How to Use a 2400 MHz Yagi Antenna
These 2400 MHz PCB Yagi antennas are used for 2.4 GHz UHF wi-fi, 2.4 GHz video, beacons, rovers, wireless systems and RFID applications. How else are 2.4 GHz yagis used?
2.4 GHz Wi-Fi Antennas
2.4 GHz antennas fall under the IEEE 802.11 wireless standard by the IEEE. Wi-fi antennas in the 2400-2450 MHz range use the ISM band.
One of the downsides of this frequency range is that equipment on this frequency sometimes suffers from interference from Bluetooth devices, cordless telephones and microwave ovens. This interference is offset in some cases by using direct sequence spread spectrum or DSSS or orthogonal frequency division multiplexing or OFDM.
Other antennas have shifted to the 5 GHz band, since it has more non-overlapping channels. However, shifting frequency ranges can impact performance. While the 5 GHz network could theoretically carry more data than the 2400 MHz network, in practical applications, it doesn’t make much of a difference. One area where 5 GHz and 2.4 GHz antennas dramatically improve wi-fi performance is when one antenna of each frequency range is used. Then data transfer rates are doubled, since both a 2.4 GHz wi-fi antenna and 5 GHz wifi antenna can be used in tandem in the same space without interfering with each other.
On a related note, Google Project Loon, using high altitude balloons to fill in the internet's regional gaps, uses the 2400-2450 MHz frequency range.
2400 GHz Video Antennas
One use of the 2400-2450 MHz PCB yagi is for audio visual transmitters and receivers. These antennas are frequently used for audio-visual signals like wireless closed circuit televisions (CCTV), charge coupled devices (CCD) used in security systems, wireless video cameras, wireless VCR recording and DVD players.
2.4 GHz video signals tend to be very clear because of the high bandwidth transmissions. When these antennas are used for audio-visual transmissions, they have a range of up to four kilometers in open areas.
2.4 GHz Beacons
Part of the 2.4 GHz frequency band is dedicated to amateur radio. A 2400-2450 MHz PCB yagi is perfectly suited to this application. It can be assembled by soldering the coax shield to the reflector and center conductor using semi-rigid coax, RG142 teflon coax or 50 ohm coax. These antennas have an average gain of dBi when used for ham radio applications.
The 2.3 GHz to 2.4 GHz frequency ranges are some of the most under-utilized ham radio bands.
These 2400 to 2450 MHz antennas can be used for 2300-2400 MHz ham radio communications if you have an amateur radio license in the United States that lets you operate on the 13 cm ham band.
Performance of these antennas is affected by plastic housing, shifting their frequency range up when encased in plastic.
2400 MHz Wireless Systems
2.4 GHz antennas are regularly used for wireless internet connections, especially for wide area networks or WAN.
The 2.4 GHz radio systems are also used for remote controlled devices like toy helicopters and remote controlled cars.
In one novel application, David Rowlands, David Thiel and James Kirkup used waist mounted beacons in the 2.4 GHz to track the locations of basketball players in real time. This allowed coaches to identify the players with the ball and the location of other players to that key individual, as well as recorded positional information over time so that the history of plays could be reviewed later to improve player performance.
2400-2450 MHz RFID Antennas
Active RFID applications often operate in the 2.4 GHz ISM band. For RFID transmissions, the permitted operating frequency band is 2400-2450 MHz.
RFID software is usually proprietary, but you can use applications like the Open Source OpenBeacon project. OpenBeacon tracker for RFID even has an open hardware system, a non-proprietary RFID system design that anyone is free to build.
Use of 2.4 GHz antennas may require an amateur radio license or ham radio license in some countries. Due to the number of wireless communications that use this frequency, some nations even ban private antennas in this frequency range without a license. It is the responsibility of the user to verify that this antenna and transmissions in this frequency range are allowed in your country.