Справочник Пользователя для RoyalTek rgm-3000

 

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Phase Loss 
Count: 

The number of time the phase lock fell below the threshold between the 
present code phase sample and the previous code phase sample. This task is 
performed every 20 ms (max count is 50). 

Integration 
Interval: 

The time in ms for carrier phase accumulation . This is the time difference (as 
calculated by the user clock) between the Carrier Phase(current) and the 
Carrier Phase(previous). 

Track Loop 
Iteration: 

The tracking Loops are run at 2 ms and 10 ms intervals. Extrapolation values 
for each interval is 1 ms and 5 ms for range computations. 

 

The pseudo-range measurement in meters 

can be determined from the raw track data 

by solving the following equation: 

Pseudo-range (PR) = {Received Tine 

(RT) – Transmit Time (TT)} * C 

      where C = speed of light 

The following variables from the raw track 

data are required for each satellite: 

Bit Number (BN) – 50 bits per second 

Millisecond Number (MSN) 

Chip Number (CN) 

Code Phase (CP) 

Receiver Time Tag (RTTag) 

Delta Carrier Phase (DCP) 

The following steps are taken to get the psr 

data and carrier data for each measurement 

epoch. 

 

1.  Computation of initial Receiver 

Time(RT) in seconds. Note-Where the 

initial arbitrary value chosen at start 

up to make the PR reasonable 

(i.e.,set equal to TT+70ms) and then 

incriminated by one second for each 

measurement epoch. 

2.  Computation of Transmit Time (TT) in 

seconds. 

3.  Calculate Pseudo-range at a common 

receiver time of the first channel of 

the measurement data set. Note-All 

channel measurements are NOT 

taken at the same time. Therefore, all 

ranges must be extrapolated to a 

common measurement epoch. For 

simplicity, the first channel of each 

measurement set is used as the 

reference to which all other 

measurements are extrapolated. 

4.  Extrapolate the pseudo-range based 

on the correlation interval to improve 

precision. 

5.  Compute the delta range. 

If the accumulation time of the Dalta Carrier 

Phase is 1000 ms then the measurement is 

valid and can be added to the previous Delta 

Carrier Phase to get Accumulated Carrier 

Phase data. If the accumulation time of the 

Delta Carrier Phase is not equal to 1000 ms 

then the measurement is not valid and the 

accumulation time must be restarted to get 

Accumulated Carrier Phase data. 

Output Rate:Response to polling message 

Example: 

A0A20015 – Start Sequence and Payload 

Length 

0606312E322E30444B495431313920534

D0000000000-Payload 

0382B0B3 – Message Checksum and End 

Sequence