Device and method for pre-treating a signal to be transmitted using a non-linear amplifier with an upstream band-pass filter

• US 20040014437A1
• Filed: 01/13/2003
• Published: 01/22/2004
• Est. Priority Date: 04/28/2000
• Status: Active Grant

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Gerhaeuser, Heinz, Perthold, Rainer
• Granted Patent: US 6,999,738 B2
• Time in Patent Office: Days
• US Class Current: 455/114.3
• CPC Class Codes: H03F 1/3247 using feedback acting on predistortion circuits H03F1/3264 takes precedence

Abstract

A device for pretreating a signal (S1) to be transmitted over a transmission path, wherein the transmission path comprises a band-pass filter (14) whose pass-band width is smaller than a predetermined bandwidth and a non-linear amplifier (16), includes a linearization means (20) for performing a linearization of the signal (S1) to be transmitted before the transmission of the same, such that a non-linearity caused by the non-linear amplifier (16) is counteracted. Further, the device includes a signal-shaping means (22) downstream to the linearization means (20) comprising a frequency response such that the overall frequency response of the signal-shaping means (22) and the band-pass filter (14) corresponds to the frequency response of a filter whose pass-band width is at least equal to the predetermined bandwidth.

Claims

1. A device for pretreating a signal to be transmitted over a transmission path, wherein the transmission path comprises a band-pass filter whose pass-band width is smaller than a predetermined bandwidth and a non-linear amplifier, comprising:

a linearizer for performing such a linearization of the signal to be transmitted before the transmission of the same, that a non-linearity caused by the non-linear amplifier is counteracted; and

a signal shaper downstream to the linearizer comprising such a frequency response that the overall frequency response of the signal shaper and the band-pass filter corresponds to the frequency response of a filter whose pass-band width is at least equal to the predetermined bandwidth.

2. The device according to claim 1, wherein the predetermined bandwidth corresponds to three times the signal bandwidth of the signal to be transmitted.

3. The device according to claim 1, wherein the linearizer and the signal shaper are arranged in the ground station of a satellite transmission system and wherein the band-pass filter and the non-linear amplifier are arranged in a satellite of the satellite transmission system.

4. The device according to claim 1, further comprising a receiver for receiving a signal to be transmitted over the transmission path and a means for setting coefficients of the linearization means and/or the signal-shaping means based on the received transmitted signal and the signal to be transmitted.

5. A method for transmitting a first signal over a transmission path comprising a band-pass filter whose pass-band width is less than a predetermined bandwidth, and a non-linear amplifier, comprising the following steps:

performing such a linearization of the first signal that a non-linearity caused by the non-linear amplifier is compensated for, in order to generate a second signal;

directing the second signal through a signal shaper comprising such a frequency response that the overall frequency response of the signal shaper and the band-pass filter corresponds to the frequency response of a filter whose pass-band width is at least equal to the predetermined bandwidth, in order to generate a third signal; and

transmitting the third signal over the transmission path.