2D Proactive Uplink Resource Allocation Algorithm for Event Based MTC Applications

We propose a two dimension (2D) proactive uplink resource allocation (2D-PURA) algorithm that aims to reduce the delay/latency in event-based machine-type communications (MTC) applications. Specifically, when an event of interest occurs at a device, it tends to spread to the neighboring devices. Consequently, when a device has data to send to the base station (BS), its neighbors later are highly likely to transmit. Thus, we propose to cluster devices in the neighborhood around the event, also referred to as the disturbance region, into rings based on the distance from the original event. To reduce the uplink latency, we then proactively allocate resources for these rings. To evaluate the proposed algorithm, we analytically derive the mean uplink delay, the proportion of resource conservation due to successful allocations, and the proportion of uplink resource wastage due to unsuccessful allocations for 2D-PURA algorithm. Numerical results demonstrate that the proposed method can save over 16.5 and 27 percent of mean uplink delay, compared with the 1D algorithm and the standard method, respectively.Comment: 6 pages, 6 figures, Published in 2018 IEEE Wireless Communications and Networking Conference (WCNC

Cooperative MIMO Communications in Wireless Sensor Networks: Energy Efficient Cooperative MAC Protocol

Multiple sensor nodes can be used to transmit and receive cooperatively and such a configuration is known as a cooperative Multiple-Input Multiple-Output (MIMO) system. Cooperative MIMO systems have been proven to reduce both transmission energy and latency in Wireless Sensor Networks (WSNs). However, most current work in WSNs considers only the energy cost for the data transmission component and neglects the energy component responsible for establishing a cooperative mechanism. In this work, both transmission and circuit energies for both components are included in the performance models. Furthermore, in previous work, all sensor nodes are assumed to be always on which could lead to a shorter lifetime due to energy wastage caused by idle listening and overhearing. Low duty cycle MAC protocols have been proposed to tackle this challenge for non-cooperative systems. Also in this work, we propose a new cooperative low duty cycle MAC protocol (CMAC) for two cooperative MIMO schemes: Beamforming (CMACBF) and Spatial Multiplexing (CMACSM). Performance of the proposed CMAC protocol is evaluated in terms of total energy consumption and packet latency for both synchronous and asynchronous scenarios. All the required energy components are taken into consideration in the system performance modeling and a periodic monitoring application model is used. The impact of the clock jitter, the check interval and the number of cooperative nodes on the total energy consumption and latency is investigated. The CMACBF protocol with two transmit nodes is suggested as the optimal scheme when operating at the 250 ms check interval with the clock jitter difference below 0.6Tb where Tb is the bit period corresponding to the system bit rate

A Survey of Low Duty Cycle MAC Protocols in Wireless Sensor Networks

22 page(s

MAC protocol for cooperative MIMO transmissions in asynchronous wireless sensor networks

Cooperative MIMO schemes can reduce both transmission energy and latency in distributed wireless sensor networks (WSNs). In this paper we develop a new Cooperative low power listening (LPL) Medium Access Control (MAC) protocol for two cooperative MIMO schemes: Optimal Beamforming (BF) and Spatial Multiplexing (SM). We develop analytical models for the total energy consumption and packet latency for both schemes and analyse the proposed MAC protocol in term of the total energy consumption and packet latency with imperfect synchronisation due to clock jitter. The impact of the clock jitter, the check interval and the number of cooperative nodes on the total energy consumption and latency are investigated. We observe that the Cooperative LPL MAC with Optimal BF is the most promising configuration and it is optimal when then number of co-operating nodes M=2 and jitter difference is below 0.6Tb

Compact Millimeter-Wave Bandpass Filters Using Quasi-Lumped Elements in 0.13-um (Bi)-CMOS Technology for 5G Wireless Systems

© 2019 IEEE.A design methodology for a compact millimeter-wave on-chip bandpass filter (BPF) is presented in this paper. Unlike the previously published works in the literature, the presented method is based on quasi-lumped elements, which consists of a resonator with enhanced self-coupling and metal-insulator-metal capacitors. Thus, this approach provides inherently compact designs comparing with the conventional distributed elements-based ones. To fully understand the insight of the approach, simplified LC-equivalent circuit models are developed. To further demonstrate the feasibility of using this approach in practice, the resonator and two compact BPFs are designed using the presented models. All three designs are fabricated in a standard 0.13- \mu \text{m} (Bi)-CMOS technology. The measured results show that the resonator can generate a notch at 47 GHz with the attenuation better than 28 dB due to the enhanced self-coupling. The chip size, excluding the pads, is only 0.096 \times 0.294 mm 2. In addition, using the resonator for BPF designs, the first BPF has one transmission zero at 58 GHz with a peak attenuation of 23 dB. The center frequency of this filter is 27 GHz with an insertion loss of 2.5 dB, while the return loss is better than 10 dB from 26 to 31 GHz. The second BPF has two transmission zeros, and a minimum insertion loss of 3.5 dB is found at 29 GHz, while the return loss is better than 10 dB from 26 GHz to 34 GHz. Also, more than 20-dB stopband attenuation is achieved from dc to 20.5 GHz and from 48 to 67 GHz. The chip sizes of these two BPFs, excluding the pads, are only 0.076\times 0.296 mm 2 and 0.096\times 0.296 mm 2, respectively.Peer reviewe

BER-delay characteristics analysis of IEEE 802.15.4 wireless sensor networks with cooperative MIMO

This paper presents a study of the impact of transmission delay differences between co-operating nodes on bit error rate performance and energy consumption of wireless sensor networks. We consider a wireless sensor network using an Alamouti virtual MIMO (multiple-input multiple-output) configuration between collaborating nodes operating in quasi-static Rayleigh flat-fading channels. Our results show that above certain delay difference (in the range above 0.75Tb), the traditional non-cooperative approach is more energy-efficient than the cooperative strategy and that the transmission delay difference has the most significant on the transmission energy consumption in the delay range of below 0.75Tb