如何降低蓝牙系统的成本

蓝牙工业界有一个雄心勃勃的计划，要将整个蓝牙接收器/发射器的价格控制在仅仅5美元，其中包括了基于DSP的子系统及相应的ROM和RAM。而这要等到蓝牙无线技术有了相当大的市场规模，并且通过大规模的投产来产生经济效益之后，才有可能成为现实。在这场角逐中，某些制造商可能会抢占先机。例如，到2001年6月，CSR公司已经生产了超过1百万块BlueCore单片蓝牙产品，目前市场上带蓝牙功能的所有终端用户产品中，48%都采用了这款芯片。本文介绍了CSR所采用的一些产品设计方法，以尽可能降低蓝牙产品的成本，同时还介绍了可能影响蓝牙产品…     

EFFICIENT SIXTH ORDER P-STABLE METHODS WITH MINIMAL LOCAL TRUNCATION ERROR FOR y"=f(x,y)

1. IntroductionWe consider a class of direct hybrid methods proposed in [11 for solving the second orderinitial value problemy" = f(t,y), y(0),y'(0) given (1.1)The basic method has the formandHere t. = nh and we define t.l.. = t. I aih, i = 1, 2 and n=0,1…     

雷达天线罩上积雪引起的信号电平降低

本文作者已测量过由天线罩上的积雪所引起的接收信号电平和天线方向图的变化,观察到天线罩上雪不对称地堆积时出现的大的信号电平衰减现象。     

用于军事和工业系统的声表面波器件

自从制成了叉指换能器以来,声表面波器件获得了很大的进展.目前,这种器件已经广泛地用于完成复杂系统的信号处理功能方面.     

Electronic Properties of Red P-Type Tl2S5 Single Crystals

Single crystals of red Tl2S5 were prepared by a special modified vertical Bridgman and Stockbarger technique.This growth was performed in our laboratory. The influences of temperature on the electrical conductivity, Hall mobility, carrier concentration, and thermoelectric power (TEP) were carried out in the temperature range 277-413K. Throughout these measurements, various physical parameters such as effective mass of charge carriers,carrier mobility, diffusion coefficient, and the relaxation time for both majority and minority carriers were found.     

Pre—Separation Axioms in Fuzzifying Topology

1　 IntroductionYing[5,6 ] introduced and elementally developed so called fuzzifying topology with the semanticmethod of continuous valued L ogic.Shen[7] introduced and studied T0 -,T1-,T2 (Hausdorff) -,T3(regularity) -,T4 (normality) -separation axioms in fuzzifying topology.In [3 ]the concepts of thefamily of fuzzifying pre-open sets,fuzzifying pre-neighbourhood structure of a point and fuzzifyingpre-closure are introduced and studied.It is worth to mention that pre-separation axioms are …     

Numerical Calculation and Analysis of Track Etching Process

Heavy ion irradiated polymers can be chemically etched to form track membrane with pores in the micro and sub-micro ranges. It has been reported that pore growth during etching can be related to track structures. A latent track has a track core inside and a track halo surrounding the track core. By single track etching it is observed that etching in the track core is much faster than in the track halo where the etching rate is even lower tlian that of bulk material. For multi-track etching, no such stages can be seen by the conductance measurements.     

CO、H_2及HO_2在Co/SiO_2催化剂上吸附的原位红外光谱

用原位IR研究了CO在Co/SiO_2催化剂上的吸附,并考察了吸附的CO与H_2、H_2O的相互作用。CO在Co/SiO_2上的吸附显示出四种不同的吸收峰。2002、2027cm~(-1)归属于端基CO吸附;2120cm~(-1)归属于CO在钴离于上的吸附;1870cm~(-1)为CO的桥式吸附;1720cm~(-1)则为多中心吸附。当温度高于370K时,吸附的CO会完全脱附。H_2与吸附的CO相互作用可削弱CO吸收峰的强度,并逐步在低波数(1980cm~(-1))处产生一个小肩。水与吸附的CO相互作用产生一种甲酸基物种(1585、1390cm~(-1))。该物种被认为是Kòlbel-Engelhardt反应的中间体。     

15C的中子晕结构研究

实验测量了83A MeV ^14,15C的核反应总截面(σ_R)及¹⁵C产生^14,15C和¹⁴C产生¹³C的动量分布(P_//). 分析得到了¹⁵C产生¹⁴C和¹³C的动量分布半高宽(FWHM)分别为71±9MeV/c和223±28MeV/c, 而¹⁴C产生¹³C的FWHM为195±21MeV/c. 从¹⁵C和¹⁴C产生¹³C的FWHM与Goldhaber模型的预言基本一致. 而¹⁵C产生¹⁴C的FWHM却要比该模型计算小得多. 同时观测到¹⁵C的σ_R比相邻核有反常增加. 在Glauber模型框架中, 对实验测得的P_//和σ_R进行了探讨. P_//和σ_R的分析结果同时显示¹⁵C的最后一个中主要处于s_1/2态, 具有中子晕结构.