Mobile broadband can be quite challenging from an interference perspective with certain band configurations posing significant risks. For example when 700/800 MHz is implemented in the same locale there is a huge potential for intermodulation products polluting the receiver uplink band as the downlink bands of 700/800 MHz are neighbours and many channel arrangements can lead to problematic third order products. The risk of issues can be especially difficult when working with within metallic structures because external interference can be generated due to the semiconducting properties of rust when illuminated by antenna systems. This is particularly acute on a boat or offshore structure as rusty is often not hard to find!
In illustrating the issue to help explain to others, I updated the IMP calculator and have improved the legend, added labelling as well as numerous other small enhancements.
An example of the new graphical display is a typical scenario with the highest of the three 10 MHz blocks in 800 intermodulating with the middle 700 block causing third order products in every 700 uplink block.
Other configurations are worse with products falling in both uplink bands as shown below.
You can find the software on the downloads page and it is yours to enjoy as-is. The software still doesn’t have an installer so you will need to ensure the runtime dependencies are present such as provided by Visual Basic 6.0 Runtime Plus.