Antenna Range

mussa

Joined Jun 10, 2019
45
how do we calculate length of antenna? For example: If it is 10 meter range we need

Joined Mar 10, 2018
3,884

AlbertHall

Joined Jun 4, 2014
9,270
The dimensions of an antenna are determined by the frequency and impedance matching to the being transmitter or receiver.
The range is determined by the transmitter power and the receiver sensitivity. The antenna can have 'gain' compared to a simple half wave dipole. The gain is achieved by making the antenna directional, that is restricting the angles at which it is effective.

SamR

Joined Mar 19, 2019
1,793
The rough ballpark for a "long wire:" antenna is 1 wavelength optimal. Which is usually too long for many installations so the minimum is usually 1/4 wavelength. The trick though as Albert mentioned is matching the impedance between the RCVR/XMTR and the antenna with a device called an antenna tuner. Some "store-bought" antennas have this incorporated into the antenna. Then there are external tuners and some radios have them built-in. With a proper antenna tuner, I can impedance match an aluminum lawn chair as an antenna but it's effective receive/transmit propagation would be horrible. What frequency are you wanting an antenna for?

mussa

Joined Jun 10, 2019
45
The rough ballpark for a "long wire:" antenna is 1 wavelength optimal. Which is usually too long for many installations so the minimum is usually 1/4 wavelength. The trick though as Albert mentioned is matching the impedance between the RCVR/XMTR and the antenna with a device called an antenna tuner. Some "store-bought" antennas have this incorporated into the antenna. Then there are external tuners and some radios have them built-in. With a proper antenna tuner, I can impedance match an aluminum lawn chair as an antenna but it's effective receive/transmit propagation would be horrible. What frequency are you wanting an antenna for?
i'm using FM tranmitter V2.0 (70-108MHz) and tea5767 fm receiver.

SamR

Joined Mar 19, 2019
1,793
Pretty broadband. 70Mhz ~14 feet to 108Mhz ~9 feet for full wave. What is your XMTR power? Is this a stereo low watt unit? They usually come with a telescoping whip antenna. For high watt, they get up to around 1K$for a directional yagi. What are you using this for, what watt out and what range? eBay has a good used Harris military surplus antenna for ~$40. What happens is for space-saving and portability they start using coiled wire in fiberglass to get the long-wavelength in a compact antenna to save space.

mussa

Joined Jun 10, 2019
45
Pretty broadband. 70Mhz ~14 feet to 108Mhz ~9 feet for full wave. What is your XMTR power? Is this a stereo low watt unit? They usually come with a telescoping whip antenna. For high watt, they get up to around 1K$for a directional yagi. What are you using this for, what watt out and what range? eBay has a good used Harris military surplus antenna for ~$40. What happens is for space-saving and portability they start using coiled wire in fiberglass to get the long-wavelength in a compact antenna to save space.
The transmitter uses 3.3 V it a short range transmitter, Any single wire can act as Antenna.

SamR

Joined Mar 19, 2019
1,793