بهبود عملكرد كانال دسترسي تصادفي شبكهLTEدر ارتباطات M2M

Optimizing the Performance of Random Access Channel of LTE Network in M2M Communications

سيستم‎هاي ماشين به ماشين براي رسيدن به هدف به‎وجود آوردن انقلابي در جهان آينده به‎وجود آمده اند كه دستگاه‎ ها را به يكديگر مرتبط مي كنند، به صورت هميشگي فعاليت مي كنند و اغلب بدون دخالت انسان مي توانند كاربرد هاي پيش بيني نشده‎اي را تسهيل كنند. M2M اساسا با ارتباطات انسان به انسان متفاوت است. اين تفاوت نيازمند تغييري در طراحي سيستم‎ هاي سلولي است وچالش هاي بسياري رادر بر دارد. يكي از آن ها مساله دسترسي به كانال تصادفي است در شرايطي كه تعداد بسيار زيادي ديوايس براي ارسال داده هاشان نياز به دسترسي به كانال دارند. پروژه مشاركتي نسل سوم GPP3 طرح بهبود هايي براي مكانيزم‎هاي دسترسي سيستم‎هاي سلولي تعيين كرد. بيش تر پيشنهادات موجود تنها روي افزايش تاخير دسترسي ناشي از تقاضا هاي دسترسي تعداد زياد ديوايس تمركز كرده است. در حالي كه، كارهاي تحقيقاتي بسيار كميبر مصرف انرژي دستگاه ‎ها انجام شده است.در اينمقاله روشي براي بهينه سازي مصرف انرژي ارايه شده وبا نرم افزار متلب شبيه سازي انجام و نتايجنشان مي دهد كه الگوريتم پيشنهادي كارايي انرژي كاربر ها رابه ميزان27 درصد به ازاي نرخ نيازمندي 2/0و 102 درصد براي نرخ نيازمندي 0.7 بهبود داده است.

MACHINE-TO-MACHINE (M2M) systems are deemed to create a revolution in our future world. Having devices connected to each other, operating in an autonomous manner, and with almost no human intervention, can facilitate the creation of unprecedented applications and new business models that can not be forseen today. The realization of this M2M system poses many challenges at various disciplines of the technology, ranging from computation, sensing, or energy harvesting technics, to communication technologies, among many others. The main mission of M2M networks is to connect, on the one side, a server running an application and processing data to make smart decisions( or to assist in the decision-making process) with, on the other side, an enormous amount of devices deployed in our world, interacting with the environment, with other machines, and with us. According to the European Telecommunications Standard Institute (ETSI) architecture, M2M devices and applications will be connected through the network domain. This includes the access and core networks and also M2M servers providing services and enabling applications. M2M are fundamentally different from human-based communications. This difference requires a mentality shift on the way that cellular systems are designed and include many challenges. Accessing to random channel is one of them when many devices request to access the channel to send their data. The 3GPPidentified the design of improvements for the access mechanisms of cellular systems when the number of subscribers raises up to tens of thousands per cells as a key challenge for next generations of networks. Firstly, present alternatives are classified and compared with each other, discussing the strengths and weaknesses of all of them. One of the main conclusions that can be drawn is that most of existing proposals only focus on the degraded access delay due to a high number of accessing devices. However, very few works have focused on the energy consumption of the devices, which may be a critical factor to facilitate M2M communications. In this work, a new technic is being proposed to optimize the energy consumption. This technic is being simulated by MATLAB software and results of simulation are being analyzed and discussed