Browse Definitions :
Definition

pulse amplitude modulation (PAM)

Pulse amplitude modulation (PAM) is the transmission of data by varying the amplitude s ( voltage or power levels) of the individual pulses in a regularly timed sequence of electrical or electromagnetic pulses. The number of possible pulse amplitudes can be infinite (in the case of analog PAM), but it is usually some power of two so that the resulting output signal can be digital . For example, in 4-level PAM there are 2^2  possible discrete pulse amplitudes; in 8-level PAM there are 2^3 possible discrete pulse amplitudes; and in 16-level PAM there are 2^4 possible discrete pulse amplitudes.

In some PAM systems, the amplitude of each pulse is directly proportional to the instantaneous modulating-signal amplitude at the time the pulse occurs. In other PAM systems, the amplitude of each pulse is inversely proportional to the instantaneous modulating-signal amplitude at the time the pulse occurs. In still other systems, the intensity of each pulse depends on some characteristic of the modulating signal other than its strength, such as its instantaneous frequency or phase .

PAM is only one of several forms of pulse modulation. Other methods include varying the durations (or widths), the frequencies, the positions, or the intervals of the individual pulses in a sequence.

This was last updated in March 2011

SearchCompliance

  • information governance

    Information governance is a holistic approach to managing corporate information by implementing processes, roles, controls and ...

  • enterprise document management (EDM)

    Enterprise document management (EDM) is a strategy for overseeing an organization's paper and electronic documents so they can be...

  • risk assessment

    Risk assessment is the identification of hazards that could negatively impact an organization's ability to conduct business.

SearchSecurity

  • spam trap

    A spam trap is an email address that is used to identify and monitor spam email.

  • honeypot (computing)

    A honeypot is a network-attached system set up as a decoy to lure cyber attackers and detect, deflect and study hacking attempts ...

  • cracker

    A cracker is someone who breaks into someone else's computer system, often on a network; bypasses passwords or licenses in ...

SearchHealthIT

SearchDisasterRecovery

  • risk mitigation

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

  • call tree

    A call tree is a layered hierarchical communication model that is used to notify specific individuals of an event and coordinate ...

  • Disaster Recovery as a Service (DRaaS)

    Disaster recovery as a service (DRaaS) is the replication and hosting of physical or virtual servers by a third party to provide ...

SearchStorage

  • cloud storage

    Cloud storage is a service model in which data is transmitted and stored on remote storage systems, where it is maintained, ...

  • cloud testing

    Cloud testing is the process of using the cloud computing resources of a third-party service provider to test software ...

  • storage virtualization

    Storage virtualization is the pooling of physical storage from multiple storage devices into what appears to be a single storage ...

Close