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Well, this antenna works for sure, but needs little tuning by shortening the directors. I connected 50cm of ALSR-195 cable directly to feed points through hole in reflector. Results from calibrated NanoVNA-F v2 (I noticed that when the antenna is horizontal to the ground its gain increases above 30 dB):

I want to build TV DVB-T antenna for 470-670 MHz band, so firstly I was think about double biquad because I have one biquad and it works. Signal strength is 100% at 14 km distance from 50 kW transmitter, but sometimes it drops and the picture is choppy. I simulated a dual biquad, but the results do not encourage to build this antenna. Specially I mean VSWR and real impedance, which are quite high and depend heavily on frequency. So I'm look only at gain reported by farfield monitors. Is this a good approach to simulating such antennas in CST Studio? Will my design TV-dbq.cst (I have only 275x685 mm reflector) work good as TV DVB-T receiving antenna in 470-670 MHz band?

Last version of my wifi bowtie antenna. Again, I increased the dimensions of the reflector to 200x260mm. This improved the parameters of the simulated antenna, presented in the images below. The prototype of this design is almost ready, I'm just waiting for a cable and connectors from China. Prepare for a big test with my wifi adapter and also I will measure the real parameters with NanoVNA-F v2. I hope this antenna will work Project file (CST Studio 2020): BowTie v3.cst

I changed the reflector size to 175x235 mm and parameters of my bowtie antenna for 2.4 GHz were improved: dBi (2.442 GHz) = 15.76, S-Parameter [magnitude dB] = -36.50, VSWR = 1.03, Impedance = 48.57. Here is project file (CST Studio 2020): BowTie v2.cst Soon I will try to build and test this antenna with my USB wifi dongle adapter.

So, I have designed my version of this antenna for 2.4 GHz (CST Studio 2020). BowTie.cst

I added reflector (170x244mm, Steel-1008, 1mm thickness) with space between it and vibrators h=8mm. Now it is quite good antenna for 2.3 GHz I must change dimensions of elements and maybe it will work for Wifi 2.4 GHz. The impedance chart is interesting; by changing "h" space between reflector and vibrators, impedance was drop to 53 Ohms. So does antenna not require any impedance matching now and can be connected directly with a coaxial cable?

After change frequency range and farfields to 1.942-2.942 GHz warning message is not showing.

I already had this frequency set from 2 to 3 GHz, I also tried change it from 0-5 GHz, but warning message is still displayed. Well, it's my first design. How to automatic position of port between these cylindrical elements?

In my design of this BowTie antenna. Maybe you can correct it, add a reflector and simulate the results BowTie.cst

When simulating my antenna in CST Studio 2019 I get these messages: 1. "Defined reference frequency for open boundary condition (2.442 GHz) is larger than the lowest relevant system frequency (monitor at 2 GHz). Please check open boundary settings to ensure accurate monitor results for the lowest frequency of interest." 2. "1037 mesh edges are represented in staircase mode and have been filled with PEC. 3533 mesh edges are partially filled with PEC." What should I do?