Nick, thanks a lot for this detailed post. I just have a few comments to add below.

You are correct, we are using an inverted-F type antenna based on the TI DN0007 design note. The ground plane for the antenna runs the entire area of the mcmodule directly under it.

1) Surroundings: You are correct that the materials in the near field of the antenna have a large impact on the impedance which effects the matching. The antenna on the mcmodule is matched to an open air environment. Different materials have different effects on the antenna matching, plastics and wood have minimal impact whereas metals, liquids, and people (holding the device in your hand) have a huge impact on the matching. Placing the mcmodule on a drywall or wood surface will have minimal impact on the RF performance whereas placing the device on a metal door with have a LARGE impact, try placing the mcmodule as far away as possible from the metal surface for best results.

2) Ground Plane: We have done a quite a bit of RF testing of the mcmodule in an anechoic chamber enviroment. We did testing of the mcmodule both with and without the coin cell with no notable degradation of the RF performance with the coin cell installed.

3) Shielding: Placing the mcmodule in a metal fridge or freezer will have a huge impact on the rf performance. The only way for the RF signal to be received or transmitted would be through the non-metal gaskets of the freezer. Also, unless you are using a battery that is designed to work at lower temperatures the voltage of the battery will be lower with will effect the tranmitted power of the device.

4) Attenuation: Again, different materials attenuate RF signals worse than others. Metals, liquids, and people(mostly liquid) have a much greater effect then wood or plastics.

5) Orientation: Polarization of the antennas also has a large effect on the range. In our testing in an anechoic chamber environment we have seen differences of 9~10 dBm between horizontal and vertical polarization. Simply rotating your mcmodule by 90 degrees (or changing the position of the mcGateway) can have a huge impact on the range.

The 200m range we have tested is line of sight in open air.

The next iteration of the mcgateway will include a PA/LNA which will increase the power output and also the receiver sensitivity of the mcgateway. We also have a horizontally and vertically polarized antenna we can switch between to provide antenna diversity which will also increase the range. In addition to this, the mcMod120 includes a radio with slightly improved power output and receiver sensitivity as well.

If you have any other questions please post them.
 
mc-Josh