使用CC2591作为CC2530的功放
使用CC2591作为CC2530的功放, CC2591 PAThe absolute maximum ratings and operating conditions listed in the CC2530 datasheet [1]and the CC2591 datasheet [4] must be followed at all times. Stress exceeding one or more ofthese limiting values may cause permanent damage to any of the devicesNote that these characteristics are only valid when using the recommended register settingspresented in Section 4.6 and in Chapter 8, and the CC2530 - EM reference designOperating Frequency240524835MHzOperating Supply Voltage2036VOperating Temperature-40CTC=25C, VDD=3.0V, f=2440 MHz if nothing else is stated. All parameters are measuredon the CC2530-Cc2591EM reference design [11] with a 50 Q2 loadReceive CurrentWait for sync, -90 dBm input levelWait for sync, -50 dBm input level24mATXPOWER OXE5166mATXPOWER OXD5149mATXPOWER OXC5138mATXPOWER OXB5127mATransmit currentTXPOWER OXA5115ATXPOWER = 0X95100mATXPOWER = 0X8594ATXPOWE=0×75mATXPOWE=0×6579APower Down Current PM2UAISTRUMENTSPage 3 of 19SWRA308ATC=25C, Vdd=3.0V, f= 2440 MHz if nothing else is stated. All parameters are measuredon the CC2530-CC2591 EM reference design with a 50 Q2 loadReceive Sensitivity HGM 1 %PER, IEEE 802. 15.4[6] requires -85 dBm-988dBmReceive Sensitivity LGM1 PER, IEEE 802. 15.4 [6] requires -85 dBm-90.4dBmSaturationlEEE 802.15. 4 [6] requires-20 dBm10dBmWanted signal 3 db above the sensitivity levelIEEE 802.15.4 modulated interferer at ieee 802.15.4 channelsInterferer Rejection+5 MHz from wanted signal, IEEE 802. 15. 4 [6] requires 0 dBdB+10 MHz from wanted signal, IEEE 802. 15. 4 [6] requires 30 dB49dB+20 MHz from wanted signal wanted signal at- 82d BmdBdue to in the external lna and the offset in cc2530 the rssi readouts from cc2530CC2591 is different from rssi offset values for a standalone cc2530 design the offsetvalues are shown in table 4.4High Gain Mode79LoW Gain mode67Real rssi Register value-Rssl offsetISTRUMENTSPage 4 of 19SWRA308ATc=25C, Vdd=3.0V, f=2440 MHz if nothing else is stated All parameters are measuredon the CC2530-CC2591 EM reference design with a 50 Q2 load Radiated measurements aredone with the kit antennaRadiated Emissionwith TXPOWer Oxe5Conducted 2. RF (FCC restricted band)-462|dBmConducted 3. RF(FCC restricted band46.5 dBmComplies withFCC 15.247. SeeChapter 7 for moredetails about regulatoryRadiated 2.RF(FCC restricted band)42.2dBmrequirements andcomplianceIEEE 802.15.4[6]requires max.35%%Measured as defined by IEEE 802.15. 4 6TXPOWER OxE5. f= EEE 802.15. 4 channels13TXPOWER= OXD5. f= EEE 802.15.4 channelsTXPOWER= OXC5 f= EEE 802.15.4 channelsMax error∨ ectorTXPOWER OxB5 f= IEEE 802.15. 4 channelsMagnitude(EVM)TXPOWER OxA5. f= IEEE 802.15.4 channelsTXPOWER 0X95. f= IEEE 802. 15.4 channels643333%%%%%%%TXPOWER= 0x85. f= iEEE 802. 15.4 channelsTXPOWER =0x75 f= IEEE 802. 15.4 channels%TXPOWER= 065. f= iEEE 802. 15.4 channelsThe RF output power of the CC2530- CC2591 EM is controlled by the 7-bit value in theCC2530 TXPOWER register. Table 4.6 shows the typical output power and currentconsumption for the recommended power settings The results are given for Tc= 25 C, Vdd3.0V and f= 2440 MHz, and are measured on the cC2530-CC2591 EM reference designwith a 50 Q2 load. For recommendations for the remaining CC2530 registers, see Chapter 8 oruse the settings given by SmartRF StudioOXE520166OxD519149OxC18138OxB517127OxA5161150x95141000x8513940X75860x651079Note that the recommended power settings given in Table 4.6 are a subset of all the possibleTXPOWER register settings. However, using other settings than those recommended mightINSTRUMENTSPage 5 of 19SWRA308Aresult in suboptimal performance in areas like current consumption, EVM, and spuriousemissionTc=25C, Vdd=3.0V, f=2440 MHz if nothing else is stated All parameters are measuredon the CC2530-CC2591EM reference design with a 50 32 load2221-2V201918171611121314151617181920212223242526251510OxE5OxC5OxA50X850x65540-30-20-1001020304050607080ISTRUMENTSPage 6 of 19SWRA308A98Avg 3.6VAva 3vAvg 2V110111213141516171819202122232425261023.6V-1062V-110-40-30-20-100102030405060708070604020-Wanted signal at:-82 dBm10ISTRUMENTSPage 7 of 19SWRA308ACC2530-CC2591EM High Gain ModeC C2530-CC2591EM Low Gain Mode- CC2530EM40000-100110100908070-60-50-40-30-20-100The IEEE standard 802.15. 4 [8] requires the transmitted spectral power to be less than thelimits specified in table 4.7If-fc>3.5 MHz-20 dB-30 dBmThe results below are given for Tc=25 C, Vdd=3.0V and f= 2440 MHz, and are measuredon the CC2530-CC259 1EM reference design with a 50 Q loadIEEE absoluteChannel 182432.52435243752442524452447.5ISTRUMENTSPage 8 of 19SWRA308AOnly a few external components are required for the CC2530-CC2591 reference design. Atypical application circuit is shown below in Figure 5.1. Note that the application circuit figuredoes not show how the board layout should be done. The board layout will greatly influencethe RF performance of the CC2530-CC2591EM. TI provides a compact CC2530CC2591 EM reference design that it is highly recommended to follow. The layout, stack-upand schematic for the CC2591 need to be copied exactly to obtain good performance. Notethat the reference design also includes bill of materials with manufacturers and part numbersL102 L10=TI INF inductorVDD13cc2530LA 1RF PANTCC2591 RF NFNPA EN(P1 1)i工工I NA FNP:1HGM ENPO 7)T:1Proper power supply decoupling must be used for optimum performance. In Figure 5.1, onlythe decoupling components for the CC2591 are shown. This is because, in addition todecoupling, the parallel capacitors C11, C101, and C131 together with, L101, L102, TL11TL101 and TL131 also work as RF loads. These therefore ensure the optimal performancefrom the CC2591. C161 decouples the AvDD blAs power.The placement and size of the decoupling components, the power supply filtering and thePCB transmission lines are very important to achieve the best performance Details about theimportance of copying the CC2530-CC2591EM reference design exactly and potentialconsequences of changes are explained in chapter 6The RF input/output of CC2530 is high impedance and differential. The CC2591 includes abalun and a matching network in addition to the PA, LNa and RF switches which makes theinterface to the CC2530 seamless. Only a few components between the CC2530 andCC2591 necessary for RF matching For situation with extreme mismatch(VSWR 6: 1 till 12: 1out-of-band as shown in Figure 6.2) it is recommended to include all the components asshown in Figure 5.1ISTRUMENTSPage 9 of 19SWRA308ANote that the PCB transmission lines that connect the two devices also are part of the RFmatching. It is therefore important to copy the distance between the devices, the transmissionlines and the stack-up of the PCB according to the reference design to ensure optimumperformanceThe network between the CC2591 and the antenna(L111, C112, C111 C113 and L112matches the CC2591 to a 50 2 load and provides filtering to pass regulatory demands. C111also works as a dc-blockR151 is a bias resistor the bias resistor is used to set an accurate bias current for internaluse in the cc2591The TI reference design contains two antenna options. As default, the Sma connector isconnected to the output of CC2591 through a 0 Q2 resistor. This resistor can be soldered offand rotated 90 clockwise in order to connect to the PCB antenna, which is a planar invertedF antenna(PIFA). Note that all testing and characterization has been done using the SMAconnector. The PCB antenna has only been functionally tested by establishing a link betweentwo EMs. Please refer to the antenna selection guide [6] and the Inverted F antenna designnote [7 for further details on the antenna solutionsISTRUMENTSPage 10 of 19SWRA308A
- 2020-11-30下载
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支持向量机
关于支持向量机里面讲核函数的,介绍了线性核函数、高斯核函数、及多项式核函数等。还介绍了核函数的判定以及Mercer定理1x1121T3212T42.3p(a)L313x2.3.32cT1V2C.223+d更一般地,核数K(x2z)=(xz+)“对应的映射后特征维度为a(求解方法参见http://zhidao.baiducom/question/16706714.html)由于计算的是内积,我们可以想到IR中的余弦相似度,如果ⅹ和z向量夹角越小,那么核函数值越大,反之,越小。因此,核函数值是(x)和(z)的相似度。再看另外一个核函数K(r, z)=expz-z|222这时,如果x和z很相近(x-2‖≈0),那么核函数值为1,如果x和z相差很大(x-2》0),那么核函数值约等于0。由于这个函数类似于高斯分布,因此称为高斯核函数,也叫做径向基函数( Radial basis function简称RBF)。它能够把原始特征映射到无穷维。既然高斯核函数能够比较ⅹ和z的相似度,并映射到0到1,回想 logistic回归, sigmoid函数可以,因此还有sigmoid核函数等等下面有张图说明在低维线性不可分时,映射到高维后就可分了,使用高斯核函数。Linear回回看目即Gaussian来自 Eric Xing的sdes注意,使用核函数后,怎么分类新来的样本呢?线性的时候我们使用SVM学与出W和b,新来样木ⅹ的话,我们使用wTx+ b来判断,如果值大于等于1,那么是正类,小于等于是负类。在两者之间,认为无法确定。如果使用了核函数后,W2x+b就变成了wφ(x)+b,是否先要找到p(x),然后再预测?答案背定不是了,找φ(x很麻烦,回想我们之前说过的wa+6=boy(0)x+bi=1(x(,x)+b只需将替换成(x,x),然后值的判断同上8核函数有效性判定问题:给定一个函数K,我们能否使用K来替代计算φ(x)2中(z),也就说,是否能够找出一个,使得对丁所有的x和z,都有k(x,2)=(x)r中(2)9比如给出了K(x,2)=(x2)2,是否能够认为K是一个有效的核函数下面来解决这个问题,给定m个训练样本全(r(3xm,每一个对应一个特征向量。那么,我们可以将(e) yJ仟意两个和带入K中,计算得到=0。I可以从1到m,j以从1到m,这样可以计算出m*m的核函数矩阵( Kernel Matrix)。为了方便,我们将核函数矩阵和(x,z)都使用K来表示如果假设K是有效地核函数,那么根据核函数定义k1=K(x0x0)=p(x()p(x0)=p(x(0)p(x()=K(x(,x)=K可见,矩阵K应该是个对称阵。让我们得出一个更强的结论,首先使用符号中x(x)来表示映射函数中(x)的第k维属性值。那么对于任意向量z,得2K2=∑∑2K3∑∑(m0y(0)2∑∑∑(z0)(x0)z∑∑∑29(x)k(z0)k i j=S|∑zipk(c(ak0.最后一步和前面计算K(x)=(x2)时类似。从这个公式我们可以看出,如果K是个有效的核函数(即K(xz)和(x)p(2)等价),那么,在训练集上得到的核函数矩阵K应该是半正定的(K≥0这样我们得到一个核函数的必要条件:K是有效的核函数==>核函数矩阵K是对称半正定的可幸的是,这个条件也是充分的,由 Mercer定理来表达。Mercer定理:如果函数K是×四→巫上的映射(也就是从两个n维向量映射到实数域)。那么如果K是一个有效核函数(也称为 Mercer核函数),那么当且仅当对于训练样例(r()x(m,其相应的核函数矩阵是对称半正定的。Mercer定理表明为了证明K是有效的核函数,那么我们不用去寻找φ,而只需要在训练集上求出各,然后判断矩阵K是否是半正定(使用左上角主子式大于等于零等方法)即可。许多其他的教科书在 Mercer定理证明过程中使用了范数和再生希尔伯特空间等概念,但在特征是n维的情况下,这里给出的证明是等价的。核函数不仅仅用在SWM上,但凡在一个模型后算法中出现了,我们都可以常使用区(xz)去替换,这可能能够很好地改善我们的算法。posted on2011-03-1820:22 Jerry Lead阅读(…)评论(…)编辑收藏刷新评论刷新页面返回顶部博客园首页博问新闻闪存程序员招聘知识库Powered by:博客园 Copyright@ Jerry Lead
- 2020-12-01下载
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