如何找到E7495B的灵敏度？

您好，我正在尝试找到E7495b无线基站测试仪预期灵敏度的规范。
具体而言，有许多软件功能允许无线（OTA）接收商用蜂窝信号，以验证网络性能。
选项可用于GSM，CDMA2K和W-CDMA。
但是，讨论这些软件选项操作的参考手册提到用户应该A）插入感兴趣的基站的测试端口，或者B）将测试盒放在附近的视线内到基站的
利益。
我很欣赏这样一个事实：执行OTA测试并不是一件容易的事情（视线很可能只是一种确保接收器同步和提供有效测量的足够强的SNR的方法），但我想知道是否
如果没有基站的视线，E7495b中存在一些基本的硬件限制，这将限制OTA测量的软件选项成功。
通过内置前置放大器，我假设噪声系数相当低（可能没有商用手机那么低，但可能小于10 dB），即使没有视线也能提供良好的性能。
该手册讨论了无法保证性能的“边际”SNR，但据我所知，测量范围应该比手册中提到的视线要求好一些。
任何有关接收器灵敏度/性能应该在此预期的轶事（或其他）指导将不胜感激。
非常感谢，约翰



     以下为原文

  Hello,
I'm trying to locate a spec for the expected sensitivity of the E7495b Wireless Basestation Tester.  Specifically, there are a number of software features that allow over-the-air (OTA) reception of commercial cellular signals for the purpose of validation of the network's performance.  Options are available for GSM, CDMA2K, and W-CDMA.  However, the reference manual discussing the operation of these software options mentions that the user should either A) plug in to the test port of the basestation of interest, or B) locate the test box within nearby line-of-sight to the basestation of interest.

I appreciate the fact that it isn't an easy task to perform OTA testing (and line-of-sight is likely just a way to ensure sufficiently strong SNR for the receiver to synchronize and provide valid measurements), but I'm wondering if there is some fundamental hardware limitation in the E7495b that would prevent the software options for OTA measurements from being made successfully if line of sight to the basestation isn't available.  With the built-in preamp, I'm assuming that the noise figure is reasonably low (maybe not as low as a commercial cell phone, but presumably less than 10 dB), which would provide good performance even without line-of-sight.  The manual talks about a "marginal" SNR where performance isn't guaranteed, but from what I can tell, the range of measurement should likely be a good bit better than the line-of-sight requirement called out in the manual.

Any anecdotal (or other) guidance of what sort of receiver sensitivity/performance should be expected here would be appreciated.

Thanks much,
John