Tuning a station
View Patent ↗A method of tuning a station is disclosed, wherein a first pilot signal is applied on a circuit of the station and the resulting output power of the signal circuit is subsequently detected. A second pilot signal is then applied to the circuit and the resulting output power of the circuit is detected. The offset of the circuit is then tuned based on information of the resulting output power detected for the first and second signals. A station that is adapted to implement the method may be tuned by the manufacturer thereof or later after having already been taken into use. The tuning may occur automatically as response to a predefined event.
1. A method of tuning a station, the method comprising:
a) applying a first signal to a first input of a circuit of the station and subsequently detecting the resulting output power of said circuit;
b) applying a second signal to said first input of said circuit and subsequently detecting the resulting output power of said circuit, said second signal being provided by changing the polarity of the first signal; and
c) compensating an offset of the circuit based on information of the resulting output power detected in steps a) and b);
wherein the circuit includes at least the first input and at least one component is provided for subjecting a signal applied to said first input to an offset correction.
2. The method of claim 1 , wherein steps a) to c) are repeated at least once.
3. The method of claim 1 , wherein the signal comprises a reference voltage.
4. The method of claim 2 , wherein the signal comprises a reference voltage.
5. The method of claim 1 , wherein said signal is a pilot signal.
6. The method of claim 2 , wherein said signal is a pilot signal.
7. The method of claim 3 , wherein said signal is a pilot signal.
8. The method of claim 1 , wherein the offset is tuned until substantially equal resulting output power is detected subsequent to the application of said first and second signals.
9. The method of claim 1 , wherein the output power comprise output power of modulator means of the circuit.
10. The method of claim 1 , wherein the tuning is accomplished based on the difference determined for the resulting output power in steps a) and b).
11. The method of claim 1 , wherein the circuit comprises at least one of an in-phase (I) branch and a quadrature phase (Q) branch of an IQ modulator for a transmitter.
12. The method of claim 11 , wherein the steps a) to c) are applied at least once for both of said in-phase and quadrature branches.
13. The method of claim 1 , wherein the output power are detected by envelope detector means.
14. The method of claim 1 , wherein the tuning is based on information regarding detected carrier leakage in the station.
15. The method of claim 1 , wherein at least one further error is compensated by tuning the station.
16. The method of claim 1 , wherein the tuning is controlled by a digital signal processor.
17. The method of claim 1 , wherein the station comprises a mobile station of a cellular communication system.
18. The method of claim 17 , wherein the tuning is accomplished during the manufacture of the mobile station.
19. The method of claim 17 , wherein the tuning is accomplished in response to an event after the mobile station has been taken in use.
20. The method of claim 18 , wherein the tuning is accomplished in response to an event after the mobile station has been taken in use.
21. The method of claim 19 , wherein the event comprises one of: expiry of a predefined time period; change in the operational status of the station; change in the operation environment of the station; a message from another station; action taken by the user.
22. The method of claim 20 , wherein the event comprises one of: expiry of a predefined time period; change in the operational status of the station; change in the operation environment of the station; a message from another station; action taken by the user.
23. The method of claim 19 , wherein the tuning is triggered automatically in response to the event.
24. The method of claim 20 , wherein the tuning is triggered automatically in response to the event.
25. The method of claim 21 , wherein the tuning is triggered automatically in response to the event.
26. The method of claim 22 , wherein the tuning is triggered automatically in response to the event.
27. The method of claim 1 , wherein the first pilot signal is selected such that the tuning of the station does not substantially interfere with the operation of other stations.
28. The method of claim 1 , wherein said offset is an DC offset.
29. The method of claim 1 , wherein said offset is a gain offset.
30. A station comprising:
a modulator circuit including at least a first input and at least one component for subjecting a signal applied to said first input to an offset correction;
signal means for applying signals to a said first input of said modulator circuit of the station, said signal means being adapted to change the polarity of a first signal to produce a second signal;
detector means for detecting resulting output power of said modulator circuit; and
means for tuning the offset of the modulator circuit based on information of said output power detected by the detector means.
31. The station of claim 30 , wherein the station comprises a mobile station for communication via a cellular communication system.
32. The station of claim 30 , wherein the modulator circuit comprises at least one of an in-phase (I) signal branch and a quadrature phase (Q) signal branch.
33. The station of claim 31 , wherein the modulator circuit comprises at least one of an in-phase (I) signal branch and a quadrature phase (Q) signal branch.
34. The station of claim 30 , wherein the detector means comprise an envelope detector.
35. The station of claim 31 , wherein the detector means comprise an envelope detector.
36. The station of claim 32 , wherein the detector means comprise an envelope detector.
37. The station of claim 33 , wherein the detector means comprise an envelope detector.
38. The station of claim 30 , further comprising a digital signal processor adapted for controlling the tuning of the station.
39. The station of claim 31 , further comprising a digital signal processor adapted for controlling the tuning of the station.
40. The station of claim 32 , further comprising a digital signal processor adapted for controlling the tuning of the station.
41. The station of claim 33 , further comprising a digital signal processor adapted for controlling the tuning of the station.
42. The station of claim 34 , further comprising a digital signal processor adapted for controlling the tuning of the station.
43. The station of claim 35 , further comprising a digital signal processor adapted for controlling the tuning of the station.
44. The station of claim 36 , further comprising a digital signal processor adapted for controlling the tuning of the station.
45. The station of claim 37 , further comprising a digital signal processor adapted for controlling the tuning of the station.
46. The station of claim 30 , wherein the station is adapted to tune itself in response to an event.
47. The station of claim 46 , wherein the event comprises one of: expiry of a predefined time period; change in the operational status of the station; change in the operation environment of the station; a message from another station; and action taken by the user of the station.
48. The method of claim 1 , further comprising:
d) compensating phase offset of the circuit based on information of the resulting output power detected in steps a) and b).
49. The method of claim 48 , wherein said circuit comprises first and second parts including first and second inputs and respective first and second components for subjecting signals applied to said first and second inputs to offset corrections, said first signal being applied to said first and second input and said second signal being applied to at least one of said first and second input.
50. The method of claim 49 , further comprising the step of calibrating said phase offset so that different amounts of predistortion are added to said first and second parts of said circuit.
51. The station of claim 30 , further comprising:
means for tuning a phase offset of the modulator circuit based on information of said output power detected by the detector means.