The N1921A is a wide band power sensor from Keysight Technologies (formerly Agilent Technologies), designed to measure RF and microwave power with a wide frequency range and high accuracy. It’s used in various applications like wireless communications, aerospace, and research labs for power measurement in RF systems.

Key Features of the N1921A Wideband Power Sensor:

1. Wide Frequency Range:
   • The N1921A covers a broad frequency range from 9 kHz to 110 GHz. This makes it suitable for a variety of applications, including low-frequency RF signals and high-frequency microwave measurements.
2. High Dynamic Range:
   • The sensor can measure power across a large dynamic range, typically from 70 dBm to +20 dBm (depending on the configuration). This range makes it versatile for measuring both very low-power and high-power signals.
3. Accuracy:
   • The N1921A provides high measurement accuracy, making it ideal for precise power measurements in test and calibration setups.
   • It uses a thermocouple-based sensing element to provide accurate and stable readings.
4. Compatibility:
   • The N1921A is designed to work with Keysight’s E4418B or other compatible power meters, as well as with X-Series signal analyzers. It can interface through standard USB, LAN, or GPIB communication for remote measurements or integration into automated testing systems.
5. Real-Time Measurement:

The sensor provides real-time power measurements, which is crucial for testing dynamic signals like pulsed RF signals, modulated carriers, and more.

6. Multiple Measurement Formats:

It supports multiple types of power measurements, such as average power, peak power, and pulse power measurements, depending on the application needs.

7. High-Speed Performance:

Designed for quick power readings, the N1921A can handle fast signal fluctuations, making it useful in high-speed, high-precision testing scenarios like communication systems.

8. Temperature Stability:

The sensor is built to operate in a wide range of temperatures, providing consistent performance in various environmental conditions.

Common Applications:

• Aerospace and Defense: Measurement of radar signals, communications systems, and other high-frequency technologies.
• 5G Testing: With the sensor’s wide bandwidth, it’s suitable for testing emerging 5G communications systems operating in higher frequency bands.
• Microwave and RF Research: Used by researchers and engineers to measure the power output of various RF and microwave devices.
• Wireless Communications: Ensures accurate power levels for testing signal strength in wireless systems, including satellite, cellular, and broadcast communication technologies.

Typical Use Cases:

• Power Metering: Often combined with a power meter (e.g., the E4418B) to provide real-time power readings over a wide frequency spectrum.
• Signal Testing: Used for characterizing transmitters and measuring the power of modulated or pulsed RF signals.

Lab Calibration: In laboratories, the N1921A can be used to verify the power of test equipment and calibrate other power sensors.