关于E5071B，有些问题就不需要FAE了

[{"attributes":{"color":"#222222"},"insert":"E5071B网络分析仪，在天线、耦合器、滤波器等无源器件以及连接器、线缆的生产上有着广泛的应用，同时这款仪器在使用过程中也有很多问题需要注意，毕竟在测试性能和测试范围上还与E5071C有着一定差距。下面就使用中遇到的情况作简要归纳。 "},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222","bold":true},"insert":"一、 扫描频率对最大功率输出的影响"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  1. ENA系列网络分析仪默认扫描功率都是0dBm，默认功率可以满足大部分测试需求，但是对于例如放大器等某些特殊产品的测试需要增大网分输出信号的扫描功率。这时候就有可能出现功率超出限制的情况，如下图所示，终止频率设为8.5GHz，逐步调高输出频率，当超过5dBm时候左下角会出现功率超出范围提示并伴随尖锐报警声音。"},{"attributes":{"align":"justify"},"insert":"\n"},{"insert":" "},{"insert":{"image":"https://files.eteforum.com/article/202301/ce85124c5c0f29b5.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  同样设置E5071C发现功率超过7dBm会出现报警提示，经过查询比较两者指标差别如下："},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#0052ff"},"insert":"E5071B： "},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#0052ff"},"insert":"     300 kHz to 3 GHz最大输出10dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#0052ff"},"insert":"     3 GHz to 4.25 GHz 最大输出9dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#0052ff"},"insert":"     4.25 GHz to 6 GHz最大输出7dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#0052ff"},"insert":"     6 GHz to 8.5 GHz 最大输出5dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#d6a841"},"insert":"E5071C： "},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#d6a841"},"insert":"      9 kHz to 5 GHz最大输出10dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#d6a841"},"insert":"     5 GHz to 6 GHz最大输出9dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#d6a841"},"insert":"     6 GHz to 7 GHz最大输出8dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#d6a841"},"insert":"     7 GHz to 8.5 GHz最大输出7dBm"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  整体比较E5071C的功率范围要改进很多，而最新款的E5072A为了适应高功率的测试需要将最大输出功率提升至20dBm。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222","bold":true},"insert":"二、E5071B在多个channel的使用时功率"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222","bold":true},"insert":"   "},{"attributes":{"color":"#222222"},"insert":"在某家无源器件生产工厂出现如下状况，客户采用两个通道分别进行测试，CH1和CH2的触发都出于Continuous状态，但是出现报警声音并在左下角有错误提示源衰减器在频繁切换，如下图所示："},{"attributes":{"align":"justify"},"insert":"\n"},{"insert":" "},{"insert":{"image":"https://files.eteforum.com/article/202301/a80a2f109b1f4743.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  仔细调整设置后发现是由于两个channel的终止频率差距较大造成，当两个channel的截止频率都在3GHz以内时就不会出现此报警，而一个在3GHz以内，另一个在3GHz以外，就会有上述情况产生。分析原因还是由于不同的频率范围导致了不同的功率范围，使得仪器自动设置的功率范围不同而频繁切换衰减器。  解决此问题可通过把其中一个channel的功率范围手动调整和另一个相同，如下图所示，当CH1截止频率设置为8.5GHz，若Auto Range为打开状态，Power Ranges会默认为-25 to 7，CH2截止频率设置为3GHz时候如果Auto Range为打开状态，Power Ranges会默认为-30 to 2，我们关掉Auto Range，手动把CH2的Power Ranges改为-25-7，报警结束，警告消除。"},{"attributes":{"align":"justify"},"insert":"\n"},{"insert":" "},{"insert":{"image":"https://files.eteforum.com/article/202301/666b00c220741855.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#222222","bold":true},"insert":"三、时域分析的简单应用"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  在连接器和线缆的生产研发中经常会用到ENA系列网分的010选件，此选件可以把测试参数在时域上显示出来，用以实现断点定位或者在某段长度上针对性的进行测试。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"下面简单介绍一种分段测试方案，"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  1、 在1端口接入待测线缆和连接器，Meas选择S11，Format选择SWR，点击Analysis选择Transform，此时可以发现曲线的横坐标显示为长度即时域上的驻波参数，如图所示Marker1点为端口处的0距离点，Marker2为线缆的远端距离，此处需要注意这里的2.78米不是线缆的真实长度，而是真实长度的2倍乘以信号在线缆中的传输速度与光速的比值。此比值可以通过测量线缆的实际长度来计算，可用于较长的线缆中故障点定位。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":" "},{"insert":{"image":"https://files.eteforum.com/article/202301/51c010519ffb5cbf.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  2、 点击Analysis—Gating—ON，此时出现一个时间门的设置，就是把测试范围在时域上划定一个范围，此时我们如果想排除线缆的影响单独测试接头处的驻波值，可以如图设定时间门范围，调整start和stop用两面小旗放在波峰的两侧。"},{"attributes":{"align":"justify"},"insert":"\n"},{"insert":" "},{"insert":{"image":"https://files.eteforum.com/article/202301/f3b68b1c1822fa21.png"}},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  3、 点击Analysis—Transform—OFF，把测试参数恢复到频域上，连接负载，得出接头的实际驻波参数，同样道理也可以通过时间门控制在线缆所在的时域来排除接头的影响来单独测试线缆的指标，理论来讲单独测试线缆的驻波比乘以单独接头的驻波比应该基本等于整体的驻波比值。"},{"attributes":{"align":"justify"},"insert":"\n"},{"insert":{"image":"https://files.eteforum.com/article/202301/a4c5d7b0e00ee0e9.png"}},{"insert":" "},{"attributes":{"align":"center"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":"  上述仅是针对时域分析功能的最基本应用做一概括，希望能通过以上测试方式扩展大家的思路，更大程度的发挥这一功能的应用。"},{"attributes":{"align":"justify"},"insert":"\n"},{"attributes":{"color":"#222222"},"insert":" "},{"attributes":{"align":"justify"},"insert":"\n"},{"insert":"——作者 君鉴科技/板凳"},{"attributes":{"align":"right"},"insert":"\n"},{"insert":"\n"}]