RF Test Measurements

Impedance
Most RF equipment will have a specified impedance. Network analyser measurements are undertaken to ensure that the impedance, consisting of both reactive and resistive elements are within specified limits. Measurement results may be provided in Smith Chart or log magnitude formats.

Sensitivity
Sensitivity is the minimum signal strength that a radio will decode and represent the received information at an acceptable quality level. Typically for digital systems sensitivity is specified as a Bit Error Rate (BER) or Symbol Error Rate (SER). For analogue systems it is normally specified as SINAD (Signal Including Noise and Distortion).

Adjacent Channel Rejection
Adjacent Channel Rejection is a measure of how well a receiver operates when an interfering signal is present in the adjacent receive channels.

Occupied bandwidth
Occupied bandwidth integrates the power of the signal, and typically represents the bandwidth occupied by 99% of the signal.

Frequency
Centre frequency and frequency offset measurements, are used to align a transmitter to the desired frequency. Where a design does not provide alignment it is used a metric of transmit quality or performance.

Spurious Emissions
The spurious emissions test identifies and determines the power level of unintentionally generated signals in certain frequency bands.

Adjacent Channel Power
Adjacent channel power is the power that leaks into adjacent transmit channels.

Channel Power
The power spectral density of a signal in a specified channel bandwidth.

Harmonic Distortion
Harmonic distortion is a measure of the relative amplitude of a specified number of harmonics.

IP3 (TOI)
Third-order intercept point (IP3 or TOI) is the point at which the linear extrapolation (as a function of input power) of linear output power and third-order distortion power level meet.

Vector Signal Analysis
Analysis of modulated signal quality. Measurement data can be recorded as eye-diagrams, constellation diagrams or text based error vector magnitudes.

Noise Figure
Noise Figure is defined as the ratio of signal to noise ratio at the output to that at the input.