collision domain. The novelty of our protocol is the Parallel Binary Splitting (PBS) identification path that will be used in the tag identification process. All readers are synchronised to reply similar information and build similar binary trees topology. The identification time is divided among the tags and the readers. One bit reply will be sent sequentially (one-to-one bit dialog) in the identification process. The tags in the overlapped reader-region will be identified one time only. The integrated treatment of the collision problem provides minimum bit transmission with minimum overhead, higher throughput, and simple logic operation. Performed computer simulations have shown that the proposed collision recovery scheme is very fast and simple.

A Fair and High Throughput Reader-to-Reader Anticollision Protocol in Dense RFID Networks

Supply chain is a typical scenario of exploiting Radio Frequency Identification (RFID) technology. Its growing use in all the supply chain areas makes the presence of many close RFID readers more common. In such environment, interferences among readers are critical. Many protocols have been proposed to reduce reader-to-reader collisions. Experimental data showed that the Neighbor Friendly Reader Anticollision (NFRA) protocol (IEEE Trans. Ind. Electron., vol. 56, no. 7, pp. 2326-2336, July 2009) maximizes the network throughput. However, it does not take into account the delay between the request and the granting of query tags, causing delays for some readers. This paper proposes two approaches to increase the fairness and ensure a high throughput for each reader. A theoretical analysis, supported by experimental simulations, demonstrates the improvements achieved.

Reducing reader collision for mobile RFID

Mobile RFID, the technology of a cellular phone equipped with a RFID reader, allows users to read RFID tags anywhere. However, signals from more than two readers can interfere with one another, i.e., reader collision problem; reliable tag reading is necessary. This paper proposes GENTLE protocol to use beacon messages and multi-channel for increasing throughput. GENTLE protocol can also put tag ID information into the beacon message and share it among close readers. In addition, we suggest LSWBT protocol that reduces reader collision without beacon messages. Simulation results show that GENTLE and LSWBT protocols outperform existing reader anti-collision protocols.