2009年移动通信世界大会在巴塞罗那举行

2月16日至19日，2009年移动通信世界大会在西班牙巴塞罗那举行。共有来自189个国家的4.7万名来宾参加了这一移动通信行业的顶级盛会。     

2011年移动世界大会五大看点

2011年移动世界大会（MobileWorldCongress，MWC2011）2月14日在西班牙巴塞罗那拉开大幕。作为移动通信产业全球范围内顶级的活动之一，MWC2011继续吸引了全球最重要的运营商、设备商、服务商，以及新型的移动互联网应用和运营公司、知名应用程序开发商参加。据此次会议主办方公布的数据，有超过190个国家的50000名移动通信领域高级管理人员参加此次大会。     

RANPLAN将参加2012年移动通信世界大会

由GSM协会主办的“移动通信世界大会”是全球最具影响力的、专注于移动通信领域的展览会之一。本届展会于2012年2月27日至3月1日在西班牙巴塞罗那举行。     

2013世界移动通信大会

世界移动通信大会（英文名：Mobile World Congress简称：MWC）是一年一度的行业大会，由移动通信亚洲大会发起，已经成为全球最具影响力的移动通信领域的展览会，由全球移动通信系统协会主办，最早于1995年在西班牙马德里举行，之后主办地曾一度移至法国戛纳，从2007年开始又回到西班牙巴塞罗那举行。     

MWC2010：移动应用战开打

2月1S日～18日，农历的正月初二至初五，当国人还沉浸在中国传统春节的喜庆和团圆气氛中时，由全球移动通信协会（GSMA）举办的2010年全球移动通信大会（Mobile World Confess 2010，简称MWC2010）却已经于西班牙巴塞罗那圆满落幕。以“美梦成真”为主题的本届大会共有1300多家企业参展，     

罗德与施瓦茨公司将参加2010年移动通信世界大会

在巴塞罗那举行的移动通信世界大会上,罗德与施瓦茨公司将完整地展示面向新的移动通信和无线技术的测试产品系列,再次彰显其在电子测试与测量领域的领先地位（一号厅,ID33号展台）。     

2011世界移动通信大会--杜比高清体验叩响全球移动市场

2011年2月14～17日,GSMA世界移动通信大会在西班牙巴塞罗那举办,位于Fira de Barcelona一号厅1C43号展位的杜比展台展出多款采用杜比技术的     

2009移动世界大会归来话感受

快速发展移动通信产业是应对全球经济危机的重要手段 2009年移动世界大会是在全球性经济危机的影响日益显现、社会各界对世界经济前景发展堪忧的大环境下召开的，吸引了移动通信产业相关领域的大量企业高层参与。移动通信企业的领袖们一致认为，推动移动通信产业的快速发展是当前应对全球经济危机的重要手段。     

触摸科技的魅力2008移动通信全球大会：移动世界大会创意纷呈

在2008年巴塞罗那的移动世界大会上，来自应用开发商的创意成为展场上的亮点。当前全球移动网络正在全面走向宽带化，这些创意为整个移动通信产业的发展注入了活力，为用户带来了新的通信体验。     

罗德与施瓦茨公司将参加2010年移动通信世界大会

在巴塞罗那举行的移动通信世界大会上，罗德与施瓦茨公司将完整展示面向新的移动通信和无线技术的测试产品系列（一号厅，1D33号展台）。无论是运营商还是设备制造业商，无论是LTE，HSPA＋，还是WiMAX技术，无论是研发过程中的射频、协议测试，一致性测试，生产测试还是网络优化，所有客户都能从R＆S公司找到满足各自需求的解决方案。     

MWC 2012：重新定义移动通信

全球移动运营商已经站到了业务发展的转折点上,开始了对于业务转型的实质性探索。2012年2月27日至3月1日,世界移动通信大会（Mobile World Congress 2012）如期在西班牙巴塞罗那召开。     

最小相关性和最大-最小相关性MWC重构算法

针对调制宽带转换器（Modulated Wideband Converter, MWC）现有重构算法高概率恢复所需的通道数高的问题,提出了MinCor(Minimum Correlation)算法和Max-MinCor(Maximum-Minimum Correlation)算法。MinCor算法利用噪声子空间与感知矩阵的最小相关性求支撑集。Max-MinCor算法联合利用信号子空间与感知矩阵的最大相关性和噪声子空间与感知矩阵的最小相关性求支撑集。实验结果表明,MinCor和Max-MinCor算法在理论条件下,重构所需的通道数均已接近理论极限值。MinCor算法可实现低通道数下的快速重构,但在信噪比小于10dB时,该算法的恢复性能下降;Max-MinCor算法在MinCor算法的基础上提高了抗噪性,但其重构速率低于MinCor算法。以上两种算法均可用于节约硬件成本、减少系统体积。      

ZTE Debuts LTE-A InterBand Dual-Carrier Commercial Base Station at MWC

ZTE debuted its LTE-A interband dual-carrier commercial base station at the Mobile World Congress2012(MWC2012)in Barcelona on February27,2012.The new     

Dynamic region‐based mobile multicast

Traditional mobile multicast schemes have higher multicast tree reconfiguration cost or multicast packet delivery cost. Two costs are very critical because the former affects the service disruption time during handoff while the latter affects the packet delivery delay. Although the range‐based mobile multicast (RBMoM) scheme and its similar schemes offer the trade‐off between two costs to some extent, most of them do not determine the size of service region, which is critical to the network performance. Hence, we propose a dynamic region‐based mobile multicast (DRBMoM) to dynamically determine the optimal service region for reducing the multicast tree reconfiguration and multicast packet delivery costs. DRBMoM provides two versions: (i) the per‐user version, named DRBMoM‐U, and (ii) the aggregate‐users version, named DRBMoM‐A. Two versions have different applicability, which are the complementary technologies for pursuing efficient mobile multicast. Though having different data information and operations, two versions have the same method for finding the optimal service region. To that aim, DRBMoM models the users' mobility with arbitrary movement directional probabilities in 2‐D mesh network using Markov Chain, and predicts the behaviors of foreign agents' (FAs') joining in a multicast group. DRBMoM derives a cost function to formulate the average multicast tree reconfiguration cost and the average multicast packet delivery cost, which is a function of service region. DRBMoM finds the optimal service region that can minimize the cost function. The simulation tests some key parameters of DRBMoM. In addition, the simulation and numerical analyses show the cost in DRBMoM is about 22∼50% of that in RBMoM. At last, the applicability and computational complexity of DRBMoM and its similar scheme are analyzed. Copyright © 2010 John Wiley & Sons, Ltd.     

Supporting dependable group‐oriented mobile transactions: redundancy‐based architecture and performance

Several of the emerging mobile commerce services, such as mobile auctions, mobile financial services, and multi‐party interactive games, will require support for dependable transactions. This is a difficult challenge because of both intermittent connectivity and potential failures in wireless infrastructure. In this paper, we present a multi‐network access‐based wireless architecture and related protocols to support dependable transactions. The key idea is to allow group users to utilize access to one or more wireless networks to complete different steps of a transaction. This allows for transactions to be completed even under time‐ and location‐dependent connectivity problems and network failures. The performance results show that access to multiple wireless networks leads to very high transaction completion probability even when individual wireless networks do not offer continuous and/or highly available access. The transaction completion probability is found to be dependent on the group size and number of steps in a transaction, and the same level of dependable performance for transactions can be achieved by increasing the number of wireless networks or improved access to individual networks. The overhead for multi‐network access can be further reduced by creating preferred wireless networks and by reducing the number of critical users in different transaction stages. Copyright © 2006 John Wiley & Sons, Ltd.     

CAPR: context‐aware participant recruitment mechanism in mobile crowdsourcing

With the advances of sensing, wireless communication, and mobile computing, mobile crowdsourcing has become a new paradigm for data collection and retrieval that has attracted considerable attention. This paper addresses the fundamental research issue in mobile crowdsourcing: Which participants should be selected as winners in each time slot with the aim of maximizing the total utility of the service provider in the long term? First, a double‐sided combinatorial auction model is introduced to describe the relationships between the mobile users and requesters from the perspective of supply and demand at a given time. Then, the coupling between the utility values of the system in different time slots is investigated. Based on the aforementioned analyses, this paper proposes a context‐aware participant recruitment mechanism, in which the mobile crowdsourcing system dynamically adjusts the participant recruitment mechanism depending on the ratio between the numbers of mobile users and requesters. Context‐aware participant recruitment consists of two main components: (1) a heuristic algorithm based on the greedy strategy to determine the winning participants and (2) a critical payment scheme, which guarantees the rationality of the proposed mechanism. Finally, extensive simulations demonstrate that the proposed mechanism achieves high system utility in the long term. Copyright © 2016 John Wiley & Sons, Ltd.     

基于随机投影思想的MWC亚奈奎斯特采样重构算法

针对现有调制宽带转换器（Modulated Wideband Converter,MWC）亚奈奎斯特采样重构算法性能不高问题,提出了一种基于随机投影思想的重构算法.该算法首先将MWC所获得的测量值矩阵通过随机投影方法压缩成具有较少向量的新的测量值矩阵,然后利用所提出的求解器求解多测量向量问题,通过检验和重复尝试性求解过程提高MWC的重构性能.从理论和实验两个方面验证了所提出的算法的有效性.实验结果表明,与著名的ReMBo算法相比,该算法有效提高了重构成功率;当信号的频带数相同时,精确重构所需的硬件通道数更小;在相同的硬件通道数前提下,可重构的信号频带数更高.该算法与ReMBo相比运算时间并没有大幅度增加,当信号频带数较大时,不仅重构性能高,而且运算时间比ReMBo小.     

Cuckoo: flexible compute‐intensive task offloading in mobile cloud computing

Mobile cloud computing (MCC) is an emerging technology to facilitate complex application execution on mobile devices. Mobile users are motivated to implement various tasks using their mobile devices for great flexibility and portability. However, such advantages are challenged by the limited battery life of mobile devices. This paper presents Cuckoo, a scheme of flexible compute‐intensive task offloading in MCC for energy saving. Cuckoo seeks to balance the key design goals: maximize energy saving (technical feasibility) and minimize the impact on user experience with limited cost for offloading (realistic feasibility). Specifically, using a combination of static analysis and dynamic profiling, compute‐intensive tasks are fine‐grained marked from mobile application codes offline. According to the network transmission technologies supported in mobile devices and the runtime network conditions, adopting “task‐bundled” strategy online offloads these tasks to MCC. In the task‐hosted stage, we propose a skyline‐based online resource scheduling strategy to satisfy the realistic feasibility of MCC. In addition, we adopt resource reservation to reduce the extra energy consumption caused by the task multi‐offloading phenomenon. Further, we evaluate the performance of Cuckoo using real‐life data sets on our MCC testbed. Our extensive experiments demonstrate that Cuckoo is able to balance energy consumption and execution performance. Copyright © 2016 John Wiley & Sons, Ltd.     

X‐Region: A framework for location privacy preservation in mobile peer‐to‐peer networks

While enjoying various LBS (location‐based services), users also face the threats of location privacy disclosure. This is because even if the communications between users and LBS providers can be encrypted and anonymized, the sensitive information inside LBS queries may disclose the exact location or even the identity of a user. The existing research on location privacy preservation in mobile peer‐to‐peer (P2P) networks assumed that users trust each other and directly share location information with each other. Nonetheless, this assumption is not practical for most of the mobile P2P scenarios, for example, an adversary can pretend to be a normal user and collect the locations of other users. Aiming at this issue, this paper presents x‐region as a solution to preserve the location privacy in a mobile P2P environment where no trust relationships are assumed amongst mobile users. The main idea is to allow users to share a blurred region known as x‐region instead of their exact locations so that one cannot distinguish any user from others inside the region. We propose a theoretical metric for measuring the anonymity property of x‐region, together with three algorithms for generating an x‐region, namely, benchmark algorithm, weighted expanding algorithm, and aggressive weighted expanding algorithm. These algorithms achieve the anonymity and QoS requirements with different strategies. Our experiments verify the performance of the algorithms against three key metrics. Copyright © 2013 John Wiley & Sons, Ltd.