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Design >> RF Design >> RF limiter for sub 0dBm power
https://designers-guide.org/forum/YaBB.pl?num=1475651661

Message started by Hammad33 on Oct 5^th, 2016, 12:14am

Title: RF limiter for sub 0dBm power
Post by Hammad33 on Oct 5^th, 2016, 12:14am

Hello, I'm currently working on a receiver in which I would like to limit the RF power at input to -10dBm ~ -15dBm. All of the pin diode limiter (including schottky enhanced) schematics that I have seen limit power as low as 0dBm and not below that. I came across a limiter schematic given in Figure 16 of this link.

http://electronics.stackexchange.com/questions/74633/pin-diode-limiter

I was wondering if by using an amplifier before the schottky diode mentioned in Figure 16, can I tune the limit power to below 0dBm?

P.S, I would like to do it with as little active components as possible :)

Title: Re: RF limiter for sub 0dBm power
Post by Ancel on Oct 7^th, 2016, 12:01pm

Depending on the frequency band and permissible NF, have you considered a resistive attenuator followed by an mmic amp. with a feedback control loop as an ALC or manual level control.

Title: Re: RF limiter for sub 0dBm power
Post by Hammad33 on Oct 9^th, 2016, 6:37am

@Ancel, thanks for your reply. I have considered a feedback loop using the detector that I'm using in my AGC but that would cause a delay of around 2 to 3 usecs, that I don't really want.