Resource Auction Multiple Access Research Articles

A fair protocol for fast resource assignment in wireless PCS networks

Efficient sharing of communication resources is essential to PCS networks since the wireless bandwidth is limited. The Resource Auction Multiple Access (RAMA) protocol was recently proposed for fast resource assignment and handover in wireless PCS networks. The RAMA protocol assigns available communication resources (e.g., TDMA time slots or frequency channels) to subscribers one at a time using a collision resolution protocol based on subscriber ID's. However, the RAMA protocol encounters an unfairness problem; furthermore, performance results also indicate that it is inefficient at transmitting fixed-length subscriber ID's. Moreover, the emerging services such as teleconferencing have been presenting new challenges to dynamic-priority resource assignment. In this paper, we propose a modification to the RAMA protocol to improve its performance and resolve the unfairness problem. The proposed protocol also adopts dynamic priority assignment to improve the QOS for subscribers in overload environments.

Two Auction-Based Protocols for Fair and Fast Resource Assignment in Wireless PCS

The Resource Auction Multiple Access (RAMA) protocol was recently proposed for fast resource assignment in wireless PCS networks. The protocol assigns communication resources to subscribers using a collision resolution method based on subscriber ID‘s. In each auction cycle, the subscriber with the highest ID will obtain the resource. Thus the RAMA protocol encounters the unfairness problem since subscribers with lower ID‘s might be delayed forever. In this paper, we propose two modifications to the RAMA protocol to solve the unfairness problem. The first modification forces the RAMA protocol to process requests in bursts, i.e., new requests are not processed until the current burst of requests are all satisfied. The second modification asks the base station to select subscribers randomly instead of the one with the highest ID. We derive mathematical models to compare the performances of proposed and original protocols. Performance results indicate that the modification of random selection is fairer than other protocols in terms of the waiting time distribution.

A unified performance model for reservation-type multiple-access schemes

This paper presents a unified performance model for an integrated voice/data wireless system using reservation type multiple-access (MA) schemes. It is observed that although these schemes are different in the frame structure and resource assignment procedure, all of them can be described by several common state variables whose evolvement exhibits the Markovian property. Based on this observation, a general Markovian model is developed in this paper. Three performance measures, namely, voice-packet-loss probability, data throughput, and data delay are defined. As a special case, the performance evaluation model for the voice-only system is also presented. Numerical results are given and verified by simulation under both voice-only and integrated scenarios using packet-reservation MA (PRMA), dynamic time-division multiple access (D-TDMA), and resource auction multiple access (RAMA) as examples. It is found that our analytical model is quite accurate, especially in the region of interest. The impact of system parameters (such as the voice-permission probability, data-retransmission probability, maximum number of voice slots per frame, etc.) on the integrated system performance is also investigated for these three example systems.

Q-RAMA: QoS-guaranteed deterministicpacket access protocol in PCS networks

The RAMA (resource auction multiple access) protocol and its variations use a collision resolution protocol based on subscriber IDs to allocate available communication resources. However, these protocols suffer from unfairness or high packet dropping probability. The authors propose and analyse a novel deterministic packet access protocol, Q-RAMA, to improve the quality of service in PCS networks. Simulation results show that Q-RAMA has the lowest packet dropping probability and better overall performance.

Fair deterministic packet access protocol: F-RAMA(fair resource assignment multiple access)

The RAMA (resource auction multiple access) protocol uses a scheme where the access procedure is divided into fixed length cycles. A variation of RAMA, the tree-search resource auction multiple access (TRAMA) protocol, was proposed to reduce the length cycle. Both protocols present disadvantages, although different ones. The authors propose and evaluate another variation of RAMA, fair resource assignment multiple access (F-RAMA). Simulation methods were used to calculate packet dropping probability, access delay and statistics of speech clipping in voice transmission.

Dynamic Reservation Multiple Access (DRMA): A new multiple access scheme for Personal Communication System (PCS)

To improve the spectrum efficiency of integrated voice and data services in Personal Communication System (PCS), several reservation-type multiple access schemes, such as Packet Reservation Multiple Access (PRMA), Dynamic Time Division Multiple Access (D-TDMA), Resource Auction Multiple Access (RAMA), etc., have been proposed. PRMA uses the data packet itself to make a channel reservation, and is inefficient in that each unsuccessful reservation wastes one slot. However, it does not have a fixed reservation overhead and offers shorter access delay. On the other hand, fixed reservation overhead is unavoidable in both RAMA and D-TDMA. Compared to D-TDMA and PRMA, RAMA is superior in the sense that its slot assignment is independent of the traffic load. But its implementation is difficult. With these observations, a new reservation protocol, called Dynamic Reservation Multiple Access (DRMA), is proposed in this paper. With this new protocol, the success probability of channel access is greatly improved at the expense of slightly increased system complexity. It solves the problem of inefficiency in PRMA, but without introducing the fixed reservation overhead as in D-TDMA and RAMA. In addition, it is more suited to the dynamic behavior of the integrated traffic because there is no fixed boundary between voice and data slots (which is mandatory in D-TDMA and RAMA). Our numerical results indicate that its performance is superior to the existing reservation protocols, especially in the integrated traffic scenario. Moreover, the soft capacity feature is exhibited when the traffic load increases.

E-BAMA vs. RAMA /spl lsqb/multiple access protocols/spl rsqb/

The article presents a performance comparison of two random access protocols for wireless mobile signaling in which a single channel is dedicated to the signaling function, enhanced beacon assisted multiple access (E-BAMA) and resource auction multiple access (RAMA). Data traffic is transported separately on a set of orthogonal channels. The beacon assisted multiple access (BAMA) protocol was first presented as a method of providing mobility management functions, e.g., handover, while minimizing the processing burden placed on the mobile. In BAMA, throughout the duration of its call, an active user repeatedly and quasi-periodically broadcasts a beacon containing its ID using the Aloha protocol. Quasi-periodicity prevents a pair of users from repeatedly colliding with each other. When a base successfully receives the beacon and assigns a channel, it uses a separate downstream channel to send to the mobile an acknowledgement that contains the number of the assigned channel. The BAMA protocol includes a scheme to maintain lists of active mobiles in nearby cells and to exchange periodically these lists among the base-stations. The authors evaluate the capacity and delay performance of E-BAMA and RAMA. Then, they present a numerical comparison of the parameters. Finally, the results are summarized qualitatively. Some additional derivation is included in the appendix.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Resource auction multiple access (RAMA) in the cellular environment

Resource auction multiple access (RAMA) is a technique for rapidly assigning communication resources (e.g., TDMA time slots) in a wireless environment. This scheme is deterministic in that, barring errors caused by fading and noise, a resource assignment is made in each and every assignment cycle. Previous papers reported on the call assignment capacity of this technique and also demonstrated its capabilities for statistical speech multiplexing. In these studies, we used a selected set of GSM parameters while assuming perfect radio channel operation. In this paper, we extend the previous work in two directions: (1) we examine the effects of channel fading and noise; and (2) we consider both GSM and IS-54 cellular environments. Propagation is modeled, for purposes of this study, as flat Rayleigh fading, with mean propagation loss as a parameter. We focus on the subscriber-to-base link, which is most vulnerable to RAMA errors, and consider several forms of diversity at the base. We also consider two RAMA modes (call assignment only and statistical speech multiplexing). RAMA signaling is two-level amplitude shift keying (ASK). We show that a simple form of two-branch diversity can be very effective. Our final results show the probability of assignment error as a function of mean propagation loss for different diversities, systems, and average transmit powers. In IS-54, for example, simple diversity and an average transmit power of 100 mW yields error probabilities of 58 or less for losses as high as 154 dB. We also show that such error rates are more than adequate for purposes of call assignment. >

Resource auction multiple access (RAMA) for statistical multiplexing of speech in wireless PCS

The excess capacity of resource auction multiple access (RAMA), originally proposed for fast handoffs and resource allocations in wireless personal communications systems (PCS), is evaluated for statistical multiplexing of speech. Using selected GSM parameters in conjunction with M-ary FSK for signaling, it is shown that, in cells with propagation delays of up to 45 /spl mu/s, 216 assignments/s are feasible. The aim is to exploit this large assignment capacity to increase channel utilization. The authors show that, for packet dropping probabilities of 1%, RAMA can have a multiplexing gain as high as 2.63 with fast speech detection and 2.28 with slow speech detection. RAMA permits graceful degradation during peak traffic demand by operating at higher packet dropping probabilities. The authors also observe that, at low values of packet dropping probability, delays experienced by transmitted packets are more evenly distributed for the case of fast speech detection while the bulk of the packets experience less delay with slow speech detection. Speech clipping statistics associated with various values of packet dropping probabilities are also presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Distributed switching and control with fast resource assignment/handoff for personal communications systems

An architecture for a combined personal, mobile, and (possibly) loop access microcellular communications system in which calls are digitized and packetized is presented. A network of microcells is utilized to communicate with the various subscribers via radio. A fast handoff/resource assignment process is introduced. It is subscriber-controlled and is jointly performed by the subscribers and base station employing the resource auction multiple access (RAMA) algorithm. In this deterministic algorithm, resource utilization is independent of traffic load. Using selected GSM parameters with RAMA, for the purpose of illustration, it is shown that, in microcells with delays of 1 mu s, 1080 resource assignments per second are feasible: and with delays as high as 45 mu s, 216 assignments per second are feasible.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Speech multiplexing in wireless PCS employing resource auction multiple access (RAMA)

The excess capacity of the access mechanism in resource auction multiple access (RAMA) is evaluated for statistical multiplexing of speech. The aim is to exploit this excess capacity to increase the number of subscribers for a given bandwidth. It is shown that, for packet dropping probabilities of 1%, RAMA can have a multiplexing gain as high as 2.56 with cast speech detection and 2-2 with slow speech detection. The simulation results also indicate that RAMA is suitable for cast handoffs and resource allocation with statistical speech multiplexing over areas with a wide variety of cell sizes

Resource auction multiple access (RAMA): efficient method for fast resource assignment in decentralised wireless PCS

A novel method is presented to address the need for fast and flexible access, handoff, and resource assignment in future high capacity wireless personal communications systems (PCSs). In one deterministic algorithm, called resource auction multiple access (RAMA), fast handoff, access and resource assignments are incorporated. Resource use and throughput are unaffected by heavy traffic demand as in traditional contention schemes. Using selected GSM parameters with RAMA, it is shown that, in microcells with propagation delays of 1 μs, 2160 resource assignment/s are feasible. With delays of 25 μs, 648 assignment/s are feasible.