ANT-2.4-WRT-xxx Data Sheet by Product Description 19.0 mm The WRT Series antenna is ideally suited for (0.75 ) applications such as wireless vending, security, Adhesive Ring Remove protective plastic traffic, or power equipment which require an 11.0 mm before installation (0.43 ) unobtrusive, tamper-resistant antenna solution. SMA or or U.FL The tiny 19 x 11 mm radome installs through a RP-SMA 6.0 mm (0.24 ) small hole on the product and is anchored by a M11x1.0 mm threaded base. An adhesive foam compression ring Thread i-PEX silouette is used to resist the elements. The -wave antenna shown in shadow also features an integral counterpoise, which 32.5 mm eliminates the need for a proximity ground plane. (1.28 ) Counterpoise The antenna is suited for mounting in applications 5.26 mm where the counterpoise will not be shielded (0.207 ) from the antenna (non-conductive or open metal enclosures) installation where the counterpoise is within a shielded enclosure will affect the antenna performance. The antennas coax feed is available with SMA, RP-SMA, or a U.FL / MHF compatible connector. U.FL and I-PEX MHF connector Cable Length 216.0 mm standards are compatible with each other. Alternate (8.50 ) coax lengths, connectors and custom colors are available for volume OEM customers. Ordering Information ANT-2.4-WRT-RPS (with RP-SMA connector) Features ANT-2.4-WRT-SMA (with SMA connector) Low cost ANT-2.4-WRT-UFL (with U.FL / MHF compatible connector) Unobtrusive Tamper resistant Integral counterpoise Indoor / outdoor Adhesive or permanent mount Electrical Specifications Center Frequency: 2.45GHz Recom. Freq. Range: 2.42.5GHz Wavelength: -wave VSWR: 1.9 typical at center Peak Gain: 3.5dBi Impedance: 50-ohms Connector: RP-SMA, SMA or U.FL / MHF Cable: RG-174, RP-SMA & SMA 1.32 mm U.FL Oper. Temp. Range: 40C to +90C Max. Recom. Torque: 4.0 kgf-cm Electrical specifications and plots measured on 10.16 cm x 10.16 cm (4.00 x 4.00) reference ground plane 1 Revised 12/9/13VSWR Graph VSWR 1.543 Reflected Power 3:1 25% 2:1 11% 1:1 0% 2350MHz 2450MHz 2550MHz What is VSWR The Voltage Standing Wave Ratio (VSWR) is a measurement of how well an antenna is matched to a source impedance, typically 50-ohms. It is calculated by measuring the voltage wave that is headed toward the load versus the voltage wave that is reflected back from the load. A perfect match will have a VSWR of 1:1. The higher the first number, the worse the match, and the more inefficient the system. Since a perfect match cannot ever be obtained, some benchmark for performance needs to be set. In the case of antenna VSWR, this is usually 2:1. At this point, 88.9% of the energy sent to the antenna by the transmitter is radiated into free space and 11.1% is either reflected back into the source or lost as heat on the structure of the antenna. In the other direction, 88.9% of the energy recovered by the antenna is transferred into the receiver. As a side note, since the :1 is always implied, many data sheets will remove it and just display the first number. How to Read a VSWR Graph VSWR is usually displayed graphically versus frequency. The lowest point on the graph is the antennas operational center frequency. In most cases, this will be different than the designed center frequency due to fabrication tolerances. The VSWR at that point denotes how close to 50-ohms the antenna gets. Linx specifies the recommended bandwidth as the range where the typical antenna VSWR is less than 2:1. Data Sheet ANT-2.4-WRT-xxx 2 by