Browse Definitions :
Definition

omnidirectional antenna

An omnidirectional antenna is a wireless transmitting or receiving antenna that radiates or intercepts radio-frequency (RF) electromagnetic fields equally well in all horizontal directions in a flat, two-dimensional (2D) geometric plane. Omnidirectional antennas are used in most consumer RF wireless devices, including cellular telephone sets and wireless routers.

In theory, a vertically oriented, straight conductor such as a dipole antenna measuring no more than 1/2 wavelength from end-to-end always exhibits omnidirectional properties in a horizontal (azimuth) plane. Multiple collinear (in-line) vertical dipoles also exhibit omnidirectional behavior in the azimuth plane; they can offer improved performance over a single dipole in some applications. If the conductor axis is not oriented vertically, then the antenna radiates and receives equally well in all directions in the plane through which the conductor passes at a right angle. However, this ideal state of affairs exists only in the absence of obstructions or other nearby conducting objects. In practice, surrounding objects (such as the user of a cell phone set or a computer next to a wireless router) distort the radiation and reception pattern.

In the usual context, a so-called omnidirectional antenna does not perform equally well in all possible directions in three-dimensional (3D) space. Such a device, which can exist only in theory but can be approached in practice, is called an isotropic antenna or isotropic radiator.

Antennas that offer enhanced performance in some directions, at the expense of other directions, are called directional antennas or directional radiators. The most common example is the dish antenna used with satellite internet, satellite television, and space-communications installations. Other examples include the Yagi antenna, quad antenna, billboard antenna, and helical antenna.

 

This was last updated in December 2016

Continue Reading About omnidirectional antenna

SearchNetworking
  • cloud-native network function (CNF)

    A cloud-native network function (CNF) is a service that performs network duties in software, as opposed to purpose-built hardware.

  • Wi-Fi 6E

    Wi-Fi 6E is one variant of the 802.11ax standard.

  • microsegmentation

    Microsegmentation is a security technique that splits a network into definable zones and uses policies to dictate how data and ...

SearchSecurity
  • MICR (magnetic ink character recognition)

    MICR (magnetic ink character recognition) is a technology invented in the 1950s that's used to verify the legitimacy or ...

  • What is cybersecurity?

    Cybersecurity is the protection of internet-connected systems such as hardware, software and data from cyberthreats.

  • Android System WebView

    Android System WebView is a system component for the Android operating system (OS) that allows Android apps to display web ...

SearchCIO
  • privacy compliance

    Privacy compliance is a company's accordance with established personal information protection guidelines, specifications or ...

  • contingent workforce

    A contingent workforce is a labor pool whose members are hired by an organization on an on-demand basis.

  • product development (new product development -- NPD)

    Product development, also called new product management, is a series of steps that includes the conceptualization, design, ...

SearchHRSoftware
  • talent acquisition

    Talent acquisition is the strategic process employers use to analyze their long-term talent needs in the context of business ...

  • employee retention

    Employee retention is the organizational goal of keeping productive and talented workers and reducing turnover by fostering a ...

  • hybrid work model

    A hybrid work model is a workforce structure that includes employees who work remotely and those who work on site, in a company's...

SearchCustomerExperience
  • Salesforce Trailhead

    Salesforce Trailhead is a series of online tutorials that coach beginner and intermediate developers who need to learn how to ...

  • Salesforce

    Salesforce, Inc. is a cloud computing and social enterprise software-as-a-service (SaaS) provider based in San Francisco.

  • data clean room

    A data clean room is a technology service that helps content platforms keep first person user data private when interacting with ...

Close