一种宽带零中频接收前端的设计

设计了一种宽带零中频解调接收前端,用于实现无人机通信系统高集成度和简化电路方案等。零中频接收前端在925～2 175 MHz载波频段上直接解调10 Mb/s码速率的偏移四相相移键控调制信号,适用于L、S频段的数据传输链路系统。零中频接收电路在10 MHz带宽时,动态增益范围可达到76 dB,射频信号接收灵敏度为-74 dBm。     

基于内积运算和正交矩阵的并行扩频传输新方案

为了提高并行解扩的频谱效率和功率效率,提出了以内积运算为数学理论基础,以线性算子扩频、结合律并行扩频传输、分配律并行解扩为特征的IOR并行扩频传输方案,较经典并行扩频相关解扩和经典并行扩频匹配滤波解扩的频谱效率和功率效率分别提高了2 096 128倍和1 048 576倍。在8×randn(1,length(b))干扰下,并行扩频传输64比特,其100 000次大样本检验结果表明统计平均误码率和标准差分别为0.000 0和0.000 7。     

δ/θ型基带相关检测/解扩方案

基于抗干扰的基本原理,提出了“相关解扩三要素”,从而形成了δ/θ型基带相关 解扩方案。其特点是：当经典基带相关解扩有效时,本方案同样有效;当经典失效时,本方 案仍部分有效。相关解扩的内核——相关函数的计算量减少了约99.61%,因而,较经典相 关解扩,以同一数量级提高了解扩的速率 和信道的利用率,减小了ASIC/数字集成化的面积,降低了成本,缓解了大容量高速率综合 业务扩频传输与扩频带宽及其电源的矛盾。     

宽带直扩信号的随机解调压缩采样方法

为了有效解决扩频测控通信系统宽带化带来的高速采样压力和高数据率问题,提出了基于压缩感知的直扩信号随机解调压缩采样方法。通过对模拟信号压缩采样原理进行研究,深入分析和推导随机解调采样原理及其数学模型,提出了基于压缩感知的直扩信号采集系统构架,并对压缩比取值影响因素进行了分析;给出了随机解调压缩采样系统硬件实现方案,并对其可行性进行了分析;最后对所提出的直扩信号压缩采样方法的性能进行了仿真分析。仿真结果表明,压缩采样系统可以实现直扩信号的压缩采样处理,并能够高精度重构原信号,但重构信号的解调门限会随压缩比增大而相应提高,这是采样率降低所需付出的代价。压缩采样为宽带直扩测控通信系统提供了一种高效的模数转换和同步解调处理思路。     

毫米波零中频全功率辐射计系统

提出了一种零中频接收的毫米波全功率辐射计系统,可降低外差式全功率辐射计系统实 现的难度和成本,有利于实现系统的集成化和轻小型化。运用随机过程理论分析了全功率辐 射计视频信号功率谱和温度灵敏度,在此基础上分析了零中频全功率辐射计的温度灵敏度。 结果表明,在满足截止频率高于1/2视频积分滤波器带宽条件下,零中频辐射计中频通道可 采用高通滤波器抑制直流漂移和低频噪声,而不会影响辐射计温度灵敏度,其理论值与射频带 宽2倍于中频带宽的全功率辐射计相同。完成了一个34～40 GHz毫米波多通道零中频全功率 辐射计系统的设计和研制,采用10通道一体化集成和本振空馈功率分配技术,实现了系统的集 成化和小型化,测试温度灵敏度与理论值相符,表明了理论分析的正确性和设计方法的可行 性。     

智能天线数字波束形成的LMS-DRMTCMA算法

本文提出一种适用于TD-SCDMA智能天线系统数字波束形成的LMS(最小均方)解扩重扩多目标恒模阵列(LMS-DRMTCMA)算法。该算法通过将Z.Rong等提出的LS解扩重扩多目标恒模阵列(LS-DRMTCMA)参考信号形成方法应用到LMS算法,并将TD-SCDMA标准提供的训练序列用于加速算法的收敛,使运算量远低于LS-DRMTCMA算法,明显低于导频LMS解扩重扩多目标阵列(LMS-DRMTA)算法。LMS-DRMTCMA算法还适用于激活用户数远大于天线阵元数的移动通信系统。仿真实验表明,LMS-DRMTCMA算法比LS-DRMTCMA算法和导频LMS-DRMTA算法具有更低的误码率,适合在极低信噪比环境中工作。LMS-DRMTCMA算法具有运算量低、易于实时实现的特点。     

适用于δ-相关解扩的扩频码检验方法

基于Welch内积定理（IC定理）,导出了归一化零时延互相关函数或零时延内积的绝对最大 值δ0 的三条基本特性,从而把Welch内积定理演变成了适用于计算量较小、解扩增益较高、有峰 值、无旁瓣的δ 相关解扩的扩频码检验方法,即“实用Welch内积定理-扩频码检验方 法 ”,为作者拟定的“δ/θ型基带相关检测/解扩方案”(电讯技术,2012,52(9)：1438 -1442)的工程应用奠定了扩频码检验与设计的理论基础。这两个检验方法与现存经典（含We lch）扩频码检验方法在参数、结构、判决方式等方面都不相同。     

基于δ匹配滤波器的扩频码同步门限检测方案

新近提出的δ相关检测/解扩方案,较经典相关检测/解扩方法在同步条件下其计算量减少了99.61%,抗干扰能力提高了2～3个数量级。然而,广泛应用的经典匹配滤波扩频码同步门限检测方法的计算量太大,抗干扰能力不足,当干扰较强时,难以提供有效同步扩频码序列。为了发挥δ相关检测/解扩方案的潜在抗干扰能力,提出了δ匹配滤波扩频码同步门限检测方案。仿真分析表明,所提方案较经典匹配滤波扩频码同步门限检测方法,计算量减小了99.61%,在输入SNR（－0～－20dB）＋sf256条件下,平均误同步率降低了1～2个数量级。     

δ/θ型相关解扩抑制多址干扰的能力分析

龙德浩、陈志清提出的δ/θ型基带相关检测/解扩方案(《电讯技术》2012年第9期1438 -1442页）,相对于经典相关解扩,其计算量减少了99.61%,且抗干扰能力较强,但定量分 析不足。鉴于此,基于大数定理,分别对VIVS准混沌、m和Walsh等3种扩频码阵列进行 了仿真相关解扩。结果表明：在给定AWGN条件下,当多址干扰分别为400条、350条和924条 时,δ/θ相关解扩较经典相关解扩的BER减小了2～3个数量级。     

零中频技术浅析

本文简要介绍了零中频技术的发展过程，并分析了零中频技术与超外差技术各自的优缺点。重点介绍了零中频技术在工程实践中的应用与实现，给出了零中频技术架构典型问题分析。     

直扩系统中数字匹配滤波器的设计仿真

主要讨论了量化比特数和取样间隔对数字匹配滤波器（DMF）解扩电路性能的影响，通过直扩系统（DSSS）的仿真结果表明；DMF的量化比特数取3时，量化误差可忽略不计（近似为无穷量化结果）；而在低抽样率下依靠DMF的样值序列前端处理（FEP）可以使系统误码率达到高抽样率的效果，而硬件代价却大大减小。     

短码、周期长码直扩信号伪码序列盲估计

针对短码、周期长码直扩信号在不同的时延下伪码序列估计问题,提出了一种基于奇异值分解的盲解扩算法。在已知信息码元速率和伪码周期条件的前提下,算法首先把接收到的直扩信号按照一定长度进行分段构成相关矩阵并对此矩阵进行奇异值分解得出信号子空间,然后根据信号子空间和伪码序列的模糊关系,利用求解的模糊酉矩阵和特定约束条件（如m序列）去其模糊性,最终估计出伪码序列。仿真结果表明,该算法不仅解决了在不同的时延下估计伪码序列带来的问题,而且具有稳定性高、在低信噪比条件下有良好的估计性能等优点。     

CONVEX RISK MEASURES FOR GOOD DEAL BOUNDS

We study convex risk measures describing the upper and lower bounds of a good deal bound, which is a subinterval of a no‐arbitrage pricing bound. We call such a convex risk measure a good deal valuation and give a set of equivalent conditions for its existence in terms of market. A good deal valuation is characterized by several equivalent properties and in particular, we see that a convex risk measure is a good deal valuation only if it is given as a risk indifference price. An application to shortfall risk measure is given. In addition, we show that the no‐free‐lunch (NFL) condition is equivalent to the existence of a relevant convex risk measure, which is a good deal valuation. The relevance turns out to be a condition for a good deal valuation to be reasonable. Further, we investigate conditions under which any good deal valuation is relevant.     

潜性与显性修辞原则：诚信与得体

修辞的原则是修辞界讨论较多的内容，但把修辞的原则分解为潜性原则和显性原则采讨论，尚不多见。修辞应该有潜性原则和显性原则之分。修辞的潜性原则是诚信，它是内在的，看不见，摸不着的；修辞的显性原则是得体，它是外在的，听得见，感受得到的。诚信是表达的出发点和落脚点。得体是诚信的结果和表现形式。诚信必须通过得体这个美丽的外衣来显现。但诚信和得体之问是非对称关系，因此，不可逆向推断。     

企业诊断的基础 自我评价模型

自我评价是一种诊断性评价 ,对于企业的持续改进和市场竞争力的提升具有非常重要的作用。模型的建立是任何类型评价进行的重要前提。因此 ,应建立一种自我评价模型 ,并从企业系统的各个方面对模型进行详细的说明 ,然后总结其主要特征。     

Merger and Innovation Incentives in a Differentiated Industry

This paper considers a duopoly with product differentiation and examines the interaction between merger and innovation incentives. The analysis reveals that a merger tends to discourage innovation, unless the investment cost is sufficiently low. This result holds irrespective of whether side payments between firms are allowed. When side payments between insiders within the merged firm are permitted, a standard result in the literature is reconfirmed, which suggests that a bilateral merger-to-monopoly is always profitable. When such side payments are not permitted, however, it is shown that a merger is not profitable when the efficiency of the new technology is relatively high and the investment cost is below a particular level.     

正义感：构建和谐社会的重要因素

正义感是人类以实现正义为目的的一种美好情感,是人的一种最基本的道德情操。一个以正义感调节的社会,人民幸福,社会稳定有序。和谐社会是一个制度正义的社会。制度正义既以正义感为前提,又以正义感为当然表征。因此,和谐社会亦是一个充满正义感的社会。在当前,正义感的培养显得格外重要和紧迫。对于道德教育来说,这既是挑战,又是机遇。     

营销的本质是管理交易而非买卖交易——兼论营销与销售的区别

"营销的本质"和"营销与销售的区别"是市场营销理论和实践的基本问题。从制度经济学的视角看,营销的本质是企业的一种管理交易,而不是产品买卖交易。营销具有管理交易的本质特征:生产性、效率性和层级性,而销售具有买卖交易的本质特征:分配性、价格性和平等性。营销本质上是生产者的行为,是产业资本的行为,而销售本质上是商人行为,是商业资本的行为。     

The effects of management succession in retail service banking

It is a fundamental tenet of modern management theory and practice that managers matter, and that a management change involving a transfer of authority will improve performance. In fact, there are two other possibilities, the management change may have no or even a negative effect. The purpose of this study is to examine the effects of a management change (succession) in the retail service branch banking context. The study is based on historical operational data and is longitudinal in nature. Specifically, the inter-relationships between pre-succession performance, predecessor tenure, reason for succession, origin of successor and organisational change were evaluated in 38 branches of a bank during a two-year period. The results indicated a strong association between pre- and post-succession performance, and that pre-succession performance is a predictor of successor origin, as is predecessor tenure which in turn influence post-succession performance.     

Understanding Participation

The word 'participation' is taken to refer to a situation in which employees have some sort of share in the businesses which employ them. On this basis a classificatory scheme is produced which distinguishes between different forms of participation as well as the sources and motives behind those different forms. Participation as a whole is then distinguished from bargaining between management and labour. In bargaining, separate and opposing interests are accepted. In participation, there is an attempt to produce an over-arching common interest. More importantly, bargaining operates outside those organizational arrangements definitive of a business which grant a strictly subordinate role to labour with respect to management structures and property entitlements. In contrast, participation is a modification of those arrangements up to, but not beyond, a position of equality for labour. It is this which gives participation its essentially reformist character and exposes it to attack from both those seeking a more than participatory share to labour and those for whom even a participating share is excessive.