Conference Paper

Near-Field Direct Antenna Modulation (NFDAM) transmitter at 2.4GHz

California Inst. of Technol., Pasadena, CA, USA
DOI: 10.1109/APS.2009.5171550 Conference: Antennas and Propagation Society International Symposium, 2009. APSURSI '09. IEEE
Source: IEEE Xplore

ABSTRACT A near-field direct antenna modulation (NFDAM) transmitter at 2.4GHz is demonstrated on a microstrip setting. The transmitter is capable of transmitting information in a direction-dependent fashion by sending the correct signal constellation only in the desired direction while leaving the signal constellation points scrambled in undesired directions. This direction-dependent constellation scrambling nature of the NFDAM systems prevents undesired receivers to correctly demodulate the signal transmitted to a desired receiver at a specific direction.

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    ABSTRACT: A direction dependent communication system based on a simple two element array is described. The system is similar to a conventional phased array but the phase shifters have only 2-bit control. The basic concept of directional antenna modulation is presented and illustrative examples are given. Some of the system characteristics of direction dependent modulation are examined and compared to conventional modulation systems. A simple two element array system configured for direction dependent modulation is introduced and numerical examples are given to illustrate how transmission error rates depend on various system parameters.

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