Abstract: The present disclosure relates to a system and method of cancelling feedback in a vehicle communications system. The system and method may adjust a phase and a polarity of the microphone signal to produce an inverted microphone signal having a shifted phase. A speaker signal may be summed with the inverted microphone signal to cancel out at least a portion of a microphone signal component of the speaker signal.

Abstract: A method of operating a security system includes accessing a database and obtaining a user PIN. A normal keypad is defined in which a plurality of alphanumeric characters are displayed in defined normal positions. A scrambled keypad is also defined including the PIN so that at least some of a plurality of alphanumeric characters are displayed on the scrambled keypad in positions which are different to the positions in which they would be displayed in the defined normal keypad. In addition, for each of the alphanumeric characters of the PIN the alphanumeric character which is normally displayed in the normal keypad in the position in which the alphanumeric characters of the PIN are displayed in the scrambled keypad is determined thereby to arrive at a scrambled PIN Data defining the scrambled keypad is then transmitted to a user over a first communications network.

Abstract: A communications system for a vehicle user is provided. The system comprises a portable receiver which the vehicle user can easily carry on his or her person. The portable receiver is capable of receiving coded transmissions from a vehicle-mounted transmitter which is capable of activating a function in a portable transceiver.

Abstract: A communications system for a vehicle user is provided. The system comprises a portable transceiver which the vehicle user can easily carry on his or her person and a vehicle-mounted transceiver. The portable transceiver is capable of communicating with the vehicle-mounted transceiver. Audio information contained in a transmission from the portable transceiver may be retransmitted by the vehicle-mounted transceiver either to a public address system or a second vehicle-mounted transceiver.

Abstract: A communications system for a vehicle user is provided. The system comprises a portable transceiver which the vehicle user can easily carry on his or her person and a vehicle-mounted transceiver. The portable transceiver is capable of communicating with the vehicle-mounted transceiver. Audio information contained in a transmission from the portable transceiver may be retransmitted by the vehicle-mounted transceiver either to a public address system or a second vehicle-mounted transceiver.

Abstract: A mount for supporting a microphone on a helmet having an outer shell and for use with a transmission cable. The microphone is mounted on a flexible boom carrying leads connected to the microphone. The transmission cable carries electrical conductors. The mount includes an attachment assembly having a surface with a contour which conforms to the outer shell of the helmet. The attachment assembly is provided with a sleeve-like member adapted to receive the flexible boom and a retainer for receiving the transmission cable. Connectors are carried within the attachment assembly for electrically connecting the electrical conductors from the transmission cable to the leads to the microphone. A layer of an adhesive material is carried by the surface of the attachment assembly and is adapted to fasten the attachment assembly to the outer shell of the helmet. The layer of adhesive material permits the fastening of the attachment assembly to the helmet without impairing the structural integrity of the helmet.