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Below are all of the forum threads, including all
the responses to the original posts.
Post subject: Receiver Antenna in SPICE Posted: Wed Apr 15,
2009 1:13 pm
Joined: Wed Apr 15, 2009 12:58 pm
I need to include a receiver antenna in SPICE simulation.
Should I model it as a current source or voltage source? Does this depend
on the type of antenna (whether it's a dipole, loop, etc) that I use?
Please help. Thx.
Post subject: Re:
Receiver Antenna in SPICEPosted: Wed Apr 15, 2009 4:19 pm
Joined: Wed Apr 08, 2009 7:53 am
I think you
can manage to use any of those sources as long as it has the correct
internal characteristic impedance of your system.
Re: Receiver Antenna in SPICEPosted: Wed Apr 15, 2009 4:40 pm
Joined: Mon Jun 27, 2005 2:02 pm
Antenna should be simulated as voltage
source. The type of antenna does not matter for the SPICE simulation.
Post subject: Re: Receiver Antenna in SPICEPosted:
Wed Apr 15, 2009 8:11 pm
Joined: Wed Apr 15,
2009 12:58 pm
Thanks for all the replies. Could you
give a reason why it should be modeled as a voltage source instead of
a current source?
My original thought was if it were a loop antenna,
it should be modeled as a voltage source because the signal is generated
on the received antenna thru Faraday's law of induction, i.e. emf=change
of flux. However if it were a dipole, it should be modeled as a current
source because signal is generated due to lenz's law?(I'm not confident
Post subject: Re: Receiver
Antenna in SPICEPosted: Fri Apr 17, 2009 4:05 pm
Joined: Mon Jun 27, 2005 2:02 pm
Why a voltage source? good question.
1. In all of
the RF text books I have encountered Antenna is modeld as voltage source,
transmitter is modeled as voltage source with Thevenin resistnce etc
(On the other hand it also could have been modeled as a current source...).
So it is a matter of industry convntion, also the case for: VSWR, S-parameters
2. If you want to add a noise source to the simulation
(Which is very common in simulatin an Antenna circuit) you will also
have to model it through a voltage source and its associated noise resistance
- Johnson noise model. In this case it is easier to combine the signal
voltage with the noise voltage rather than a current signal with noise
Post subject: Re: Receiver Antenna in
SPICEPosted: Sat Apr 18, 2009 10:35 am
Wed Apr 15, 2009 12:58 pm
I am hoping to know the physical
reason why normally reception antenna is modeled as a voltage source.
Whether it's a voltage source or current sources matters in my simulation,
for example, in transient simulation, if voltage source is used, when
the voltage source reaches, let's say, 1mV and the capacitive load is
already charged up to 1mV, current will no longer flow because there's
no voltage difference. However, when current source is used, current
will flow to the capacitive load no matter what.