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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