Debraj Kar

12 Questions 15 Answers 0 Followers

Questions related from Debraj Kar

What will be the impact on Antenna performance to shift the resonant frequency by RLC Matching network?

There is always a possibility to shift the resonance frequency by adding a RLC matching network. I wonder what will be the consequence on antenna performance (axial ratio, gain)? If there is no...

14 September 2020 5,351 3 View

Axial ratio shows different result at different ortogonal setup. What could be the reason ?

Axial ratio seems different when Transmit Antenna stays at 0° and DUT at 0° and 90° Compared to if Transmit Antenna stays at 90° and DUT at 0° and 90°. Similarly, I checked other position, but it...

18 June 2020 5,454 3 View

Why Antenna shows negative gain even though it has very good matching?

I am aware of the fact that electrically small antennas are poor radiators with very small gain and low efficiency. One main cause of this is poor matching. An extremly electrically small antenna...

20 January 2020 5,450 9 View

What is the impact of image current from ground plane on patch antenna? I wonder how it radiates if ground plane is very near to radiator?

As we know, patch antenna is combination of two magnetic dipole. If we place a perfect electrical conductor near a dipole, antenna performance will suffer significantly. Then how a patch antenna...

28 November 2019 7,707 5 View

What will be the cororidinate(theta and phi) to evaluate the axial ratio?

I have designed a circular polarized antenna. But , I am confused with cor-ordinate system. In some angel it shows less than 2 dB axial ratio and some other point it shows more than 10 dB like a...

24 May 2019 2,285 7 View

Why there is a big difference in between realize gain and gain in my design?

I have designed a multiport antenna. Where as, I have 2 dB Gain but realize gain is -6 dB. Point to be noted, S11 is really good. I have -25 dB return loss at my desired frequency.

23 November 2018 6,275 17 View

Why Wilkinson power divider with equal arm shows 180 degree phase shift in between two output ports?

I have designed a simple wilkinson divider with equal arm and 100 ohm resistor. It should be 0 degree phase shift in between out put ports. But It shows 180 degree phase shift in HFSS. Do you have...

19 September 2018 8,730 4 View

How can i check the phase shift in between the two output ports in wilkinson power divider in HFSS?

I would like to check the Phase shift in between two Output ports.

13 September 2018 4,259 14 View

Are there any relation in between Spiral antenna's outer radius and Dielectric constant (different dielectric material) ?

I would like to design an UHF antenna where size limitation (30mm*30mm) will be followed . I was thinking to use high dielectric material so i can minimize the size of spiral antenna. I have tried...

14 August 2018 9,013 1 View

Is it possible to use a Dual polarized antenna instead of CP antenna? For example in RFID: Which antenna can detect most of the tag? CP or DP antenna?

Is it possible to use a Dual polarized antenna instead of CP antenna? For example in RFID: Which antenna can detect most of the tag? Circulsr or dusl polarized antenna?

06 April 2018 7,745 5 View

Why we dont use RFID Tag antenna in RFID Reader?

I am looking for a solution for small RFID Reader antenna in UHF: Iwonder why we dont use the RFID Tag antenna in RFID reader as RFID Tag antenna is very small.

22 March 2018 6,986 8 View

Is it possible to increase the antenna gain by stacking two travelling antenna as like as resonant antenna?

It is a very common practice that stacking the patch antenna and improving the gain. Patch antenna , Di-poles are mostly resonant antenna. But is it possible to follow the same approach for...

01 January 1970 9,109 3 View