Several Base Station Remote Radio Heads (RRH) and Antenna Integrated Radios (AIR)
Determine if the Power Amplifier Module (PAM) uses Doherty combiner architecture and simulate its performance under dynamic loads.
- The product teardown was undertaken and RF Amplifier Module circuit board was isolated.
- Performed a detailed circuit extraction and analysis to determine the microwave integrated circuit (MIC) topology of the PA module:
- Main amplifier input and output matching networks
- Peaking amplifier input and output matching networks
- Doherty combiner geometry
- The dielectric material used were determined by measurement
- Based on the above circuit extraction a simulation was performed using ADS (2-D numerical analysis, Momentum) to generate the S parameters.
- Harmonic balance technique was used for non-linear simulation of the PA circuit topology.
- Simulation results were analyzed.
- The main and the peaking amplifiers were identified and their functions deduced.
- The circuit was successfully mapped to a variant of Doherty architecture.
- Load modulation was proven based on the simulation results.