This year I followed an Ekahau Certified Survey Engineer (ECSE) training presented by Ferney Muñoz. I can only say that this training is a must for people who want to do a site survey with Ekahau Site Survey (ESS). One of the topics discussed there was the measurement of attenuation of obstacles (walls, areas, etc.). Although this is well explained during the training, both Devin Akin (http://divdyn.com/measuring-annotating-wall-attenuation/) and Nigel Bowden (https://www.ekahau.com/blog/2015/09/07 / wi-fi-planning-walls-and-dbs-measuring-obstruction-losses-for-wlan-predictive-modeling /) have written very good blogs which you should read if you want to carry out a predictive site surveys with ESS.
Both in the course and in the aforementioned blogs there is a Buffalo AirStation AC433 Wireless Travel Router mentioned as the WLAN RF source. Of course you can also choose the access point that is actually used or will be used, but I am particularly looking for a compact and therefore easily portable solution. The disadvantage of the Buffalo AirStation AC433 is that it is not sold and is not suitable for Europe. When searching for an alternative, I came across a TP-Link AC750 Wi-Fi Travel Router (https://www.tp-link.com/en/products/details/cat-9_TL-WR902AC.html). This router is generally available for about 40 euros.
However, this is only the first part of an easily movable solution; I also need a stand to place the AP on and a battery that can supply the AP with electricity for a day. Luckily I was already in possession of a number of powerbanks which I had received as a promotional gift and they were good for this putpose. I was most impressed by Xtorm Power Bank of 6000mAh but also a brandless power bank of 4000mAh was fine.
For the standard I have opted for a cheap tripod (11 euros), please note that this is at least 100 cm high.
From this I had the head removed and a hollow table leg with a shelf mounted on it. And ready: a compact portable solution for doing RF attenuation measurements.
This is a first version and probably there is still some things to improve such as Velcro fastening to facilitate moving and perhaps a second tripod for doing the measurement also I consider to somehow use the original head of the tripod.
To do the measurements as said, I follow the advice on both course and blogs. It should be noted that the measurements made with an Aircheck G2 and a MacBook Pro with WiFi Explorer Pro gave me better, more reliable, more stable results than the measurements with a mobile phone.
Finally, I would like to see that, since you already have the best measuring equipment with ESS and Sidekick, there is a facility within ESS that makes it possible to do this kind of measurements. For example: draw a line or area with AP on one side of the line / surface and measure on the other side of line or area after you have first done an FSPL measurement or measure on both sides of line / area. You can also immediately indicate on the map where you took the measurements.