in which c is the speed of light = 3*10^8 m/s
Practical Example:
A student has a receiver (MX-RM-5V) and a transmitter (FS1000A) in the 433MHz band. When he/she run the basic code sending "hello world", the distance between them is less than 10 cm. In order to increase the transmission distance, what is the length of the antenna should he/she add?
3*10^8 / 433 * 10^6 = 0.6928 meter
so for half-wavelength antenna: 0.5 * 0.6928 = 0.3464 meter
and for quater-wavelength antenna: 0.25 * 0.6928 = 0.1732 meter or 17.32 cm
That is the reason we want to add the carrier frequency to reduce the length of the antenna.
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| The range is improved significantly after the antennas are inserted |
