Mobility Management for LTE-Advanced Relay Systems Research Paper

Mobility Management for LTE-Advanced Relay Systems - Research Paper Example These different technologies can cooperate together In order to improve the user’s quality of service and granting mobile users the ability of roaming across different wireless networks in a seamless manner. However, the different characteristics of each wireless technology with regards to QoS brought many challenges for provisioning the continuous services (e.g. audio/video streaming) in a seamless way. In such a heterogeneous environment, to support mobile user’s requirements, a mobility management mechanism is a key issue. Index Terms— Heterogeneous network, LTE-Advanced, Relay System, Vertical Handoff I. INTRODUCTION With the increase in demand and rapid development of wireless communication quality over the past 3 decades, the initial 1G has run into 4G with a high data rate and better mobility support. The 4G technique-International Mobile Telecommunications-Advanced (IMT-Advanced) systems include new capabilities that go significantly beyond those of the I MT-2000. Key requirements of the IMT Advanced systems, for instance, include improved mobility support and cell edge performance, increased spectral bandwidth and efficiency, reduced handover interruption time and reduced User plane latency and Control [1]. Considered as the main trend in future wireless communications, 3GPP LTE-Advanced has advanced features, for instance coordinated multipoint processing, carrier aggregation. It also considered as one of the top candidates towards achieving the IMT Advanced requirements. In 3GPP, high speed train scenario is agreed as the main scenario in Rel11 study item, mobile relay for E-UTRA. Here, when train rushes at a high speed the channel characteristics change and result in Doppler spread. Also the vehicles are vehicles are more crowded than other areas and therefore passengers are more likely to use high data rate services, for instance, browsing, playing games and watching videos so as to pass time [2]. The high data rate transmission requires strong signal strengths and high throughput, plus better mobility management, so mobile relay station for large vehicles are proposed for Broadband Wireless Access (BWA) system. A relay system may be mobile, which means it is a dedicated network node equipped on the vehicles to provide a fixed access link to those travelling on the vehicles. It is very suitable to solve the capacity gain of the high speed vehicles if it is well deployed. In a conventional cellular network, user equipment (UE) is connected directly to a Base Station (BS), and when a user moves away from the cell center, he/she will get less bandwidth which means lower data rates. However relaying technique has been introduced in 3GPP release 10 & 11 to allow establishing an indirect two-hop link between UE and BS through a Relay Node (RN). Relay nodes can also be used to spread out the cell coverage and increase the coverage outside main area (e.g. at cell edge). The two major challenges addressed in this c ontext are maintaining the throughput and ensure a seamless mobility and service continuity to all UEs. Hence, the objective of this paper is to develop, implement, and evaluate intelligent algorithms for next generation wireless communications systems with focus on throughput and service continuity. Specifically, the paper mainly addresses to the following aspects: Relaying in heterogeneous network, resources and mobility management. The rest of the paper is arranged as follows. Firstly, the overview of fixed and mobile relay system is given is Section II. In Section III, the paper presents a Handoff Analysis. Section IV presents a system level simulation and results. The paper concludes with section V. II. FIXED AND MOBILE RELAY SYSTEMS OVERVIEW A. Background

Culture Aspect of Childbirth and Parenting Essay

Culture Aspect of Childbirth and Parenting - Essay Example There are so many dimensions to it that studying its dynamics could provide deep insights for health care professionals. This paper will examine the case of child birth and care in Kalahari, South Africa. It is expected that the discourse can further highlight the argument that the idiosyncrasies in various culture are especially prominent in pregnancy, child birth and parenting and that an understanding of such could empower health care professionals to be effective especially in decision-making stage when working with a highly diverse population. Kalahari is a region in southern Africa that covers parts of South Africa, Botswana, Angola, Namibia, Zambia and Zimbabwe. The Bushmen have thrived in the region for at least 20,000 years. Children and parenting among them are treated much the same way in Western societies. Babies are indulged and cared for until their survival is ensured. Sigelman and Rider (2011) noted that â€Å"babies are touched 70% of daytime hours, are breast-fed w henever they want (usually 20-40 times a day), and may not be weaned until the age of 4.† (p. 124) The way mothers and families rear their young – with the attention and importance given to this enterprise - is fundamentally the same with how Western communities and families care for their children. They are loved, protected and provided for. The Bushmen, however, practices a unique birthing culture. A very important aspect of it is how the Kalahari women aspire and value the manner of giving birth to her child unaided. At least this has been true in the case of the Bushmen tribe of Ju|’hoansi. According to Selin (2009), this is quite common across this group because solitary child birth is widely seen as an opportunity to prove one’s worth as it is considered part of the rites of passage wherein women can display their ability for self-control, in addition to the ritualistic beliefs entailed in ethnic rites of passage. (p. 17) The implication of this cult ural practice is that it exposes mothers and infants to several risk factors; the most serious of these is death. This practice appears so different from the Western idea about the entire birthing process. In most western societies such as in the United States, pregnancy and child birth is an opportunity for family, relatives and friends to lend support. They are equated with the procreation processes and, hence, are extremely important for many individuals beyond the family. In addition, anthropologists consider kinship relationships in the West as fundamentally connected with acts of birth and human understanding of procreation. (Stone 2009) And so pregnancy and birthing are considered an event of extreme interest. Rites, beliefs, myths, among other cultural practices that our community have made all feature the requirement of support and closer ties. It is normal for us to see assistance, especially those by women who possess authoritative knowledge on the process, as one with gr eat survival value for birthing mothers. This is the reason why today both the health professional such as the doctor or the midwife are actual partners in the pregnancy and the birthing enterprise. Another interesting aspect about child birth in Kalahari is the environment. Desert covers much of the area and this claimed an important impact in the childbirth beliefs and behaviors of the Bushmen. Unlike in our society, for instance, the Bushmen did not have the luxury of water for birthing. Women