External antenna connector
The presence
of a connector for an external removable antenna in the modem design. The meaning of all external antennas is described above; here we note that the connector makes it possible to use rather large antennas with the modem, which significantly exceed the capabilities of stock antennas (both internal and external non-removable ones). In addition, the user can choose the antenna at his discretion.
SIM card slot
The presence
of a slot for a SIM card in the design of the modem. The abbreviation SIM stands for Subscriber Identification Module, and this is the main purpose of these cards — binding the device to a specific subscriber account (personal account, mobile number, etc.). Note that in this case, the term SIM refers to both the original cards of this standard used in GSM networks, and USIM used in 3G W-CDMA networks (with all relevant add-ons, see "Transmission Technologies"). The presence of a SIM slot is mandatory for modems that support the mentioned communication technologies — they practically do not use firmware for binding to the operator's network.
GPS
The presence
of a GPS module in the design of the modem. This module allows you to track the current geographic coordinates of the device; but the options for working with coordinate data can be different. The most popular way to use such models is to use them as an external GPS module for a laptop or other device.
Operating time (internet browsing)
The maximum operating time of the modem with battery power (see "Power") on a single charge in Internet browsing mode. Such power is typical for Wi-Fi routers, therefore, usually, Internet browsing is supposed to provide access to the World Wide Web for an external Wi-Fi device.
This spec is the main indicator of battery life for any battery-powered modem, because it describes the time of using it for its main purpose without recharging. At the same time, you should know that this indicator is measured under certain "perfect" conditions; the actual operating time depends on a number of factors, including the intensity of browsing, the amount of data transferred, the number of connected devices and the distance to them, the cellular network signal strength, etc. Therefore, in fact, the battery life of the modem may be somewhat lower. Nevertheless, it is quite possible to compare different models with each other according to the operating time stated in the specs.
