What is a Bandwidth Meter?

There are many fields of bandwidth application, which can be used to identify the data transmission capability of signal transmission, the amount of data passing through the link per unit time, and the display capability of the display.

The term bandwidth originally referred to the width of the electromagnetic wave band, which is the difference between the highest frequency and the lowest frequency of a signal. Currently, it is more widely borrowed in digital communications to describe the theoretically the highest rate at which data can be transmitted over a network or line. This is not its academic definition, but is used by extension ^[1]

In digital signal systems, the bandwidth is used to identify the ability of the communication line to transmit data, that is, the highest data rate through a point in the network in a unit time. , How many bits per second). Bps is often omitted when describing the bandwidth in daily life, for example: the bandwidth is 4M, and the complete title should be 4Mbps.

Aiming at the reduction of bandwidth cost, the user access rate is also getting higher and higher, from the initial dial-up Internet access to 20M or even 100M fiber.

But with the development of computers, users' awareness of 'bandwidth' should also be improved.

Generally speaking, the bandwidth is expressed in bits, and telecommunications, China Unicom, and mobile operators often ignore this unit when promoting.

The normal conversion is as follows:

1Mbit = 128KB

2Mbit = 256KB

(And so on)

The converted speed is your actual Internet speed

That is, if the bandwidth you have opened from your carrier is 10M, then plug it into the calculation formula and use the 1M converted above to measure

Then:

(1M = 1024K)

1M / 128K = 1024/128 = 8

10/8 = 1.25M

In other words, if you open a 10M bandwidth, you can reach a maximum speed of 1.25M.

Generally, a computer with 4M bandwidth is sufficient for watching movies, playing games, etc. But if you need to download large files frequently, it is recommended to use higher bandwidth

In analog signal systems, the bandwidth is used to identify the frequency width occupied by the transmission signal. This width is determined by the highest frequency and the lowest frequency of the transmission signal. The difference between the two is the bandwidth value, so it is also called the signal bandwidth or carrier frequency bandwidth. In Hz.

Bandwidth is actually a measure of the frequency spectrum occupied by a signal, which can be viewed as a spatially related quantity. In contrast, the signal transmission rate is a physical quantity related to both space and time, and is defined as the amount of data transmitted on the channel per unit time.

In order to use spectrum resources reasonably, the International Telecommunication Union (ITU) specifies a frequency range for each communication system. This frequency range is also called a frequency band, and the frequency band's spectrum width is also called the operating bandwidth. For example, the working bandwidth of GSM is 25 MHz, and both WCDMA and CDMA are 30 MHz.

The so-called "bandwidth" refers to the difference between the maximum value and the minimum value of each level of salary, and it becomes the distribution interval of salary value. Generally speaking, due to different job levels, the skills

When using a sinusoidal input to study the frequency dynamic characteristics of a sensor, the frequency characteristics and phase frequency characteristics are often used to describe the dynamic characteristics of the sensor. The important indicator is the frequency bandwidth, referred to as the bandwidth.

Bandwidth is the abbreviation of the passband width of the display video amplifier. It refers to the total number of pixels scanned by the electron gun in one second, that is, the scanning lines and fields (vertical) of all lines (horizontal direction) in a unit time Straight direction) Sum of the number of pixels displayed on the scan line, the unit is MHz.

Detailed calculation formula of bandwidth: B = r (x) × r (y) × V

• B indicates the bandwidth of the display

• r (x) represents the number of pixels on each horizontal scan line

• r (y) represents the number of horizontal scanning lines per frame

• V represents the frame refresh rate per second (ie field frequency)