US-12621015-B2 - Receiver path for a measurement device and measurement device comprising such a receiver path

Abstract

A receiver path for a measurement device is provided. Said receiver path comprises a radio frequency input path for inputting a radio frequency input signal, a mixer for generating an intermediate frequency signal by mixing the radio frequency input signal with a local oscillator signal, and an intermediate frequency signal carrying path for carrying the intermediate frequency signal. In this context, the intermediate frequency signal carrying path comprises a voltage variable attenuator.

Inventors

• Alexander DORER
• Matthias LUTZ

Assignees

• ROHDE & SCHWARZ GMBH & CO. KG

Dates

Publication Date

20260505

Application Date

20220928

Claims (19)

1. 1 . A receiver path for a measurement device, the receiver path comprising: a radio frequency input path for inputting a radio frequency input signal, a mixer for generating an intermediate frequency signal by mixing the radio frequency input signal with a local oscillator signal, and an intermediate frequency signal carrying path for carrying the intermediate frequency signal, wherein the intermediate frequency signal carrying path comprises a voltage variable attenuator, wherein the voltage variable attenuator is adapted to change its attenuation to compensate ambient temperature changes with respect to printed circuit boards associated with the measurement device.
2. 2 . The receiver path according to claim 1 , wherein the radio frequency input path comprises: at least one preselector, preferably at least one filter, and/or at least one attenuator, and/or at least one amplifier.
3. 3 . The receiver path according to claim 2 , wherein the at least one preselector, preferably the at least one filter, is switchable, and/or wherein the at least one attenuator is switchable, and/or wherein the at least one amplifier is switchable.
4. 4 . The receiver path according to claim 1 , wherein the intermediate frequency signal carrying path further comprises: at least one amplifier, and/or at least one attenuator.
5. 5 . The receiver path according to claim 1 , wherein the intermediate frequency signal carrying path is adapted to feed the intermediate frequency signal into an analog-to-digital converter or into an analog-digital-converter through a filter, preferably an anti-aliasing filter.
6. 6 . The receiver path according to claim 5 , wherein the intermediate frequency signal carrying path comprises the analog-to-digital converter and/or the filter, preferably the anti-aliasing filter.
7. 7 . The receiver path according to claim 5 , wherein the intermediate frequency signal carrying path is adapted to feed the intermediate frequency signal into the analog-to-digital converter through the voltage variable attenuator or into the filter, preferably the anti-aliasing filter, through the voltage variable attenuator.
8. 8 . The receiver path according to claim 1 , wherein the voltage variable attenuator is adapted to change its attenuation in a continuous manner.
9. 9 . The receiver path according to claim 1 , wherein the voltage variable attenuator is adapted to increase its attenuation if an ambient temperature, preferably the temperature with respect to print circuit boards associated with the measurement device, decreases.
10. 10 . The receiver path according to claim 1 , wherein the voltage variable attenuator is adapted to decrease its attenuation an ambient temperature, preferably the temperature with respect to print circuit boards associated with the measurement device, increases.
11. 11 . The receiver path according to claim 1 , wherein the measurement device is provided with at least one ambient sensor, preferably at least one ambient temperature sensor.
12. 12 . The receiver path according to claim 1 , wherein the measurement device is adapted to estimate ambient temperature changes on the basis of temperature changes with respect to the printed circuit boards associated with the measurement device.
13. 13 . The receiver path according to claim 1 , wherein the voltage variable attenuator comprises or is a positive intrinsic negative diode.
14. 14 . The receiver path according to claim 13 , wherein the positive intrinsic negative diode comprises or is a positive intrinsic negative diode with bias current or a positive intrinsic negative diode with bias voltage.
15. 15 . A receiver path for a measurement device, the receiver path comprising: a radio frequency input path for inputting a radio frequency input signal, a mixer for generating an intermediate frequency signal by mixing the radio frequency input signal with a local oscillator signal, and an intermediate frequency signal carrying path for carrying the intermediate frequency signal, wherein the intermediate frequency signal carrying path comprises a voltage variable attenuator, wherein the voltage variable attenuator is adapted to change its attenuation to compensate ambient temperature changes with respect to printed circuit boards associated with the measurement device, wherein the voltage variable attenuator is designed on the basis of temperature characteristics of at least one amplifier of the receiver associated with the measurement device.
16. 16 . The receiver path according to claim 15 , wherein the temperature characteristics are obtained on the basis of measurements in a climate cabinet, wherein the voltage variable attenuator is preferably held constant.
17. 17 . A measurement device comprising: a receiver path according to any preceding claims .
18. 18 . The measurement device according to claim 17 , wherein the measurement device further comprises: at least one ambient sensor, preferably at least one ambient temperature sensor.
19. 19 . The measurement device according to claim 17 , wherein the measurement device is adapted to estimate ambient temperature changes on the basis of temperature changes with respect to the printed circuit boards associated with the measurement device.

Description

TECHNICAL FIELD The invention relates to a receiver path, especially a receiver path with compensation of gain over temperature, for a measurement device, and a measurement device comprising such a receiver path. BACKGROUND ART Generally, in times of an increasing number of applications providing radio frequency capabilities, there is a growing need of a receiver path for a measurement device and a measurement device comprising such a receiver path for performing radio frequency measurements with respect to a device under test comprising such an application in order to verify correct functioning of said applications in a highly accurate and efficient manner. In this context of testing, common measurement devices, especially common measurement devices with common receiver paths, for performing radio frequency measurements have always the problem of inaccuracies and inefficiencies in the case of temperature changes during measuring due to a temperature dependence of at least some parts of the corresponding receiver path. For instance, IN 201841035757 A discloses an up-down converter comprising radio frequency blocks, wherein at least one of the radio frequency blocks comprises at least one voltage variable attenuator to prevent the receiver from getting saturated. Disadvantageously, such a configuration does not allow for fully compensating temperature changes in a particularly efficient manner. Furthermore, an example of a voltage variable attenuator is shown by the “F2270 Datasheet” of Renesas Electronics America Inc. In addition to this, EP 3 211 792 A1 provides apparatus and methods for high linearity voltage variable attenuators. Moreover, US 2009/0046607 A1 discloses an apparatus and a method for controlling automatic gain in a wireless communication system using a Time Division Duplex scheme. Accordingly, there is a need to provide a receiver path for a measurement device and a measurement device comprising such a receiver path, whereby both a high accuracy and a high efficiency are ensured. SUMMARY OF THE INVENTION According to a first aspect of the invention, a receiver path for a measurement device is provided. Said receiver path comprises a radio frequency input path for inputting a radio frequency input signal, a mixer for generating an intermediate frequency signal by mixing the radio frequency input signal with a local oscillator signal, and an intermediate frequency signal carrying path for carrying the intermediate frequency signal. In this context, the intermediate frequency signal carrying path comprises a voltage variable attenuator. Advantageously, this allows for a consistently high level accuracy with temperature fluctuations in a particularly efficient manner. Further advantageously, for instance, there is no need to readjust the corresponding gain in case of temperature fluctuations, which also leads to no need to restart the measurement, thereby ensuring a particularly high efficiency. According to a first preferred implementation form of the first aspect of the invention, the radio frequency input path comprises at least one preselector, preferably at least one filter, and/or at least one attenuator, and/or at least one amplifier. Advantageously, for example, complexity can be reduced, which leads to an increased efficiency. According to a second preferred implementation form of the first aspect of the invention, the at least one preselector, preferably the at least one filter, is switchable, and/or the at least one attenuator is switchable, and/or the at least one amplifier is switchable. Advantageously, for instance, a high flexibility can be ensured, thereby allowing for a high efficiency. According to a further preferred implementation form of the first aspect of the invention, the intermediate frequency signal carrying path further comprises at least one amplifier, and/or at least one attenuator. Advantageously, for example, simplicity can be increased, which leads to an increased efficiency. According to a further preferred implementation form of the first aspect of the invention, the intermediate frequency signal carrying path is adapted to feed the intermediate frequency signal into an analog-to-digital converter or into an analog-digital-converter through a filter, preferably an anti-aliasing filter. Advantageously, for instance, best possible Error Vector Magnitude (EVM) performance can be achieved especially due to an optimum modulation of the analog-to-digital converter, thereby ensuring a particularly high accuracy and efficiency. Further advantageously, the signal-to-noise ratio can be increased, which also leads to reduced inaccuracies and inefficiencies. According to a further preferred implementation form of the first aspect of the invention, the intermediate frequency signal carrying path comprises the analog-to-digital converter and/or the filter, preferably the anti-aliasing filter. Advantageously, for example, the receiver path can be built as a subassembly being