Abstract: Delay domain multiplexing, differing from coherence multiplexing of digital data signals, may use orthogonal encoding to reduce cross-channel interference compared to traditional techniques. A plurality of photonic encoders may receive laser pulses from a laser pulse source, converting the pulses into n sets of orthogonal codes, such as Walsh codes, depending on the number of channels to be multiplexed. A passive apparatus may use orthogonal codes, creating them fast enough to function in an optical or photonic environment. The orthogonal codes may subsequently be modulated with n digital data signals before being multiplexed and demultiplexed in a delay domain or coherence multiplexing apparatus. At a receiver, the encoded signals are decoded and the original digital data signals are extracted therefrom.

Abstract: An apparatus for transmitting acoustic signals from a mobile communication device to the ears of a user and from the mouth of a user to the mobile communication device through a fiber optic link. A principal objective of the apparatus is to substantially reduce or eliminate radio frequency radiation exposure to the cranial regions of users of mobile communication devices. One embodiment of the apparatus implements an earphone and microphone system for use with a mobile telephone or other wireless communication device, using no electrical components within the earphone or microphone. The present invention implements a laser-actuated, sound-producing diaphragm as a hearing device. The laser may be contained within a housing connected to a wireless communication device. The laser may be connected to the hearing device by an optical fiber, thus enabling the housing containing the laser to be at a location remote from the hearing device.