1、对于R8/R9的LTE终端，主要配置为双天线，但是采用单发双收的工作模式。上行链路MIMO的工作方式主要包括以下几种：单天线传输：采用上行单天线传输方式，使用固定天线发送（端口0）。开环发送天线选择分集：采用上行单天线传输方式，终端选择天线进行上行传输。闭环发送天线选择分集：网络侧通过下行物理控制信道上承载的下行控制信息通知终端采用特定天线进行上行传输。上行MU-MIMO：网络侧能够根据信道条件变化自适应地选择多个终端共享相同的时频资源进行上行传输下行传输LTER8/R9版本中下行引入了8种MIMO传输模式，其中LTEFDD常用的MIMO传输模式为模式1到模式6（TM1TM6），而模式7（TM
2、7）和模式8（TM8）主要应用于TDLTE系统中，下面是不同传输模式的简要说明。模式1：单天线端口传输（端口0）。模式2：开环发射分集。模式3：大延迟CDD空间复用与开环发射分集自适应。模式4：闭环空间复用与开环发射分集自适应。模式5：多用户MIMO与开环发射分集自适应。模式6：单层闭环空间复用与开环发射分集自适应。模式7：单流波束赋形（端口5）与开环发射分集或单天线端口传输（端口0）自适应。模式8：双流波束赋形（端口7和端口8）或单流波束赋形（端口7或端口8）与开环发射分集或单天线端口传输（端口0）自适应。A） SCOPE This document provides guidance fo
3、r measurement of conducted output emissions of devices or composite systems that employ a transmitter with multiple outputs in the same band or multiple transmitters operating in the same band, with the outputs occupying the same or overlapping frequency ranges. It applies to EMC compliance measurem
4、ents on devices and systems （including hosts with multiple modular transmitters） that transmit on multiple antennas simultaneously in the same or overlapping frequency ranges through a coordinated process. Examples include, but are not limited to, devices and systems employing beamforming or multipl
5、e-input and multiple-output （MIMO.） This guidance applies to both licensed and unlicensed devices wherever the FCC rules call for conducted output measurements or where conducted output measurements are combined with directional antenna gain to demonstrate compliance with a radiated limit. Guidance
6、is provided for in-band, out-of-band, and spurious emission measurements. KDB 662911工作在同一频段的多发设备处理方法，适用于如下测试项：带内发射带外发射杂散发射1. 传导输出设备独立设备多个输出多个设备多个输出2. 符合系统设备For devices having two outputs driving a cross-polarized pair of antennas, see Attachment 662911 D02 of this publication for additional guidance
7、. 对于具有水平极化天线对的双输出设备，请参阅KDB 662911 D02以获取更多指导。备注：Cross-Polarization水平极化 一般与Co-Polarization垂直极化相对.极化是指在最大辐射方向上辐射电波的极化，其定义为在最大辐射方向上电场矢量端点运动的轨迹，由于天线本身物理结构等原因，天线辐射远场的电场矢量除了有所需要方向的运动外，还在其正交方向上存在分量，这就指的天线的交叉极化。B） PURPOSE This document addresses two issues associated with conducted testing of emissions from
8、 transmitters with multiple outputs in the same band:1） Summing emissions. 发射求和The FCCs emission limits apply to the total of emissions from all outputs of the transmitter or of composite system transmitters. Thus, emission measurements from the transmitter outputs must be summed before comparing me
9、asured emissions to the emission limit. FCC的发射限值适用于发射器或复合系统发射器的所有输出的发射总量。 因此，在将测量的发射与发射限制进行比较之前，必须对来自发射机输出的发射测量求和。 Accounting for array gain. 阵列增益计算Correlation between signals transmitted from different antennas can lead to array gain, which increases the directional gain of the device and leads to
10、higher radiated levels in some directions. The contribution of array gain to the directional gain of the transmitter must be considered in rule parts where conducted in-band emission limits vary with directional gain, or in situations in which conducted measurements are combined with directional ant
11、enna gain to determine compliance with in-band radiated limits. 根据不同天线发射的信号之间的相关性可以引出阵列增益，这增加了设备的定向增益并且导致在一些方向上的较高辐射水平。在传导带内发射限制随着方向增益变化的规则部分中或者在传导测量与定向天线增益组合以确定符合带内发射限制的情况下，必须考虑阵列增益对发射机的定向增益的贡献 辐射极限。These issues are unique to conducted emissions measurements. In most cases, radiated measurements au
12、tomatically combine the power emitted from multiple outputs and include the effects of directional gain if the measurements are performed in the direction of maximum response of the transmitter.传导发射测量：需要计算定向增益辐射测量：不需要计算，因为辐射测试会自动组合从多个输出发射的功率，并且包括方向增益的影响 C） LIMITATIONS This document provides guidance
13、 only with respect to summing of emission measurements from multiple outputs and performing directional gain computations. It makes no change in other aspects of measurements and compliance, such as the type of power or power spectral density measurement to be made （e.g., peak or average） or the met
14、hods for making those measurements （e.g., spectrum analyzer setup parameters）. 这个文档只对多天线设备发射测量和定向增益计算，不涉及其他测试方法和设置方面D） DEFINITION Measure-and-sum technique. The conducted emission level （e.g., transmit power or power in specified bandwidth） is measured at each antenna port. The measured results at t
15、he various antenna ports are then summed mathematically to determine the total emission level from the device. Summing is performed in units that are directly proportional to power （e.g., mW or microvolts-squarednot dBm or microvolts）. 测量与求和技术。在每个天线端口处测量传导发射功率（例如，指定带宽中的发射功率或功率）。 然后在各个天线端口处的测量结果在数学上求
16、和以确定来自设备的总发射功率。 以与功率成正比的单位（例如，mW或微伏平方 - 不是dBm或微伏）执行求和。E） GUIDANCE FOR SUMMING EMISSION MEASUREMENTS FROM MULTIPLE OUTPUTS OF A TRANSMITTER OR FROM MULTIPLE TRANSMITTERS 发射器或多个发射器的多个输出的发射测量的指导Acceptable methodologies for summing emission measurements from multiple transmitter outputs depend on the ty
17、pe of emission measurement being performed. Three types of emission measurements are considered: in-band power measurements; in-band power spectral density measurements; and out-of-band and spurious emissions measurements. 考虑三种类型的发射测量：带内功率测量;带内功率谱密度测量;带外和杂散发射测量。1） In-Band Power Measurements The meas
18、ure-and-sum technique shall be used for measuring in-band transmit power of a device. Total power is the sum of the conducted power levels measured at the various output ports 总功率是在各个输出端口处测量的传导功率的总和2） In-Band Power Spectral Density （PSD） Measurements When performing measurements for compliance with
19、PSD limits within the band of operation of a transmitter, any of the three techniques below may be used to combine the emission measurements from multiple outputs prior to comparing to the emission limit. The first is the most accurate method. The second and third techniques are offered as simpler a
20、lternatives, but they may lead to overestimates of the total PSD when emission levels differ between outputs; consequently, if measurements performed using methods b） or c） exceed the emission limit, the test lab may wish to retest using method a） before declaring that the device fails the emission
21、test. With any of the methods, existing rules and guidance shall be applied in performing the measurements on the individual outputs and in determining the maximum permitted PSD for the device. 当在发射器的操作频带内执行符合PSD限制的测量时，下面的三种技术中的任一种可以用于在与发射限度比较之前组合来自多个输出的发射测量。第一种是最准确的方法。第二和第三技术被提供为更简单的替代但是当输出之间的发射水平不
22、同时，它们可能导致总PSD的过高估计; 因此，如果使用方法b）或c）进行的测量超过发射限值，则测试实验室可能希望在声明设备未通过发射测试之前使用方法a）重新测试。 使用任何方法，在执行各个输出的测量和确定设备的最大允许PSD时，应应用现有规则和指导。a） Measure and sum the spectra across the outputs. With this technique, spectra are measured at each output of the device at the required resolution bandwidth. The individual
23、spectra are then summed mathematically in linear power units. Unlike in-band power measurements, in which the sum involves a single measured value （output power） from each output, measurements for compliance with PSD limits involve summing entire spectra across corresponding frequency bins on the va
24、rious outputs i.e., for a device with NANT transmitter outputs, if the spectrum measurements of the individual outputs are all performed with the same span and number of points, the spectrum value （in watts or milliwatts） in the first spectral bin of output 1 is summed with that in the first spectra
25、l bin of output 2 and that from the first spectral bin of output 3, and so on up to the NANTth output to obtain the value for the first frequency bin of the summed spectrum. The summed spectrum value for each of the other frequency bins is computed in the same way）. 举个例子：对于具有N个发射机输出的设备，如果各个输出的频谱测量都使
26、用相同的Span和扫描点数：测量出第1端口的第一段频谱图（以瓦特或毫瓦为单位）测量出第2端口的第一段频谱图测量出第3端口的第一段频谱图直到测量出第N端口的第一段频谱图, 以相同的方式计算每个端口第一段频谱图相加b） Measure and sum spectral maxima across the outputs. With this technique, spectra are measured at each output of the device at the required resolution bandwidth. The maximum value （peak） of eac
27、h spectrum is determined. These maximum values are then summed mathematically in linear power units across the outputs. These operations shall be performed separately over frequency spans that have different out-of-band or spurious emission limits计算最大值：在标准要求的RBW内，线性计算所有的输出端口的最大值的总和c） Measure and add
28、 10 log（NANT） dB, where NANT is the number of outputs. With this technique, spectrum measurements are performed at each output of the device, but rather than summing the spectra or the spectral peaks across the outputs, the quantity 10 log（NANT） dB is added to each spectrum value before comparing to
29、 the emission limit. The addition of 10 log（NANT） dB serves to apportion the emission limit among the NANT outputs so that each output is permitted to contribute no more than 1/NANTth of the PSD limit specified in the rules. （Note that the 10 log（NANT） term in this calculation is not related to that
30、 used in array gain calculations, to be discussed later in this document.） 在与发射限值比较之前，将10 log（N）dB的量加到每个端口的测试值上。将10log（N）dB分配到N跟发射输出天线上，每个输出允许的值不超过标准规定的PSD限值的1 / N。 （请注意，此计算中的10 log（N）项与阵列增益计算中使用的术语无关，本文档后面将对此进行讨论。）3） Out-of-Band and Spurious Emission Measurements a） Absolute Emission Limits （绝对限值）W
31、hen performing measurements outside of the band of operation of a transmitter （i.e., out-of-band and spurious emissions）, any of the three techniques below may be used to combine the emission measurements from multiple outputs prior to comparing to the emission limit. The first is the most accurate method. The second and third techniques are offered as simpler
