Carrier Definitions for Land Surveyors

carrier[GPS]1Signal that can be varied from a known reference by modulation. 2 Radio wave with at least one characteristic (frequency, amplitude, phase) which can be varied from a known reference value by modulation.

Carrier-aided tracking [GPS]A signal processing strategy that uses the GPS carrier signal to achieve an exact lock on the pseudo random code. More accurate than standard approach.

Carrier beat phase [GPS]A phase of the signal which remains when the incoming Doppler-shifted satellite carrier signal is the beat (when the difference frequency signal is generated). See also beat frequency [GPS].

Carrier beat phase ambiguity [GPS]—The uncertainty in the initial measurement, which biases all measurements in an unbroken sequence. The ambiguity consists of three components: the fractional initial phase of the receiver, the fractional initial phase in the satellite (both due to various contributions to phase bias, such as unknown clock phase, circuit delays, etc.), and an integer cycle bias in the initial measurement.

Carrier frequency [GPS]The frequency of the unmodulated fundamental output of a radio transmitter.

carrier phase-1The phase of the L1 or L2 carrier signal that has accumulated since the GPS receiver locked onto the signal. 2 GPS measurements based on either of these signals.

Source: NSPS “Definitions of Surveying and Related Terms“, used with permission.

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