telecommunication Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...

, the term frequency frogging has the following meanings: # The interchanging of the frequencies of carrier channels to accomplish specific purposes, such as to prevent feedback and oscillation, to reduce crosstalk, and to correct for a high

frequency response In signal processing and electronics, the frequency response of a system is the quantitative measure of the magnitude and phase of the output as a function of input frequency. The frequency response is widely used in the design and analysis of s ...

slope in the

transmission line In electrical engineering, a transmission line is a specialized cable or other structure designed to conduct electromagnetic waves in a contained manner. The term applies when the conductors are long enough that the wave nature of the transmi ...

. # In microwave radio relay systems, the alternate use of two frequencies at repeater sites to prevent feedback and oscillation. ''Note:''

Frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...

frogging is accomplished by having

modulator In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the ''carrier signal'', with a separate signal called the ''modulation signal'' that typically contains informatio ...

s, which are integrated into specially designed

repeater In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Som ...

s, translate a low-frequency

group A group is a number of persons or things that are located, gathered, or classed together. Groups of people * Cultural group, a group whose members share the same cultural identity * Ethnic group, a group whose members share the same ethnic ide ...

to a high-frequency group, and vice versa. A

frequency channel In broadcasting, a channel or frequency channel is a designated radio frequency (or, equivalently, wavelength), assigned by a competent frequency assignment authority for the operation of a particular radio station, television station or televis ...

will appear in the low group for one

section and will then be translated to the high group for the next section because of frequency frogging. This results in nearly constant

attenuation In physics, attenuation (in some contexts, extinction) is the gradual loss of flux intensity through a medium. For instance, dark glasses attenuate sunlight, lead attenuates X-rays, and water and air attenuate both light and sound at variabl ...

with frequency over two successive repeater sections, and eliminates the need for large slope equalization and adjustments.

Singing Singing is the act of creating musical sounds with the voice. A person who sings is called a singer, artist or vocalist (in jazz and/or popular music). Singers perform music (arias, recitatives, songs, etc.) that can be sung with or with ...

and crosstalk are minimized because the high-level output of a

is at a different frequency than the low-level input to other repeaters. It also diminishes

group delay In signal processing, group delay and phase delay are delay times experienced by a signal's various frequency components when the signal passes through a system that is linear time-invariant (LTI), such as a microphone, coaxial cable, amplifie ...

distortion. A repeater that receives on the high band from both direction and sends on the low band is called Hi-Lo; the other kind Lo-Hi.

References

{{FS1037C MS188 Communication circuits