USB Preamplifiers U7227/8A/8C/8F

USB Preamplifiers

U7227/8A 10 MHz to 4 GHz

U7227/8C 100 MHz to 26.5 GHz

U7227/8F 2 to 50 GHz

Key Features and Benefits

•  Automatic gain correction value with temperature compensation and transfer of calibration data (noise figure and S-parameters) through USB plug and play features for improved noise figure measurements with Keysight N9040/1B UXA and N9010/20/30A/B X-Series signal analyzers
•  Excellent noise figure and optimized gain with the X-Series signal analyzers; improves measurement accuracy and minimizes uncertainty
•  Provides ultra-broadband operating frequency from 10 MHz up to 50 GHz for various applications
•  Rugged and portable design for benchtop measurements or remote front-end applications

Benchtop/Remote Front End Use

In many RF systems, noise figure is known as a key parameter for characterizing a receiver and its ability to detect weak incoming signals combined with self-generated noise. The presence of these signals are typically low level, so adding a reliable preamplifier will greatly increase the sensitivity of your measurement system.

The Keysight Technologies, Inc. U7227/8A/C/F USB preamplifiers are designed to increase signal analyzer sensitivity for measuring low-level signals by reducing instrument noise figure. Reduced instrument noise figure also reduces noise figure measurement uncertainty in most cases. Powered on a USB platform, compact and portable, the USB preamplifiers eliminates the need for an external power supply and is ideal for either benchtop measurements or on remote front end applications.

When connected to the Keysight X-Series signal analyzers, the USB preamplifiers can automatically configure the signal analyzer to detect the specific preamplifier connected. The preamplifier will then download the embedded calibration data such as gain, noise figure and S-parameters. The calibration data provides accurate correction data and more repeatable results for each measurement made.

The combined solution of the Keysight U7227/8A/C/F USB preamplifiers and the X-Series signal analyzers delivers the most efficient test setup, highest accuracy and lowest measurement uncertainty for noise figure measurement applications up to 50 GHz.

Improve Noise Figure Measurements

Adding a preamplifier to a noise figure measurement system can significantly reduce the overall system noise figure. The total system noise is dominated by the noise figure of the preamplifier.

Where F and G are noise figure and preamplifier gain, both in linear terms.

For systems with a single preamplifier, where the gain of the preamplifier is greater than or equal to the spectrum analyzer noise figure, the system noise figure is approximately equal to the noise figure of the preamplifier.

Increase Sensitivity and Speed

Measurement system sensitivity for measuring low-level signals can be improved by adding a preamplifier. Alternatively, boosting the sensitivity of your signal or spectrum analyzer with the U7227/8A/C/F USB preamplifiers can provide a means for achieving a faster measurement speed. An analyzer with low noise figure allows you to use a wider resolution bandwidth, yet achieve the same sensitivity. Sweep times can improve one hundred times for each decade increase in bandwidth. The U7227/8A/C/F USB preamplifiers have gain and noise figure characteristics that optimize dynamic range and sensitivity.

Low Noise Amplifier Measurements

Figure 2 above shows the typical setup with a Keysight X-Series signal analyzer for noise figure measurements on a low noise amplifier (LNA) device using the Y-factor measurement technique. The method begins with the calibration setup shown in Figure 1; connecting the USB preamplifier and noise source to the X-Series signal analyzer, setting a start and stop frequency, then calibrate the system through the noise figure measurement application on the signal analyzer. The next step is to insert the LNA and observe the gain and noise figure for the measurement as shown in Figure 2. The built-in uncertainty calculator for the signal analyzer will perform the calculation work for you by importing uncertainties from the specification guide, calibration data from the SNS (noise source), and the gain, noise figure, and match terms of the USB preamplifiers. The uncertainty calculator will also import the LNA noise figure and gain terms from the previous measurement.