Browse Definitions:
Definition

# phase

In electronic signaling, phase is a definition of the position of a point in time (instant) on a waveform cycle. A complete cycle is defined as 360 degrees of phase as shown in Illustration A below. Phase can also be an expression of relative displacement between or among waves having the same frequency .

Phase difference , also called phase angle , in degrees is conventionally defined as a number greater than -180, and less than or equal to +180. Leading phase refers to a wave that occurs "ahead" of another wave of the same frequency. Lagging phase refers to a wave that occurs "behind" another wave of the same frequency. When two signals differ in phase by -90 or +90 degrees, they are said to be in phase quadrature . When two waves differ in phase by 180 degrees (-180 is technically the same as +180), the waves are said to be in phase opposition . Illustration B shows two waves that are in phase quadrature. The wave depicted by the dashed line leads the wave represented by the solid line by 90 degrees.

Phase is sometimes expressed in radians rather than in degrees. One radian of phase corresponds to approximately 57.3 degrees. Engineers and technicians generally use degrees; physicists more often use radians.

The time interval for one degree of phase is inversely proportional to the frequency. If the frequency of a signal (in hertz ) is given by f , then the time t deg (in seconds) corresponding to one degree of phase is:

t deg = 1 / (360 f )

The time t rad (in seconds) corresponding to one radian of phase is approximately:

t rad = 1 / (6.28 f )

This was last updated in September 2005

#### Start the conversation

Send me notifications when other members comment.

## SearchCompliance

• ### PCAOB (Public Company Accounting Oversight Board)

The Public Company Accounting Oversight Board (PCAOB) is a Congressionally-established nonprofit that assesses audits of public ...

• ### cyborg anthropologist

A cyborg anthropologist is an individual who studies the interaction between humans and technology, observing how technology can ...

• ### RegTech

RegTech, or regulatory technology, is a term used to describe technology that is used to help streamline the process of ...

## SearchSecurity

• ### email spam

Email spam, or junk email, is unsolicited bulk messages sent through email with commercial, fraudulent or malicious intent.

• ### distributed denial of service (DDoS) attack

A distributed denial-of-service attack occurs when an attack originates from multiple computers or devices, usually from multiple...

• ### application whitelisting

Application whitelisting is the practice of identifying applications that have been deemed safe for execution and restricting all...

## SearchHealthIT

• ### athenahealth Inc.

Based in Watertown, Mass., athenahealth Inc. is a leading vendor of cloud-based EHRs for small to medium-sized physician ...

• ### Affordable Care Act (ACA or Obamacare)

The Affordable Care Act (ACA) is legislation passed in 2010 that changed how uninsured Americans enroll in and receive healthcare...

• ### HIPAA Privacy Rule

The Standards for Privacy of Individually Identifiable Health Information, commonly known as the HIPAA Privacy Rule, establishes ...

## SearchDisasterRecovery

• ### disaster recovery as a service (DRaaS)

One approach to a strong disaster recovery plan is DRaaS, where companies offload data replication and restoration ...

• ### data recovery

Data recovery restores data that has been lost, accidentally deleted, corrupted or made inaccessible. Learn how data recovery ...

• ### disaster recovery plan (DRP)

A company's disaster recovery policy is enhanced with a documented DR plan that formulates strategies, and outlines preparation ...

## SearchStorage

• ### virtual memory

Virtual memory is a memory management capability of an OS that allows a computer to compensate for physical memory shortages by ...

• ### yottabyte (YB)

A yottabyte is a measure of theoretical storage capacity and is 2 to the 80th power bytes, or, in decimal, approximately 1,000 ...

• ### Kilo, mega, giga, tera, peta, exa, zetta and all that

Kilo, mega, giga, tera, peta, exa, zetta are among the list of prefixes used to denote the quantity of something, such as a byte ...

## SearchSolidStateStorage

• ### 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.

• ### SSD caching

SSD caching, also known as flash caching, is the temporary storage of data on NAND flash memory chips in a solid-state drive so ...

• ### NVDIMM (Non-Volatile Dual In-line Memory Module)

An NVDIMM (non-volatile dual in-line memory module) is hybrid computer memory that retains data during a service outage.

## SearchCloudStorage

• ### RESTful API

A RESTful application program interface breaks down a transaction to create a series of small modules, each of which addresses an...

• ### cloud storage infrastructure

Cloud storage infrastructure is the hardware and software framework that supports the computing requirements of a private or ...

• ### Zadara VPSA and ZIOS

Zadara Storage provides block, file or object storage with varying levels of compute and capacity through its ZIOS and VPSA ...

Close