I made some analyses regarding the SiLab Radio IC SI4032 and especially the integrated Class E-Power Amplifier (Port 1) and the Output Matching Circuit to the Antenna (Port 2)
What are the values of the inductors in the Radio RF Path?
I measure all inductor in the circuit:
L406, L402 = 10nH; L407 = 20nH; L403 = 27nH; L404 = 43nH; L405 = 24nH; L401 = 12nH; L408 = 270nH
What kind of Diode is D401?
D401 is a bidirectional TVS Diode with Ubreak of 10V and a Junction Capacitance of 5pF what is a significantly impact in the Matching Network.
The Insertion Loss of 0,5dB an Return Loss of -15dB / -12,5dB at 401MHz is a good result.
4.1. Conclusion:
In case of usage in the 70cm Amateur Radio Band and programming the Radio Frequency to 433MHz a Insertion Loss of -1,9dB and a Return Loss of -7dB may be acceptable with out modification. Nevertheless additional measurements of Output Power and Spurious Emission should be performed later.
What are values of the inductor in the GPS RF Path?
I made some analyses regarding the SiLab Radio IC SI4032 and especially the integrated Class E-Power Amplifier (Port 1) and the Output Matching Circuit to the Antenna (Port 2)
I measure all inductor in the circuit: L406, L402 = 10nH; L407 = 20nH; L403 = 27nH; L404 = 43nH; L405 = 24nH; L401 = 12nH; L408 = 270nH
D401 is a bidirectional TVS Diode with Ubreak of 10V and a Junction Capacitance of 5pF what is a significantly impact in the Matching Network.
Simulation Schematic:
Simulation Output: (S11, S21) (S22, S12) (Marker 401MHz)
The Insertion Loss of 0,5dB an Return Loss of -15dB / -12,5dB at 401MHz is a good result.
4.1. Conclusion:
In case of usage in the 70cm Amateur Radio Band and programming the Radio Frequency to 433MHz a Insertion Loss of -1,9dB and a Return Loss of -7dB may be acceptable with out modification. Nevertheless additional measurements of Output Power and Spurious Emission should be performed later.
GPS RF-Path: L304 = 27nH; L302 = 10nH; L303 = 13nH; L301 = 6,8nH