The Modem also has many types with advantages and disadvantages respectively. In this article, it will be discussed about the understanding of modems, modem functions, modem types, and how the modem works.
Definition of Modem
The MODEM itself is an acronym of the Demodulator Modulator. This means that the device can function as a modulator and also a demodulator. The modulator itself means that the information signal modifier becomes the signal of the carrier to send.
Meanwhile, the demodulator is a separator between the information signal and the carrier signal, so that a data can be received perfectly. Broadly, the modem can be divided into two types, the internal modem and the external modem. The explanation of the two is shown in the following points:
1. Internal Modem
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| Modem internal (PCI modem) |
As the name suggests, the internal modem is a type of modem that is installed directly in the CPU of a computer. If noted, the shape of a card is placed in one of the mainboard expansion slots, e.g. in a PCI or ISA slot. Some of the advantages of using an internal modem are that it is more efficient, it doesn't require many places, and it doesn't need an adaptor, making it more practical.
However, using the built-in modem will not be able to see indicators indicating the status of the modem with the naked eye. The internal Modem must also supply the power voltage from the CPU, as it is connected with the device.
2. External Modem
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| External modem (USB modem) |
It is a type of modem that is located outside the CPU. Usually to connect this modem with a computer, done via USB port or COM. One of the advantages of using an external modem is that it is flexible enough to moveable from one computer to another.
In addition, there is no need for expansion slots that are Dijatahkan specific to the modem. There are also indicators that make users understand and can monitor the status of the modem. However, the external modem is more expensive than the internal modem and requires its own place to put it, although it does not require such a wide space. There is a wide range of external modems on the market. If viewed from a wireless network system, for example, there are external modems such as GSM modem, CDMA modem, HDSPA modem, and HSUPA modem.
Modem function
The Modem has several functions for a computer to be connected to the Internet network. In general, a modem does have the main function of converting a digital signal from a computer into an analog signal and vice versa, but the modem also has other functions. The functions of the modem include:
- Change digital signal to analog and vice versa
- Connect a device (computer, laptop, etc.) to the network
- Translating signals with modulation and demodulation processes
- Check your data plan to communicate
Types of modems
As mentioned earlier, there are different types of modems that you need to know, for example:
- Dial-up Modem: To connect the computer and Internet network via telephone cable. It is internal and installed directly on the motherboard. When used, users can not use the phone temporarily. The access speed is only 12-20 Kbps, but almost all PCS and laptops have a dial-up modem.
- Cable modem: A modem that can connect a computer with a cable TV connection. Download speeds can reach 27 Mbps and upload speeds can reach an upstream of 2.5 Mbps. Internet services are usually not restricted and payments are made every month. While the modem is somewhat expensive, the speed of access is not affected by peak hours.
- GSM Modem: A modem that requires a GSM Simcard card to work. Includes an external modem that must be mounted to a computer port. Usually many people use this modem for his laptop. Previously, a simcard must be filled with credit or data plan in advance to be connected to the Internet. GSM Modem has a wide network coverage, only the user can spend a fairly expensive subscription fee per month.
- CDMA Modem: A wireless Modem that works on a CDMA network, allowing more than one signal to occupy a single transmission channel, thereby optimizing the existing bandwidth. The difference with GSM (which uses TDMA channels), CDMA does not peg a certain frequency for its users. Each channel can use an existing full spectrum. CDMA modem prices are more expensive than GSM, but cellular communication lines and data are separate, making connectivity more stable.
How the Modem works
The Modem itself is actually a tool that allows one computer with another computer to communicate by translating the signal emitted. The computer as a hardware emits a type of digital signal, a signal capable of generating the display of images, documents, or programs. Meanwhile, Internet channels over the phone are devices that work with the type of analog signal.
The digital signal that the computer sends must first be converted into an analog signal, so that it can be through the telephone line. As previously mentioned, the modem stands for the demodulator modulator. Modulation is the process of translating digital signals into analog, while demodulation is the process of translating analog signals into digital.
Such is the discussion about the understanding of modems, modem functions, and how the modem works. There are quite a few types of modems available on the market. Use it again to your needs. By weighing the advantages and disadvantages of each, you can determine what modem is the most optimal to connect your PC to the Internet network.
