laygun
Newbie level 2
Hi,
I am driving a half wave rectifier which has an input impedance >>50ohm. I can measure the output voltage and output power.
I would like to measure spectral power transfer/conversion efficiency (Pout/Pin) but I don't know the proper way of measuring the input power to my rectifier. How would you measure it ?
I am considering using a directional coupler but not sure how to do (I am new to RF circuits)
Potential problems:
1-My input signal will be Vpp 2-4V so 10-20dBm range. It will be mostly reflected due to the high input impedance of my rectifier (>10kohm). While the most of the power is reflected can I still accurately measure the small difference (10-100 uW) between the reflected and incident power (from RF power supply or arbitrary waveform generator).
2- Since the diode will conduct for a short part of the period, current will not look like a sine wave and there will be other frequency components. Will this create a problem? (Changing input impedance during a single cycle)
3- As I increase frequency, a capacitor parallel to my diode starts to conduct. So there will be a large instantaneous power, but this will be just charging and discharging the load capacitor and not consuming a lot of power. However my average consumed power will be still small around 10-100 uWatts. (based on my simulations)
4- https://www.minicircuits.com/pdfs/ZDC-10-1+.pdf I found this directional coupler, would you recommend to use this one or do you know better alternative covering my frequency range?
Thanks a lot,
Levent
I am driving a half wave rectifier which has an input impedance >>50ohm. I can measure the output voltage and output power.
I would like to measure spectral power transfer/conversion efficiency (Pout/Pin) but I don't know the proper way of measuring the input power to my rectifier. How would you measure it ?
I am considering using a directional coupler but not sure how to do (I am new to RF circuits)
Potential problems:
1-My input signal will be Vpp 2-4V so 10-20dBm range. It will be mostly reflected due to the high input impedance of my rectifier (>10kohm). While the most of the power is reflected can I still accurately measure the small difference (10-100 uW) between the reflected and incident power (from RF power supply or arbitrary waveform generator).
2- Since the diode will conduct for a short part of the period, current will not look like a sine wave and there will be other frequency components. Will this create a problem? (Changing input impedance during a single cycle)
3- As I increase frequency, a capacitor parallel to my diode starts to conduct. So there will be a large instantaneous power, but this will be just charging and discharging the load capacitor and not consuming a lot of power. However my average consumed power will be still small around 10-100 uWatts. (based on my simulations)
4- https://www.minicircuits.com/pdfs/ZDC-10-1+.pdf I found this directional coupler, would you recommend to use this one or do you know better alternative covering my frequency range?
Thanks a lot,
Levent