ANT-433-MHW-xxx-x Data Sheet by Product Description 5.70 ( ) MHW Series dipole antennas feature a durable, 145.0 unobtrusive housing that sticks permanently with 0.38 9.7 integral adhesive to at, non-conductive surfaces such as windows, drywall, ceiling tiles, plastic, etc. The antennas are well suited to low-power 0.30 devices, but are capable of operation at levels to 7.6 10 watts. The MHW is supplied with either 79 2.19 1.34 2m or 180 4.6m of RG-174 cable and attaches ( ) 55.5 34 via a standard SMA or Part 15 compliant RP-SMA connector. Custom cable lengths and connectors are available for volume OEM customers. 0.22 5.5 0.61 15.5 Features Compact & unobtrusive Adhesive for at surfaces Excellent performance Omni-directional pattern 0.31 Very low VSWR 8.0 Two exible radiating elements Rugged & damage-resistant Standard SMA or Part 15 compliant RP-SMA connector Electrical Speci cations Center frequency: 433MHz Recommended Oper. Freq: 413453MHz Wavelength: -wave VSWR: 1.9 typical at center Peak Gain: 1.2dBi Impedance: 50-ohms Connection: SMA or RP-SMA Cable: 79 or 180 RG-174 coax Ordering Information ANT-433-MHW-RPS-L (RP-SMA connector, 180 4.6m coax) ANT-433-MHW-RPS-S (RP-SMA connector, 79 2m coax) ANT-433-MHW-SMA-L (SMA connector, 180 4.6m coax) ANT-433-MHW-SMA-S (SMA connector, 79 2m coax) 1 Revised 3/22/13VSWR Graph VSWR 1.18 Reflected Power 3:1 25% 2:1 11% 1:1 0% 368MHz 433MHz 498MHz 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 re ected back from the load. A perfect match will have a VSWR of 1:1. The higher the rst number, the worse the match, and the more inef cient 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 re ected 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 rst 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 speci es the recommended bandwidth as the range where the typical antenna VSWR is less than 2:1. Data Sheet ANT-433-MHW-xxx-x 2 by