EMRFD Message Archive 12231

Message Date From Subject
12231 2016-01-24 22:43:34 mosaicmerc Envelope tracking
Hi All:
I am looking at this IC for UHF AGC purposes.
http://www.analog.com/media/en/technical-documentation/evaluation-documentation/ADL5511.pdf

Since I am new to RF design...I need some clarification on the specs:

0 - 6Ghz range vs 130Mhz Envelope bandwidth.

This confuses me, is the IC capable of  envelope tracking across 0-6Ghz?
Or is it only capable of 130Mhz segments across 0-6GHz, which would make it impractical for measuring power without  multiple bandwidth block switching. eg 0-130Mhz, 130 -260 etc.





12232 2016-01-24 22:54:44 Andy Re: Envelope tracking
   "0 - 6Ghz range vs 130Mhz Envelope bandwidth."

Sounds to me like the carrier frequency can be anywhere from 0-6GHz, but the envelope (modulation) has a 130MHz bandwidth capability.  That is, the detected envelope, or recovered modulation, is subject to a 130MHz upper frequency rolloff.

The IC probably has no tuned circuits so no concept of 130MHz segments, i.e., no RF bandwidth about a center frequency.  The bandwidth limits that exist are maximum frequencies.

Andy


12233 2016-01-25 02:33:21 AncelB Re: Envelope tracking
Ok, then it would be useless as a Peak detector for the carrier as it's
modulation limited.
12236 2016-01-25 21:31:36 Andy Re: Envelope tracking
   "Ok, then it would be useless as a Peak detector for the carrier as it's
    modulation limited."

Well, perhaps only if the modulation components exceed around 100MHz, or if you need it to capture the peaks of isolated pulses narrower than 10ns.  Otherwise, on first glance (and only first glance), it looks like a perfectly usable peak (envelope) detector for most kinds of RF signals you would encounter.

Andy