Method and apparatus for a low complexity satellite ranging system using Gaussian noise overlay

Claim 1

A ranging system for determining the electromagnetic signal delay to a signal repeater, said system including a transmit-receive station comprising: a source of Gaussian noise; transmitting means coupled to said source of Gaussian noise, for transmitting said Gaussian noise to said repeater, whereby said repeater retransmits said Gaussian noise as retransmitted repeater signals; variable-delay means including a control port, an output port, and an input port coupled to said source of Gaussian noise for receiving said Gaussian noise therefrom, for controllably delaying said Gaussian noise applied to said input port of said variable-delay means under the control of delay control signals applied to said control port of said variable-delay means, to thereby generate delayed Gaussian noise signals at said output port of said variable-delay means; correlation means coupled to said output port of said variable-delay means and also coupled for receiving said retransmitted repeater signals, for correlating said delayed Gaussian noise signals with said retransmitted repeater signal, for thereby generating correlation signals representative of the correlation between said delayed Gaussian noise signals and said retransmitted repeater signals; delay control means coupled to said correlation means and to said control signal port of said variable-delay means, for generating said delay control signals in a manner which tends to maximize said correlation signals; and indication means coupled to one of said delay control means and said variable-delay means, for providing signals indicative of said delay.

Claim 12

A method for determining the electromagnetic signal delay between a repeater and a transmit-receive station, comprising the steps of: at said station, generating Gaussian noise; transmitting signals, including said Gaussian noise, from said station toward said repeater, to thereby generate transmitted signals; at said repeater, receiving said transmitted signals, and generating retransmitted signals including said Gaussian noise, to thereby form retransmitted signals; at said station, controllably delaying said Gaussian noise from said source, to thereby generate delayed Gaussian noise; at said station, correlating said delayed Gaussian noise with said Gaussian noise included in said retransmitted signals, to thereby generate correlation signals representative of the amount of correlation; controlling said step of controllably delaying in response to said correlation signals in a manner which causes said correlation signals to be maximized; and recording at least the amount of delay which results in said maximization of said correlation signals.

Claim 13

A method for determining the electromagnetic signal delay between a repeater and a transmit-receive station, comprising the steps of: at said station, generating Gaussian noise; transmitting signals, including said Gaussian noise, from said station toward said repeater, to thereby generate transmitted signals; at said repeater, receiving said transmitted signals, and generating retransmitted signals including said Gaussian noise, to thereby form retransmitted signals; at said station, controllably delaying said Gaussian noise from said source, to thereby generate delayed Gaussian noise; at said station, correlating said delayed Gaussian noise with said Gaussian noise included in said retransmitted signals, to thereby generate correlation signals representative of the amount of correlation; controlling said step of controllably delaying in response to said correlation signals in a manner which causes said correlation signals to be maximized; and recording at least the amount of delay which results in said maximization of said correlation signals.