Apparatus and method for compensating optical transmission delay
The present invention provides a method of optical transmission delay compensation of a system including a main unit and a remote unit, wherein the main unit and the remote unit are connected to each other through an optical transmission line, including: receiving a reference signal, by the remote unit, generated by the main unit through the optical transmission line; analog converting the reference signal and performing analog processing on the reference signal; converting the analog-processed reference signal into an RF signal and radiating the RF signal; and measuring a delay time until the reference signal is generated and radiated as the RF signal. Accordingly, it is possible to obtain an effect of preventing degradation of service quality due to interference by synchronizing remote units and improving the service quality.
1. A method of transmission delay compensation of a system including a main unit and a remote unit connected to the main unit through a transmission line, the method comprising:
receiving a reference signal and a first GPS signal from the main unit at the remote unit;
performing a signal processing on the reference signal for radiating at the remote unit;
receiving a second GPS signal at the remote unit, and
measuring a delay time until the reference signal is generated and processed for radiating based on the first GPS signal and the second GPS signal at the remote unit.
2. The method of claim 1 , wherein the signal processing comprises at least one of digital-to-analog conversion, noise removal and amplification.
3. The method of claim 1 , wherein the reference signal is a plurality of signals having different phases from each other,
the remote unit generates a synchronization detection window, and
the measuring of the delay time comprises:
measuring the delay time by detecting one of the signals using the synchronization detection window.
4. The method of claim 1 , wherein the remote unit generates a plurality of synchronization detection windows, and
the measuring of the delay time comprises:
measuring the delay time by using a window for detecting the reference signal among the plurality of synchronization detection windows.
5. The method of claim 1 , further comprising:
transmitting the delay time to the main unit at the remote unit; and
compensating for a data signal by the delay time at the main unit.
6. The method of claim 1 , further comprising:
receiving a data signal from the main unit at the remote unit; and
compensating for the data signal by the delay time at the remote unit.
7. The method of claim 1 , wherein the measuring of the delay time further comprises:
generating a response signal corresponding to a time when the signal processing is terminated at the remote unit;
transmitting the response signal to the main unit at the remote unit;
measuring the delay time using the response signal at the main unit.
8. A system comprising:
a main unit; and
a plurality of remote units connected to the main unit through a transmission line,
wherein at least one of the plurality of remote unit comprises:
a signal processor configured to perform a signal processing on a reference signal received from the main unit for radiating;
a GPS receiver configured to receive a GPS signal; and
a delay time processor configured to measure a delay time until the reference signal is generated and processed using the GPS signal.
9. The system of claim 8 , wherein the signal processing comprises at least one of digital-to-analog conversion, noise removal and amplification.
10. The system of claim 8 , wherein the reference signal is a plurality of signals having different phases from each other, and
the delay time processor is configured to:
generate a synchronization detection window; and
measure the delay time by detecting one of the signals using the synchronization detection window.
11. The system of claim 8 , wherein the delay time processor is configured to:
generate a plurality of synchronization detection windows, and
measure the delay time by using a window for detecting the reference signal among the plurality of synchronization detection windows.
12. The system of claim 8 , wherein the delay time processor is configured to transmit the delay time to the main unit.
13. The system of claim 12 , wherein the main unit compensates for a data signal by the delay time.
14. The system of claim 8 , wherein the delay time processor is configured to compensate for a data signal received from the main unit by the delay time.