초록 ▼

A signal-of-opportunity location device (SOLD) that may be situated in a complex radio propagation environment with multiple RF signal obstructions receives RF signals from a distant transmitter. The RF signals from the distant transmitter interact with obstructions in the propagation environment lo

A signal-of-opportunity location device (SOLD) that may be situated in a complex radio propagation environment with multiple RF signal obstructions receives RF signals from a distant transmitter. The RF signals from the distant transmitter interact with obstructions in the propagation environment local to the SOLD. The local obstructions perturb the RF signals causing the RF signals to exhibit near field behavior in the complex radio propagation environment. The SOLD receives the locally perturbed signals. The SOLD detects signal characteristics of RF signal components of the received signals and compares these signal characteristics with reference data in a reference data store to determine the current location of the SOLD.

대표청구항 ▼

What is claimed is: 1. A method of determining location, comprising:receiving, by a receiver, a radio frequency (RF) signal-of-opportunity that exhibits a signal component at the receiver, the RF signal-of-opportunity being perturbed by a perturber within the propagation environment of the receiver,

What is claimed is: 1. A method of determining location, comprising:receiving, by a receiver, a radio frequency (RF) signal-of-opportunity that exhibits a signal component at the receiver, the RF signal-of-opportunity being perturbed by a perturber within the propagation environment of the receiver, the receiver being configured to receive the RF signal-of-opportunity within near field range of the perturber;detecting, by the receiver, a signal characteristic of the signal component to provide signal characteristic information; andcomparing the signal characteristic information with reference data to determine the current location of the receiver.