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ReuseItems deposited in White Rose Research Online are protected by copyright, with all rights reserved unless indicated otherwise. They may be downloaded and/or printed for private study, or other acts as permitted by national copyright laws. The publisher or other rights holders may allow further reproduction and re-use of the full text version. This is indicated by the licence information on the White Rose Research Online record for the item. TakedownIf you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing eprints@whiterose.ac.uk including the URL of the record and the reason for the withdrawal request. Index Terms-M achine-to-machine, medium access control, cellular networks, Q-learning, ALOHA, RACH.I. INTRODUCTION ecent technological developments are changing the perception of wireless communication from the traditional human-centric view towards human independent communications. This is due to the increase in the number of devices that require connection to wireless networks. It has been argued in [1] that there are more electrical/electronic or mechanical objects in the world than people. It is estimated in [2], [3] that by 2020, up to 50 billion devices will require access to a communication network for industrial and domestic applications. This number is significant compared to the estimated human population of 8.3 billion. With this large difference in the ratio of the number of machines to humans, it will be difficult for such devices to be directly controlled by humans, and hence there is a need for them to communicate amongst themselves, with or without human intervention. This can be achieved through what is commonly referred to as Copyright (c) M2M communication will enable interaction between various devices with or without human intervention. M2M devices may be sensors, actuators, embedded processors, radio frequency identification (RFID) tags, smart meters, etc., [7]. The devices may be connected using wired or wireless access networks. Although wired networks are considered to be reliable and secure, they are very expensive to roll out and are not very flexible. As a result, many standards are not considering wired networks as an option for M2M communication. On the other hand, a wireless network is capable of providing excellent coverage, flexibility, mobility , and roaming capability. Hence, wireless access networks, which may be short range or long range (e.g. cellular), are considered as the most suitable option to deploy M2M communication [6].To realise cellular M2M communication, different wireless communication standardisation bodies , including 3GPP, are actively involved in research to provide global standards. Initial access to a cellular network is through the random access channel (RACH) which has a limited capacity. One of the majo r challenges identified by 3GPP in supporting M2M communication is the potential for RACH overload, due to the significant increase in traffic load that will arise from large numbers of M2M devices....

A common technique used by military to realize low probability of intercept (LPI) is linear frequency modulation (LFM) in the field of electronic intelligence (ELINT). This paper estimates the pulse width (PW) and the pulse repetition period (PRP) of LFM signal using instantaneous powers. The instantaneous powers were obtained either using time-marginal or power maxima approximated from a modified version of the Wigner-Ville distribution (WVD). The instantaneous power was also gotten directly from the signal by multiplication with its conjugate. Measurement was then carried out when the instantaneous power is ‘ON’ (the PW) and when it is ‘OFF’ (the PRP) at carefully selected thresholds. Thereafter, the mWVD-based algorithm was tested in the presence of additive white Gaussian noise (AWGN) at various signal-to-noise ratios. Results obtained during the test showed that the time marginal method emerged the best with minimum signal-to-noise ratio (SNR) of -5dB followed closely by the direct method with minimum SNR of -1dB at different thresholds. The results show that the proposed algorithm based on this modified WVD can be deployed in the practical field to determine radar’s performance and function

Abstract-In this paper, mathematical analysis supported by computer simulation is used to investigate the impact of both system and propagation loss parameters on the performance of cellular wireless network operating at microwave carrier frequencies greater than 2 GHz, where multiple tier of co-channel interfering cells are considered to be active. The two-slope path loss model and the uplink information capacity of the cellular network is used for the performance analysis. Results show that for carrier frequencies greater than 2 GHz and smaller cell radius multiple tier of co-channel interfering cells become active as compared to carrier frequencies lesser than 2 GHz. The multiple tier of co-channel interfering cells, leads to a decrease in the information capacity of the cellular wireless network. The results also show that the system performance is sensitive to most of the propagation model parameters such as the basic and extra path loss exponent.

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