Back to results
US 2015/0253413 A1Published application
Location system
AssigneeSonitor Technologies AS
InventorsWildred Edwin Booij, Oystein Haug Olsen
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeSonitor Technologies AS
InventorsWildred Edwin Booij, Oystein Haug Olsen
Estimating the term…
Static transmitter stations are used to determine the position of a mobile receiver unit. Each transmitter station transmits an ultrasonic signal including a transmitter-specific phase-shifting signature. The receiver unit receives a signal and identifies a transmitter station by its signature. It uses the received signal and the identity of the source transmitter station to determine the position of the mobile receiver unit. The signature may include two patterns phase-shift-key (PSK)-encoded on respective carrier signals of the same frequency but different phase, with the patterns being offset from each other by a transmitter-specific offset. The signal from the transmitter station may also include a PSK-encoded message.
A system for transmitting information comprising:
The system as claimed in claim I, wherein the transmitter unit is configured to transmit one or more phase reference elements within the message.
A method of transmitting information comprising:
A transmitter unit configured to transmit an ultrasound signal comprising (i) a signature comprising a first pattern which is PSK-encoded on a first carrier and a second pattern which is PSK-encoded on a second carrier, wherein the first and second carriers have the same frequency but wherein the second carrier is out of phase with first carrier, and wherein the second pattern is offset from the first pattern in time by a transmitter-specific offset, and (ii) a PSK-encoded message-bearing portion.
A receiver unit configured to receive from a transmitter unit an ultrasound signal comprising (i) a signature comprising a first pattern which is PSK-encoded on a first carrier and a second pattern which is PSK-encoded on a second carrier, wherein the first and second carriers have the same frequency but wherein the second carrier is out of phase with first carrier, and wherein the second pattern is offset from the first pattern in time by a transmitter-specific offset, and (ii) a PSK-encoded message-bearing portion, the receiver unit comprising a processing system configured to use the first and second patterns in the received signal to characterise a motion-induced phase distortion in the received signal.
Dependencies are inferred from the claim text.