I have a 4GEE Wifi mini it came as a package with EE, two phones, two watches, and router they all it seems share the data allocation, not my idea wife got them, in the main it is used in the car to power the tablet that does the sat nav, but has also been used in the caravan. I see no option for an external aerial. You can get signal boosters however never tried one, the mini router on a non slip pad on car dash works well with tow car, I think the Jag has a booster built in?
Most camp sites seem to offer wifi, so not often required on site, and those without wifi seem to be in very poor reception areas and nothing will work.
Oh and Ariel is a moon of Uranus, and a motor bike and many other things, like a British satellite research programme, aerial also has many meanings as well as a device for receiving radio signals, and anyone using audio to text is likely to find it is spelt wrong, my hand has recovered a bit now so I can use a key board, but for a long time I had to use speech to text programs, and I feel it is wrong to point out peoples disabilities, in fact I think it breaks the law? Be it because of using speech to text software or simply dyslexic, many people will miss spell words, and unless there is some reason where meaning needs clarifying like low voltage or extra low voltage, then it is rude at least to correct people, and I am sure against forum rules, plus linking it to a commercial product is advertising.
I can see the idea of correcting as part of a answer, but when no advice has been offered, and the post is simply a rude comment then I would hope the moderators would remove the post and if it continued ban the person.
Returning to phone reception I have had some odd problems, I went to a summit, with whole idea of working out range of a radio, and wanted to call a friend to get him to turn on his radio, but mobile phone would not work, but with my radio I was talking to people 40 miles away, I will guess the phone was opening too many cell sites? But it seems too good of a reception can also be a problem, and in a place called Tywyn on the beach I lost signal when some one started using their phone, walking past them and redialling I got through and it seemed they lost signal. I don't know exactly why, but from that it could mean some one else using the phone can stop the signal. It does not work simply like radio reception.