Browse Definitions :
Definition

bandpass filter

A bandpass filter is an electronic device or circuit that allows signals between two specific frequencies to pass, but that discriminates against signals at other frequencies. Some bandpass filters require an external source of power and employ active components such as transistors and integrated circuits; these are known as active bandpass filters. Other bandpass filters use no external source of power and consist only of passive components such as capacitors and inductors; these are called passive bandpass filters.

The illustration is an amplitude-vs-frequency graph, also called a spectral plot, of the characteristic curve of a hypothetical bandpass filter. The cutoff frequencies, f1 and f2, are the frequencies at which the output signal power falls to half of its level at f0, the center frequency of the filter. The value f2 - f1,expressed in hertz (Hz), kilohertz (kHz), megahertz (MHz), or gigahertz (GHz), is called the filter bandwidth. The range of frequencies between f1 and f2is called the filter passband.

Bandpass filters are used primarily in wireless transmitters and receivers. The main function of such a filter in a transmitter is to limit the bandwidth of the output signal to the minimum necessary to convey data at the desired speed and in the desired form. In a receiver, a bandpass filter allows signals within a selected range of frequencies to be heard or decoded, while preventing signals at unwanted frequencies from getting through. A bandpass filter also optimizes thesignal-to-noise ratio (sensitivity) of a receiver.

In both transmitting and receiving applications, well-designed bandpass filters, having the optimum bandwidth for the mode and speed of communication being used,maximize the number of signals that can be transferred in a system, while minimizing the interference or competition among signals.

This was last updated in November 2006
SearchCompliance
  • OPSEC (operations security)

    OPSEC (operations security) is a security and risk management process and strategy that classifies information, then determines ...

  • smart contract

    A smart contract is a decentralized application that executes business logic in response to events.

  • compliance risk

    Compliance risk is an organization's potential exposure to legal penalties, financial forfeiture and material loss, resulting ...

SearchSecurity
  • DOS (disk operating system)

    A DOS, or disk operating system, is an operating system that runs from a disk drive. The term can also refer to a particular ...

  • private key

    A private key, also known as a secret key, is a variable in cryptography that is used with an algorithm to encrypt and decrypt ...

  • security token

    A security token is a physical or digital device that provides two-factor authentication for a user to prove their identity in a ...

SearchHealthIT
SearchDisasterRecovery
  • What is risk mitigation?

    Risk mitigation is a strategy to prepare for and lessen the effects of threats faced by a business.

  • change control

    Change control is a systematic approach to managing all changes made to a product or system.

  • disaster recovery (DR)

    Disaster recovery (DR) is an organization's ability to respond to and recover from an event that affects business operations.

SearchStorage
  • What is RAID 6?

    RAID 6, also known as double-parity RAID, uses two parity stripes on each disk. It allows for two disk failures within the RAID ...

  • PCIe SSD (PCIe solid-state drive)

    A PCIe SSD (PCIe solid-state drive) is a high-speed expansion card that attaches a computer to its peripherals.

  • VRAM (video RAM)

    VRAM (video RAM) refers to any type of random access memory (RAM) specifically used to store image data for a computer display.

Close