What is carrier phase tracking in GPS?
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What is carrier phase tracking in GPS?
Carrier phase tracking is a highly accurate means of positioning used in GNSS surveying applications. The product of the period of the carrier frequency times the speed of light gives the wavelength, which is about 1900mm for the GPS L1 carrier.
What are GPS codes?
Each satellite has a unique pseudo-random code. The C/A code is the basis for civilian GPS use. The second pseudo-random code is called the P (Precise) code. It repeats on a seven day cycle and modulates both the L1 and L2 carriers at a 10MHz rate. This code is intended for military users and can be encrypted.
What are the differences between the code pseudorange and carrier phase?
Carrier phase measurements are similar to pseudorange in that they are the difference in phase between the transmitting and receiving oscillators. Integration of the oscillator frequency gives the clock time. The rate of change of phase is frequency. Notice that the phase difference changes as ρ/c changes.
What is carrier phase measurement?
Simply put, the carrier phase. measurement is a measure of the range between a satellite and receiver expressed in units of cycles of the carrier frequency.
What frequency does GPS use?
1575.42 MHz
All GPS satellites broadcast on at least two carrier frequencies: L1, at 1575.42 MHz, and L2, at 1227.6 MHz (newer satellites also broadcast on L5 at 1176 MHz).
What is cycle slip?
A cycle slip is a discontinuity in a receiver’s phase lock on a satellite’s signal. A power loss, a very low signal-to-noise ratio, a failure of the receiver software, a malfunctioning satellite oscillator can cause a cycle slip.
How does GPS code look like?
The two GPS codes are called coarse acquisition (or C/A-code) and precision (or P-code). Each code consists of a stream of binary digits, zeros and ones, known as bits or chips. The codes are commonly known as PRN codes because they look like random signals (i.e., they are noise-like signals).
What is the difference between range and pseudorange?
Range (sometimes referred to as true range) is an instantaneous measurement of the distance between the transmit antenna on the SV and receive antenna on the vehicle. Pseudorange is the range that a GNSS receiver measures between the transmit antenna on the SV and its’ receive antenna.
What is GPS delta range?
Pseudorange and delta-range are the basic measurements that a GPS receiver provides in an integrated GPS/inertial system. Usually the delta-range measurement is treated as an instantaneous velocity measurement in the Kalman filter integration of the two systems.
What is carrier phase shift?
The carrier phase shifted pulse width modulation carrier is a triangular wave, the phase shift angle of the triangle wave is related to the submodule position in the converter bridge arm. From: Unified Power Flow Controller Technology and Application, 2017.