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I am searching for any type of guides for pcb design for SDR (software defined radio) application without luck. I am planning to design pcb board with Zynq-7000 and AD9364 onboard. Any recommendation and useful links? Thanks.

user3583807
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  • Not exactly what you asked but some info here: [Board-Level Design Challenges for Military Software Radios](http://www.pentek.com/tutorials/24_1/MilSftRadio.cfm) – Antonio Mar 25 '16 at 11:27

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If you intend to use this transceiver with high data rates then the interface between this and the Zynq should follow high speed routing guidelines for power and ground.

I note that there is some guidance in the datasheet on power and ground, but it is not extensive.

If you intend to have an external antenna, that will make things a bit simpler, although there is guidance for PCB mounted devices.

There really is no one size fits all guidance with RF and high speed, although some fundamentals are usually followed; note that power and ground plane planning is of the highest importance in this sort of scenario, as is determining proper signal grouping and separation.

More information on the specifics of your application would be helpful for more detailed guidance.

[Update]

The PCB you are attempting to imitate is apparently this one:

USRP physical layout

I can identify the zones with one exception; I have a suspicion that is the TCXO.

Here is a picture of the zones guarded, as far as I can see:

Logical guard zones

The large grounds serve to keep each section clean without interference from other parts of the PCB and are clearly stitched to internal and backside grounds.

The width of this guard ring appears to be about 2mm (the AD9364 is in a 10mm x 10mm package which I used as a reference). That is normally quite sufficient, provided all planes for ground are tied to the guard ring track.

Note that without knowing the stackup, I cannot be more precise as to just how this was implemented, but it is common to see such guarded areas in RF equipment.

The techniques used here are fairly standard in the high speed and RF community as the issues each faces is roughly the same; dealing with high frequency RF energy.

There are many excellent application notes avaliable, such as this one. I also highly recommend Dr. Howard Johnson's articles. I strongly recommend reading some of these, as you will definitely struggle otherwise.

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Peter Smith
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  • I need design USRP B200mini-i like device with xc7z020-1clg400 instead of Spartan chip (ettus.com/product/details/USRP-B200mini-i). It is external antenna will be used and USB-2.0 or Ethernet (PS sided) connection to PC. So I am searching some explanation about wide gnd traces that divide USRP-B200mini-i's pcb into the several parts. What is their purpose and how to design them? – user3583807 Mar 25 '16 at 16:22
  • Does keeping sections clean is reached with using shields that are must be attached for pcb, specifically for that GND traces? – user3583807 Mar 25 '16 at 16:57
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You can use the tool "Polar" to calculate the traces of your PCB to get the right impedance.

Dave Tweed
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josejos41
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