Title:
パルス整形およびプログラマブル周波数シンセサイザを備えたSAWデバイスを利用するRFモデム
Document Type and Number:
Japanese Patent JP2009540762
Kind Code:
A
Abstract:
A bidirectional direct sequence spread spectrum half-duplex RF modem. that can be applied to transmit and receive numerous types of analog and digital pulse modulation. The modem incorporates a SAW based correlator for performing the spreading and de-spreading functions in the transmitter and receiver. A programmable frequency synthesizer provides the frequency source for various signals in the modem including the local oscillator (LO), IF interrogating pulse and clock signals. An upconverter/downconverter provides frequency translation to the desired frequency band. Pulse gating and interrogating pulse shaping are employed to reduce the spectral side bands of the transmitted spread pulse. The RF modem operates as an analog or digital pulse transmitter and receiver. It is adapted to be generic and is versatile enough to be used in many different types of data communication systems, such as OOK, PWM and PPM. The RF modem can be used as the physical (PHY) layer in a layered communication system such as the ISO OSI communication stack. In an alternative embodiment, the transmission bit rate is increased by using a plurality of correlators wherein each is configured with a unique function (i.e., code) that is orthogonal to the other functions.
Inventors:
Ben-Bassat, David
Application Number:
JP2009515548A
Publication Date:
November 19, 2009
Filing Date:
May 11, 2007
Export Citation:
Assignee:
Vishay Intertechnology, Inc.
International Classes:
H03K5/00; H03K7/02; H03K7/04; H03K7/08; H03K23/66; H04B1/54; H04B1/707
Domestic Patent References:
| JPH1132111A | 1999-02-02 | |||
| JP2002344348A | 2002-11-29 | |||
| JP2003511959A | 2003-03-25 | |||
| JP2004080624A | 2004-03-11 | |||
| JP2002290231A | 2002-10-04 | |||
| JP2000224037A | 2000-08-11 | |||
| JP2001202153A | 2001-07-27 |
Attorney, Agent or Firm:
Nobuaki Kazehaya
Noriko Asano
Noriko Asano