Over-the-Air Noise Temperature Measurement

Noise temperature is one of the key performances of RF components, such as the amplifiers in those receivers and transmitters. It is essential to measure the noise temperature accurately; however, the traditional conduction method is no longer suitable for those components with integrated antennas, e.g., antennas in packages (AiPs) or antenna on chip (AoC). This article proposes a solution for noise temperature measurement based on the over-the-air (OTA) method. First, the concept and the problem of noise temperature for those devices integrated with RF components and radiation elements are reviewed, the proposed OTA noise temperature measurement and calibration methods are presented, the measurement systems are set up and at both C-band and millimeter-wave band with different measurement distances under both transmitting and receiving states are demonstrated in detail, and the measured results are compared and discussed which verifies that this proposed method is technically feasible for the OTA noise temperatures with high accuracy.