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1.
Millimeter-wave (mmWave) is highly focused as a powerful mean enabling to perform very high data transmission. This paper proposes the enhancement of media access control (MAC) for the mmWave WPAN. The existing MACs have limits to achieve high data transmission over 1–2 Gbps by reasons of the low frame transmission efficiency and the high overhead of signal exchanges. In addition, the transmitting frames need to be protected in a poor channel condition for the high quality of service. The proposed MAC provides frame aggregation with unequal error protection (UEP) and block acknowledgment (Blk-ACK), which can solve the problems of the existing MACs and guarantee the high quality of service. Our theoretical throughput analysis shows that the proposed MAC does the high throughput enhancement compared to the existing MACs and achieves the MAC throughput over 2Gbps in the mmWave WPAN.  相似文献   

2.
Both IEEE 802.15.3c and IEEE 802.11ad standards define physical and medium access control layers for operation in the 60 GHz millimeter wave frequency band that is capable of multi-Gbps throughput. As both standards are used for multi-Gbps local communications, we would like to know which one is better for a given set of application domain requirements. In this paper, we compare the two standards qualitatively and quantitatively, focusing on multi-Gbps local communications. According to the quantitative performance analysis, both IEEE 802.15.3c and IEEE 802.11ad have almost the same performance in terms of throughput and delay. The qualitative comparison, however, shows that IEEE 802.11ad is more robust than IEEE 802.15.3c because the former has additional features of coexistence and backward compatibility.  相似文献   

3.
In this letter, we propose a three-dimensional Markov chain model for the 802.11e enhanced distributed channel access (EDCA) mode. This model can be used to compute the maximum sustainable throughput and service delay distribution for each priority class when under saturation load. The new framework models the performance impact of major quality-of-service (QoS)-specific features (e.g., CWMin, CWMax, AIFS, internal collision resolution) of the 802.11e EDCA mode, and hence can provide an analytical approach to pick the parameter values associated with EDCA to meet the QoS requirements of each priority.  相似文献   

4.
IEEE802.11e和IEEE802.15.3两个协议在当今无线网络中应用的十分广泛,在详细描述了两者的信道接入机制的基础上,对协议性能进行了分析对比,并指出了各自适用的范围.  相似文献   

5.
Sensor networks, in particular those used in embedded devices like robots, impose drastic temporal constraints and low-power consumption. The design of the physical layer and optimization of the medium access control are major keys for fulfilling these constraints. The low-power wireless personal area network IEEE 802.15.4 offers protocol and topology oriented toward this problem. However, several gaps have been identified, especially those concerning contention access phases and the lack of synchronization between star coordinators. To solve these issues, a new, fully deterministic access method has been developed, formally validated using Petri nets and quantitatively validated through a specifically-designed simulation tool. Researchers now have a real application for this newly designed protocol.  相似文献   

6.
Telecommunication Systems - This paper derives the outage and packet error probabilities of Non Orthogonal Multiple Access (NOMA) systems. In the first time slot, the Base Station transmits a...  相似文献   

7.
In this paper, the directional carrier sense multiple access/collision avoidance (CSMA/CA) protocol in the immediate acknowledgement mode for IEEE 802.15.3c is analyzed under saturation environments. For the analysis, a sensing region and an exclusive region with a directional antenna are computed probabilistically and a Markov chain model in which the features of IEEE 802.15.3c and the effects of using directional antennas are incorporated is analyzed. An algorithm to find the maximal number of concurrently transmittable frames is proposed. The system throughput and the average transmission delay are obtained in closed forms. The numerical results show the impact of directional antennas on the CSMA/CA media access control (MAC) protocol. For instance, the throughput with a small beamwidth of antenna is more than ten times larger than that for an omnidirectional antenna. The overall analysis is verified by a simulation. The obtained results will be helpful in developing an MAC protocol for enhancing the performance of mmWave wireless personal area networks.  相似文献   

8.
This paper evaluates throughput of IEEE 802.15.4 network under the interference of a saturated IEEE 802.11 network using an analytic method. Packet losses due to both collisions among IEEE 802.15.4 and mutual interference between IEEE 802.15.4 and 802.11 are considered for throughput analysis. To include the interference from IEEE 802.11, we modified the state transition probabilities of IEEE 802.15.4 two-state Markov process model. Simulation results closely match the theoretical expressions confirming the effectiveness of the proposed model.  相似文献   

9.
Wireless Networks - Hybrid duplex wireless networks, use half duplex (HD) as well as full duplex (FD) modes to utilize the advantages of both technologies. This paper tries to determine the...  相似文献   

10.
A large number of terminals transmitting data packets over a common radio channel to a central base station is studied. In inhibit sense multiple access (ISMA), the base station broadcasts a busy signal when an incoming packet is being received, to inhibit other terminals from colliding transmissions. This busy signal arrives at each terminal with a propagation delay, proportional to the distance between the base station and the terminal. This leads to unfairness in the probability of successfully transmitting a data packet, since nearby terminals have more up-to-date information on the actual channel status than remote terminals. This unfairness is additional to the advantage that nearby terminals have because of the capture effect, which is also considered. The paper applies nonstationary Poisson processes to describe the random arrivals of data packets at the central receiver. It is shown that the probability of a successful attempt to transmit a packet decreases, approximately linearly with the distance between the transmitter and the central receiver. The total throughput is also assessed, and it is found that the assumption of a fixed propagation delay adopted in CSMA studies by others gives too optimistic results for ISMA. Moreover, the analysis suggests a subtle change of the fixed delay approximation that enhances its accuracy, without adding complexity. The effect of propagation delays in random access radio networks are of increasing importance, since newly developed systems are designed to transmit with increasingly high bit rates  相似文献   

11.
The throughput of an FM mobile radio channel employing a nonpersistent multiple access protocol with inhibit sensing to provide packet data transmission is presented. With FM capture, the variations in received packet power due to propagation loss and multipath allow a packet to be successfully received in the presence of interfering packets, thus increasing the throughput over FM without capture.<>  相似文献   

12.
The IEEE 802.4 token bus standard defines an optional priority scheme to handle multiple classes of data. It allocates the channel bandwidth among different priority classes of messages by a set of timers at each station. An analytical model for the priority scheme is presented. The model relates the throughput of each priority class of messages to the traffic intensities of different classes, the target rotation times, and the high-priority token holding time. The network is assumed to be symmetric with respect to its parameters and the traffic distribution among nodes. Simulation results are used to evaluate the accuracy of the model. The model provides means of evaluating the network throughput and can be used to determine the time values to meet the throughput requirements of different classes of traffic  相似文献   

13.
MAC throughput limit analysis of slotted CSMA/CA in IEEE 802.15.4 WPAN   总被引:3,自引:0,他引:3  
  相似文献   

14.
Telecommunication Systems - Future wireless networks and 5G communication technology aims to provide seamless connectivity for geographical areas having thousands of users within hundreds of meter...  相似文献   

15.
An analysis is made of the throughput and delay performance of two classes of free-access tree algorithms with minislots. In one class, binary feedback information is available in minislots, and in the other, ternary feedback information is available. It is shown that the highest maximum throughput 0.56714 is achieved in the limiting case where the number of minislots in a (large) slot is infinity and minislot overhead is zero. A lower bound of the average transmission delays in these algorithms is analytically derived. The obtained lower bound is also a lower bound of the average delay of the whole class of the free-access algorithms  相似文献   

16.
Throughput and delay limits of IEEE 802.11   总被引:2,自引:0,他引:2  
The IEEE 802.11 protocol family provides up to 54-Mbps data rate, whereas the industry is seeking higher data rates. This paper shows that a theoretical throughput upper limit and a theoretical delay lower limit exist for the IEEE 802.11 protocols. The existence of such limits indicates that by simply increasing the data rate without reducing overhead, the enhanced performance, in terms of throughput and delay, is bounded even when the data rate goes into infinitely high. Reducing overhead is vital for good performance.  相似文献   

17.
Lim  D.M. Lee  H.S. 《Electronics letters》1991,27(20):1809-1810
The network throughput is analysed for the channel load sense multiple access with overload detection (CLSMA/OD) protocol in the spread spectrum packet radio networks. With threshold approximation for the channel capacity, the network is modelled as a discrete-time semi-Markov process. Various results are given which show the effects of the network parameters on the throughput.<>  相似文献   

18.
Throughput and energy consumption analysis of IEEE 802.15.4 slotted CSMA/CA   总被引:10,自引:0,他引:10  
Park  T.R. Kim  T.H. Choi  J.Y. Choi  S. Kwon  W.H. 《Electronics letters》2005,41(18):1017-1019
A new analytic model of the IEEE 802.15.4 slotted CSMA/CA is proposed, from which throughput and energy consumption are computed in saturation conditions. The analytic results are validated via ns-2 simulations.  相似文献   

19.
Designed for high data rate wireless personal area networks, the IEEE 802.15.3 medium access control (MAC) protocol fits well with emerging technologies like ultra-wideband. Peer discovery is essential in 802.15.3 piconets in which devices (DEVs) exchange MAC frames in a peer-to-peer manner. If two peer DEVs are unreachable, the standard peer discovery method will fail after unproductive backoff retransmissions, and a costly network layer routing is required. For DEVs uniformly distributed over the maximum coverage area of a piconet, such failures occur in up to 41.3% of intra-piconet peer discoveries. In this paper, we propose a novel third-party handshake protocol (3PHP) that provides more reliable and prompt peer discovery than the standard method. Especially, between directly unreachable DEVs within the same piconet, 3PHP replaces network layer routing by an efficient MAC layer forwarding that utilizes the available self-learning rate information to establish optimal routes. The mean peer discovery time for 3PHP is 100 μs lower than the standard method between directly reachable DEVs. More significantly, between directly unreachable DEVs within the same piconet, 3PHP has a much lower failure probability, and is up to 10 times faster than the standard method in establishing a peer-to-peer connection as the latter fails and network layer routing is invoked. Paper accepted for publication in ACM/Kluwers MONET. This paper is based in part on a paper presented at IEEE BroadNets 2005, Boston, MA, Oct. 2005.  相似文献   

20.
This paper develops a stochastic geometry‐based analytical approach for calculating the throughput reliability of a cloud‐radio access network (C‐RAN) comprising randomly distributed remote radio heads (RRHs) and randomly located users. A tunable distance‐based RRH transmit power control mechanism along with cooperative joint transmissions by the RRHs is employed to achieve power savings and high throughput reliability. The analytical result for the throughput reliability serves as input to analysis of per user achievable average rate and C‐RAN network‐level performance metrics of spectral efficiency and energy efficiency. The analytical results are validated by Monte Carlo simulation results with good agreement, thus confirming the accuracy of the developed analytical approach. The key finding from the analysis is that by carefully tuning the RRH transmit power and cooperation parameter (cluster radius), it is possible to realize a threefold improvement in the energy efficiency along with 108% enhancement in the spectral efficiency of C‐RANs. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

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