The farfield measurments can be done for the general antennas, where as there is no general information about measuring the nearfield. eventhough the nearfield does not provide the plane waves. For near field communcation devices like RFID, small size antennas requires this type of measurements. I want to know is there a better way to measure this in a compact way
I also know that we can perform near field analysis using the nearfield probes. but i want to know does the performance is same as the general measurement we carryout for the farfield?
Thank you
The near field and far field are measured by the same way. They are measured either by the magnetic field sensor or electric field sensors. These fields are much higher than the far field so they need to let the sensors working in their linear range far from simulation.
So, they are measured also in anechoic chamber.
Best wishes
The near field and far field are measured by the same way. They are measured either by the magnetic field sensor or electric field sensors. These fields are much higher than the far field so they need to let the sensors working in their linear range far from simulation.
So, they are measured also in anechoic chamber.
Best wishes
Thankyou for your response Dr. Abdelhalim abdelnaby Zekry. But the electric and magnetic field sensors can only determine its respective fields. Is it enough to determine the fields or we have to implement those values into a certain formula to be resulted as dBi (which is the unit of gain in farfield analysis).
Thankyou
Nithyanandham Ganeshwaran,
It is enough to represent the fields in their absolute magnitude. But If you want to get the field level you can use the formula 20 log E/E0 and likewise 20 log H/H0 where E0and H0 are reference electric field and magnetic field at one meter for example.
You can refer them also to the field of an isotropic radiator Ei andHi that would radiate the same power equally at all directions.
You must be aware that near field is different from the far field. The near field comprise the resident field and the propagating field.
The near field represents the energy stored in the inductors and capacitors of the antenna in addition to the propagating field.
Best wishes
Thankyou Dr Abdelhalim abdelnaby Zekry for your answers. I will definitely implement the ideas you have mentioned.
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