Amplifiers – With amplifier condition indicating or testing means
Patent
1997-11-05
1999-09-28
Mottola, Steven J.
Amplifiers
With amplifier condition indicating or testing means
330129, 341121, H03G 330, H03M 110
Patent
active
059594977
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention is based on a method for controlling the output of a transmission amplifier of a radio, in particular the transmission amplifier of a mobile phone, via a digital/analog converter.
2. Prior Art
From "European digital cellular telecommunications system" (Phase 2); Radio transmission and reception (GSM 05.05) of the European Telecommunications Standards Institute of May 1994, it is known that data are transmitted in time-layered multiplexing in mobile phones; that is, that transmission operations take place only during certain time slots, in so-called bursts. The output of the transmission amplifier is raised to the requisite value only for the actual transmission operation, in accordance with a specified time function. Both for the course of a time and for the final value of the transmission output, a narrow tolerance range is prescribed, so that high demands for accuracy and freedom from offset are made of the digital/analog converter by means of which the transmission amplifier output is controlled.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an improved method for control of the output of a transmission amplifier of a radio, especially a mobile phone, via a digital/analog converter.
It is another object of the present invention to provide an improved method for control of the output of a transmission amplifier of a radio which does not place high demands for accuracy and freedom from offset.
The method of the invention makes it possible by comparison to precisely control the output of the transmission amplifier of a radio device via conventional digital/analog converters, of which no particular demands for freedom from offset are made. This is advantageously attained in that the offset of the digital/analog converter is measured during transmission pauses and taken into account in the ensuing transmission operation as a correction variable in the triggering of the digital/analog converter.
It is also advantageous to amplify the signal, output by the digital/analog converter in transmission pauses in the context of test cycles, before evaluation, so that particularly for low values of the offset high resolution in its determination is achieved. Moreover, as a result adulteration in the determination of the offset from an additional offset of the analog/digital converter for reconversion of the analog signal into a digital signal can be largely ignored.
Finally, it is advantageous if the offsets of the circuit stages involved in ascertaining the offset of the digital/analog converter are known, so that these adulterations can be taken into account in the form of correction values.
If the offset of the digital/analog converter is essentially dependent on the ambient temperature, then the value of the offset can also be used to compensate for the temperature drift of other components.
BRIEF DESCRIPTION OF THE DRAWING
An exemplary embodiment of the invention is shown in the drawing and described in further detail in the ensuing description. The drawing schematically shows a layout for performing the method of the invention; for the sake of simplicity, only the function blocks essential to the invention are shown.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The method of the invention will be described below taking as an example mobile phones operated by the GSM standard, but in principle it is not limited to this application but instead can be expanded to radio devices in general.
In the exemplary embodiment, shown in the drawing, of a circuit arrangement for performing the method of the invention, an evaluation and control unit 1 is connected to a signal generator 2 via a data line. The signal generator 2 triggers the digital/analog converter 3, whose output signal is delivered on the one hand to the transmission amplifier 4 and on the other to an amplifier 5, which in turn is connected to an analog/digital converter associated with the evaluation and control unit 1. In addition, a control signal for ad
REFERENCES:
patent: 4926360 (1990-05-01), Spink
patent: 5194822 (1993-03-01), Bureau et al.
patent: 5381148 (1995-01-01), Mueck et al.
patent: 5731772 (1998-03-01), Mikkola et al.
European Digital Cellular Telecommunications System (Phase 2); Radio Transmission And Reception (GSM 05.05), European Telecommunications Standards Institute, May 1994.
Mottola Steven J.
Robert & Bosch GmbH
Striker Michael J.
LandOfFree
Process for controlling the power of the transmission amplifier does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for controlling the power of the transmission amplifier , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for controlling the power of the transmission amplifier will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-707806