Abstract: A method allows access to an electronic device disposed in a working space by a user having a remote device is disclosed. An access point transmits an initial signal instructing the remote device to respond after a delay period, which responds upon the expiration of the delay period. A distance of the remote device is determined based upon a period interval from the transmission of the initial signal to the detection of a response signal and the known positions of the access point and the electronic device. Alternatively, a fixed device transmits locating signals detected by three access points, which measure a time differential. The position of the remote device is determined based upon a time of arrival, the location of each of the access points, and the time differential. The electronic device is enabled when the remote device is within the predetermined distance range.

Abstract: The subject invention provides a method of allowing access to an electronic device (218) disposed in a working space (14) by a user (16) having a remote device (212). An initial signal is transmitted from an access point (20) instructing the remote device (212) to respond after a delay period. The remote device (212) responds upon the expiration of the delay period. The access point (20) measures a period interval from the transmission of the initial signal to the detection of a response signal. A distance of the remote device (212) is determined based upon the period interval and the known positions of the access point (20) and the electronic device (218). In another embodiment, a fixed device (256) transmits locating signals detected by three access points (220, 221, 223) and the access points (220, 221, 223) measure a time differential. The position of the remote device (212) is determined based upon a time of arrival, the location of each of the access points (220, 221, 223), and the time differential.

Abstract: The subject invention provides a method to determine the proximity of a user (11) having a first electronic device (12) to a second electronic device (14) for allowing the user (11) access to the second electronic device (14). The method includes the steps of transmuting data (44) in a plurality of signals at different frequencies to establish communication between the first electronic device (12) and the second electronic device (14). The method further includes detecting the plurality of signals at the different frequencies with the first electronic device (12). The method is characterized by determining an overall signal strength from the predetermined number of measured signals strengths and comparing the overall signals strength to a predetermined threshold for enabling the second electronic device (14) in response to the overall signal strength being above the predetermined threshold.

Abstract: A method of synchronizing wireless communication between computer (16) having a transmitter (24) and a peripheral device (50) having an amplitude modulated (AM) receiver (54) and at least one frequency modulated (FM) receiver (56) which communicates via radio frequency signals. The computer (16) partitions the data (28) into a plurality of data blocks (30), spreads the data blocks (30) over a plurality of frequency channels (38) within a predetermined range (70), and selects one of the channels (32) for transmitting the signal (40). The resulting signal (40) has increased and decreased frequency corresponding to the data block (30). The peripheral device (50) detects the signal (40) as being present and begins measuring a time period (64) with the AM receiver (54). The method is characterized by scanning the plurality of frequency channels (38) with the FM receiver (56) during the measured time period (64).

Abstract: A security apparatus and a method for determining the distance between a computer (72) and a token (70) carried by a user (52) for allowing the user (52) to access the computer (72). The computer (72) is connected to a first transceiver (16) having at least one antenna for emitting and detecting a radio frequency (RF) signal, and to a microphone (76) for detecting an audio signal (24). The computer (72) is also connected to a counter (26) for measuring a time interval (28) between a transmitted RF signal (20) and audio signal (24) from the token (70). The token (70) is connected to a second transceiver (30) having at least one antenna for emitting and detecting a RF signal (20) and a loudspeaker (74) for emitting an audio signal (24).

Abstract: The method of the subject invention includes the steps of transmitting a radio frequency (RF) signal from a first electronic device (18) and detecting the RF signal (48) from the first electronic device (18) with an access point (20). The method also includes transmitting a RF signal (50) from a second electronic device (12) and detecting the RF signal (50) from the second electronic device (12) with the same access point (20). The method is characterized by enabling the first electronic device (18) to allow the user (16) having the second electronic device (12) to access the network (13) and the first electronic device (18) in response to the access point (20) detecting the RF signals (48, 50) from both the first (18) and the second electronic devices (12).

Abstract: A security apparatus and a method for determining the distance between a computer (72) and a token (70) carried by a user (52) for allowing the user (52) to access the computer (72). The computer (72) is connected to a first transeiver (16) having at least one antenna for emitting and detecting a radio frequency (RF) signal, and to a microphone (76) for detecting an audio signal (24). The computer (72) is also connected to a counter (26) for measuring a time interval (28) between a transmitted RF signal (20) and audio signal (24) from the token (70). The token (70) is connected to a second transceiver (30) having at least one antenna for emitting and detecting a RF signal (20) and a loudspeaker (74) for emitting an audio signal (24).

Abstract: The subject invention provides a method to determine the proximity of a user (11) having a first electronic device (12) to a second electronic device (14) for allowing the user (11) access to the second electronic device (14). The method includes the steps of transmuting data (44) in a plurality of signals at different frequencies to establish communication between the first electronic device (12) and the second electronic device (14). The method further includes detecting the plurality of signals at the different frequencies with the first electronic device (12). The method is characterized by determining an overall signal strength from the predetermined number of measured signals strengths and comparing the overall signals strength to a predetermine threshold for enabling the second electronic device (14) in response to the overall signal been above the predetermine threshold.

Abstract: A method of detecting a signal (10, 10′) between a token (12) and an electronic device (14) for authorizing a user (16) to access the electronic device (14). The method comprises the steps of emitting a signal (10, 10′) containing data, detecting the signal (10, 10′) with a plurality of antennas (18, 18′), and measuring the strength of the signal (10, 10′) detected at each of the antennas (18, 18′). If the maximum signal strength detected by any of the antennas (18, 18′) is above an operational threshold, the electronic device (14) will be enabled. If the signal (10, 10′) is above the operational threshold, the signal (10, 10′) is compared to a user code database for authorizing the user (16) to access the electronic device (14). The operational threshold may be lowered to account for any signal variances that may occur after the user (16) has been authorized to access or when accessing the electronic device (14).