How to choose a router and a communication operator with a modem?

Question

Iron

There is a room with very poor communication reception, that is, if you move away from the window, you get the feeling that you live in a bunker underground, paid external Wi-Fi does not break through. There was an idea to make my point.
It is realistic to make only the Internet through a "sim" modem, since they will not be allowed to lay a cable. It follows from this that the modem must be at least close to the window in order to catch a connection, that is, you need a bunch of router + modem.
Never dealt with such pieces of iron before. I ask for advice in choosing. The budget is not very big. The telecom operator is most interested in whether anyone provides absolute unlimited with adequate prices?

Answer 1

As always, we read the comments - Unlimited Yota, but is there an alternative?
Of course, the USB modem needs to be taken out into the street, onto a bar with an irradiator.
Or buy a 3G modem with the ability to connect an external antenna. Already selling kits.
Mikrotik hAP - 2.4GHz AP, Five Ethernet ports, POE-out on port 5, USB for 3G/4G support
Mikrotik mAP 2n -2.4GHz micro AP, 400MHz CPU, 64MB RAM, 2xEthernet, PoE out
Mikrotik RB951G-2HnD - 2.4Ghz 1000mW AP, 5xGigabit Ethernet, USB, 600MHz CPU, 128MB RAM

Answer 2

создается ощущение что живешь в бункере

Излучение на LTE`шных частотах плохо проникают сквозь стены. Так что, в некотором роде, так и есть.
По поводу "провестик абель не разрешают" - никак.
Можно поставить роутер с USB-модемом - но придется либо модем на удлинитель вешать и за окно выносить, либо к модему антенну (и прокладывать кабель), либо купить (не знаю как называется класс устройств) модем со встроенной раздачей вайфая, но придется подводить питание для зарядки (он от аккумулятора работает)