Single-feed dual-band planar inverted-F antenna with U-shaped slot

The development of small integrated antennas plays a significant role in the progress of rapidly expanding wireless communication applications. This paper describes a novel dual-band planar inverted-F antenna (PIFA) for wireless local area network applications. The proposed PIFA uses single feed only. A novel top-plate geometry, a U-shaped slot, is discussed. An example is given for this novel slot shape for frequency bands of 2.4 and 5.2 GHz. Simulation based upon the method of moments (MoM) is used to model the performance of the antenna. Comparisons with results measured on fabricated antenna structures are provided for simulations validation.     

Radio frequency technology for automated manufacturing and logistics control. Part 2: RFID antenna utilisation in industrial applications

The trend in industrial automation is to move towards fast and real-time identification, further improving the high-level of accuracy that is needed to enable continuous identification and monitoring. The interest in adopting radio frequency identification (RFID) technology for use in automation systems with minimal manual involvement is increasing rapidly. RFID systems are capable of providing real-time object visibility with high accuracy enabling continuous identification and location of all items and thereby providing accurate real-time data management instead of simple snapshots. In this paper, the use of multiple reader antennas is examined against collision and interference avoidance. Also, antenna operation is studied in typical industrial environments containing metallic objects or other conducting surfaces. In addition, this paper reviews different tag antennas and their characteristics for particular item identification cases. These cases include items made of specific materials that obstruct or prevent radio wave propagation by either absorbing or reflecting them. The results given in this paper are fully applicable with practical RFID solutions.     

Radio Frequency Technology for Automated Manufacturing and Logistics Control. Part 1: Passive RFID Systems and the Effects of Antenna Parameters on Operational Distance

Identification plays an important role in automation. In the near future radio frequency identification (RFID) will be an option for mass production automation projects. RFID represents a contactless method for data transfer in object identification. Generally, RFID systems consists of three components: 1. A small electronic data carrying device called a transponder, or a tag that is attached to the item to be identified. 2. A reader or a scanner that communicates with the tag by using radio frequency signals. 3. A host data processing system that contains information on the identified item and distributes information to other remote data processing systems. An RFID system can be considered as a wireless communication system because the scanner communicates with the tag by using electromagnetic waves at radio frequencies. The performance of this communication link can be studied by determining the read range for backscatter RFID systems. The read range, or the distance at which the reader unit notices the tag, depends on many factors. Several parameters, e.g. the frequency used for identification, the gain, the orientation and the polarisation of the reader antenna and the transponder antenna, and the placement of the tag on the object to be identified, will all have an impact on the RFID system read range. In this paper, Part 1, we focus on presenting an overview of different passive RFID systems and the read range of the backscatter RFID system. The function of frequency, antenna gain and polarisation mismatch are analysed and discussed. In Part 2, several manufacturing automation cases of different natures will be presented. These cases contain a selection of requirements for an RFID system and they are analysed using the information presented in this paper.