基于LLR近似算法的星座重排高级混合ARQ

本文研究了采用16-QAM调制和星座重排的chase合并型高级混合ARQ系统.针对星座重排中比特可靠性的差异.提出一种近似算法逼近软解调输出比特的对数似然比.仿真结果表明,该近似算法能有效降低重传后比特可靠性的差异,且计算复杂度大大降低,提高了系统的性能.     

基于ATMEGA64L和TRH031M的RFID读卡器设计

基于ATMEGA64L微控制器和TRH031M读卡芯片设计了工作频率为13.56MHZ的RFID读写器系统,把RFID技术应用到物流系统中.     

Cofinal elementary extensions

We investigate some properties of ordered structures that are related to their having cofinal elementary extensions. Special attention is paid to models of some very weak fragments of Peano Arithmetic.     

Generalized pressure-volume equations mimicking the Stacey reciprocal K-primed equation of state

Two generalized polynomial expressions, one based on a logarithmic form and the other on an exponential form have been set up that give pressure-volume (P-V) relationship and higher derivative properties mimicking the Stacey reciprocal K-primed equation of state. The results have been obtained for pressure P, bulk modulus K and its pressure derivative K′ for six metals viz. Ag, Al, Au, Cu, Mo and W at different values of compression down to V/V₀=0.5. The zero-pressure values of input parameters K₀ and have been taken from the literature, whereas and have been fixed to match the Stacey reciprocal K-primed equation. The polynomial equations thus formulated can be used as a substitute for the Stacey equations of state (EOS) for determining P-V relationship and higher derivative properties such as K and K′.     

一种ZigBee电力无线抄表数据收发终端设计

为了解决ZigBee无线抄表系统数据采集发送集成度不高、设备繁琐等问题,通过对ZigBee无线标准协议的研究和对当前无线抄表系统实现过程的分析,设计出一种基于ZigBee的电表数据收发终端。该终端主要是将MCU系统和RFCC2430无线射频芯片相结合,包括数据接收、无线数据发送和电源三个硬件电路部分,完成对电表数据的接收和无线发送,重点阐述该终端节点的硬件结构设计和软件设计流程。通过对其在无线抄表系统中检测,接收发送数据稳定可靠。实践表明,该终端可作为一个通用模块应用到其他无线收发系统中,具有很强的实用性和可移植性的特点。     

HSPA＋网络应用

论述了智能手机对网络安全、用户感知、网络运维等方面的影响,以及全球HSPA＋网络建设状态和HSPA＋终端市场状态,同时,还介绍了HSPA＋网络设备的特点和网络解决方案的亮点。