Is double biquad or biquad antenna can work on Dualband,,,? If you can, how to make it happen, starting from design to a count, who became Dualband,,, thank you.
e2d, what frequencies are you trying to use? Is this a WiFi antenna? Cellular?
Most antenna designs will work at most frequencies, though some are impractically large at low frequencies. We need to know more about what you're trying to do if you want us to help you.