Connected devices, up to
The largest number of devices that can be simultaneously connected to the modem via Wi-Fi (see "Connection").
The presence of this limitation is due to the fact that processing network requests from several devices at once requires a fairly large amount of computing resources, and there are not so many of them in miniature electronics like wireless modems. However, even inexpensive models can support about 5 – 6 devices, which is more than enough for most cases; and in more advanced modems, this number can reach 10.
Ports
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USB plug. The presence in the design of the modem of its own USB plug, which allows you to connect the device to a computer directly. Such a connection provides a device with a USB port with Internet access, and the power necessary for the operation of the modem is also supplied via USB.
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microUSB. A smaller version of the USB connector (see above), used primarily in Wi-Fi modems (see "Type") that can work autonomously and do not require a constant connection to another device. At the same time, in 3G/
4G modems, microUSB usually looks like a socket, not a plug, and a special cable is used to connect. This interface usually plays the role of a general-purpose service connector: the battery is charged through it, and it is also connected to a PC or other device to manage settings, update firmware, etc.
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USB. Wired interface, the most common and universal modern standard used to connect peripheral equipment to various electronic devices, ranging from computers to smartphones and even wireless modems. In this case, the full-size version of the USB connector is meant. It is usually installed in classic modems (see "Type") and has the form of a plug, with which the modem is connected to a control device (PC, laptop, tablet, etc.). Power is usually supplied through the same connector.
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...>USB-C. Connector, in its functional features similar to the paragraph above. With the exception of the symmetrical form factor and the use of more modern technologies.
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LAN (RJ45). Classic wired connection via a cable with an RJ-45 connector. Also known as "LAN". Nowadays, it is one of the most common methods of wired Internet connection, and is also widely used in local networks. With it, you can connect a laptop or PC directly to the modem via a cable and not bother with a Wi-Fi connection. In addition, such a connection can be faster (depending on the speed of the LAN).
— ExpressCard. A connection interface mainly used in laptops. Peripheral devices of this standard, including wireless modems, have the form of cards, when connected, they are installed in a special slot in the device. It should be taken into account that there are two ExpressCard form factors — 54 mm and 34 mm, and 34 mm cards can be used without restrictions with 54 mm slots, but not vice versa. Therefore, when choosing such a modem, it is worth clarifying the correspondence of its form factor to the planned slot. However, this standard is gradually disappearing from the scene, being replaced by more advanced interfaces — in particular, USB 3.0.
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.
MIMO antenna connection
The ability to connect the MIMO antenna (the antenna itself, usually, must be purchased separately).
MIMO technology is used in Wi-Fi communications, as well as in 4G LTE networks (starting with Cat.2). Its general principle is to split the transmitted signal into several transmitting and receiving antennas; at the same time, each of the transmitting antennas broadcasts a signal to all receiving antennas at once (or at least to several of them). This format of operation allows more efficient use of the frequency range, increases the actual data transfer rate, and also increases resistance to interference. But antennas for MIMO are rather bulky, in the case of modems it is difficult to make them built-in; and such feature is required not so often. Therefore, separate external antennas are used to work with this technology.
Note that even in portable Wi-Fi hotspots (see "Type"), this feature is used exclusively for 4G/LTE; Wi-Fi connection is provided by built-in antennas.
Memory card slot
The presence
of a slot for memory card in the design of the modem. Memory cards are very popular in modern electronics as removable storage media; in wireless modems, there are two main options for working with them. The first one provides use as an external card reader, for exchanging information between the card and the device to which the modem is connected via USB (see below); Simply put, installing a card turns the modem into a "flash drive" with removable storage. And in models with Wi-Fi (see "Type"), it may also be possible to work as a server that provides access to the contents of the memory card to all wireless devices connected to the modem. As for the types of cards, the most common support for the microSD standard is that they are small enough to be easily combined with compact wireless modem cases. Note that even within the same standard of memory cards there are several varieties, and before buying it's worth to clarify which of them the device is compatible with.
R-UIM card slot
The presence
of a slot for an R-UIM card in the modem design. The purpose of such cards is similar to the SIM cards described above, but they are used in networks based on CDMA (and, accordingly, in modems with EV-DO support, see "Transmission Technologies"). Note that, unlike devices for GSM and UMTS networks, for CDMA modems a slot for this type of card is not a mandatory element of equipment — many such devices are tied to the network by changing the firmware, which is why operators of such communication may not use R-UIM at all. Therefore, although in general the use of cards is simpler and more convenient for the user than flashing, however, the choice of the presence or absence of an R-UIM slot depends on the requirements of the network with which the modem is planned to be used.
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.
Operating time (standby)
The maximum time the modem can operate on battery power (see "Power") in standby mode on a single battery charge.
This mode can be described as the standby mode. It assumes that the device is turned on, its operating circuits are powered and ready to respond to an incoming signal or user command at any time, but no data exchange occurs and no features work. This indicator is not as important as the Internet browsing time (see above), but it is also of practical importance and allows you to evaluate the battery life of the device — after all, during breaks between communication sessions, the modem is in standby mode.