Re: [Discuss-gnuradio] Analog Devices RF RX/TX subsystems for Spartan-3AN FPGA

[Jeffrey Lambert]

On 6/18/2010 12:43 AM, Elvis Dowson wrote:
> Would it make sense to model and simulate using Matlab/Simulink, for 
> the amplifiers, mixers and other components using their datasheets?
Simulation is helpful, but it cannot replace the design process.  The 
parameters you will need can potentially come from datasheets, but 
manufacturers don't often provide enough information in the datasheet or 
take much care in producing the given results.  For receiver design, 
s-parameters are sufficient except in the case of amplifier or component 
design.  This type of data is usually separate from the datasheet if 
it's available at all.  I would recommend characterizing all devices 
yourself with equipment that has been properly and carefully calibrated.
> Matlab/Simulink has a VHDL code generator for Xilinx, so I am 
> wondering if I could use it initially to model the behaviour or the RF 
> part, and then later on, use it to realize the baseband processor?
I don't know about Matlab's capabilities, but the approach seems 
correct.  What do you mean by "baseband processor"?
> What other tools would I need to complete the process, so that I can 
> model, simulate, and develop the schematics and PCB layout for the RF 
> front end? e.g Is Altium Designer better, and does it have all the 
> required RF modeling and simulation capabilities or should I use pspice?
Access to PCB fabrication equipment is helpful, but not required.  Open 
source layout tools are available if cost is an issue, but I am not 
familiar with any open source RF tools.  SPICE is not adequate for high 
frequency work; you will need something like Agilent's Advanced Design 
System.

With any hardware design, simulations are good to verify circuit 
operation and measurement results, but sometimes there is black magic 
involved that can only come from hands on experience.  There is a lot of 
theory and background that goes into RF design and what you are asking 
is not as simple as it might seem.

~Jeff

--
~Jeffrey Lambert,  K1VZX