Wireless communication system using surface acoustic wave (SAW) single-phase unidirectional transducer (SPUDT) techniques
US6462698B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 2001 |
| Grant date | Oct 8, 2002 |
| Priority date | — |
| Expiry date | May 24, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H9/14505
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
SAW devices such as interdigital transducers (IDTs) have been widely used in RADAR applications and as filters. An IDT produces a SAW when excited by a single electrical pulse and can be fabricated to embody a code, which code provides for a passive autocorrelation of a SAW input to the IDT and thereby lends itself to further application as a signal generator in a communication device. However, conventional SAW expanders and compressors typically have insertion losses greater than 20 dB, which can have a profound effect on an RF link budget in a communication system. Insertion losses are drastically reduced by using a single phase unidirectional transducer (SPUDT-type) instead of a conventional IDT as a SAW expander/compressor. A SPUDT-type reflects SAW components which are lost in conventional IDT designs so that a stronger SAW is directed toward a transmission element. In a receiver, a SPUDT-type directs a stronger SAW toward a compressor IDT. A communication system based on SPUDT-type techniques would be low-cost, low-power, small and simple alternative to known short range communications schemes, including for example the BLUETOOTH™ solution. Operation of a SAW system at …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.