CDMA communications and geolocation system and method

Claim 2

A spread-spectrum communications and geolocation system for communicating message data comprising: first generic means for generating a generic-chip-code signal; spreading means for spread-spectrum processing the message data, synchronized with the generic chip-code signal, as spread-spectrum-processed-message data; combiner means for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitter means for transmitting, using radio waves traversing free space, the CDMA signal over a communications channel; detection means, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDMA signal, said detection means including, receiving means for receiving the CDMA signal; second generic means, coupled to said receiving means, for detecting the generic-chip-code signal embedded in the CDMA signal and for generating a replica of the generic-chip-code signal; and despreading means, synchronized with the replica of the generic-chip-code signal, for despreading the spread-spectrum-processed-message data as a despread signal; data detection means, synchronized with the replica of the generic-chip-code signal, for detecting message data in the despread signal; and range means, responsive to the detected-generic-chip-code signal and the replica of the generic-chip-code signal, for determining a range delay between the transmitter means and the receiving means.

Claim 3

The spread-spectrum communications and geolocation system as set forth in claim 1 with said despreading means including: a message-chip-code generator for generating a message-chip-code signal synchronized to the replica of the generic-chip-code signal; a product detector for mixing the message-chip-code signal with a received CDMA signal to generate a detected spread-spectrum signal; and a bandpass filter for filtering the detected spread-spectrum signal; and said data detection means includes a data detector, synchronized with the replica of the generic-chip-code signal, for detecting message data in the detected spread-spectrum signal.

Claim 4

A spread-spectrum communications and geolocation system for communicating message data comprising: a generic-chip-code generator for generating a generic-chip-code signal; a spread-spectrum modulator for spread-spectrum processing the message data, synchronized with the generic-chip-code signal, as spread-spectrum-processed-message data; a combiner for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; a transmitter for transmitting, using radio waves traversing free space, the CDMA signal over a communications channel; a detector, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDMA signal, said detector including, a receiver-generic-chip-code generator, synchronized to the detected-generic-chip-code signal, for generating a replica of the generic-chip-code signal; a message-chip-code generator for generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; a product detector for mixing the message-chip-code signal with a received CDMA signal to generate a detected spread-spectrum signal; a bandpass filter for filtering the detected spread-spectrum signal; a data detector, synchronized with the replica of the generic-chip-code signal, for detecting message data in the detected spread-spectrum signal; and a range delay circuit, responsive to timing between the detected-generic-chip-code signal and the replica of the generic-chip-code signal, for determining a range between the transmitter and the detector.

Claim 5

A spread-spectrum communications and geolocation system for communicating message data comprising: a generic-chip-code generator for generating a generic-chip-code signal; a spread-spectrum modulator for spread-spectrum processing the message data, synchronized with the generic-chip-code signal, as spread-spectrum-processed-message data; a combiner for combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; a transmitter for transmitting, using radio waves traversing free space, the CDMA signal over a communications channel; a detector, coupled to said communications channel, for detecting the generic-chip-code signal embedded in the CDMA signal, said detector including, a receiver-generic-chip-code generator, synchronized to the detected-generic-chip-code signal, for generating a replica of the generic-chip-code signal; a message-chip-code generator for generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; a product detector for mixing the message-chip-code signal with a received CDMA signal to generate a detected spread-spectrum signal; a bandpass filter for filtering the detected spread-spectrum signal; a data detector, synchronized with the replica of the generic-chip-code signal, for detecting message data in the detected spread-spectrum signal; and a range delay circuit, responsive to timing between the detected-generic-chip-code signal and the replica of the generic-chip-code signal, for determining a range between the transmitter and the detector.

Claim 6

A spread-spectrum communications and geolocation method for communicating message data, comprising the steps of: generating a generic-chip-code signal; synchronizing the message data with the generic-chip-code signal; spread-spectrum processing the message data as a spread-spectrum-processed-message data; combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the CDMA signal from a transmitter over a communications channel; detecting, from the communications channel on a receiver, the generic-chip-code signal embedded in the CDMA signal; generating, synchronized to the detected-generic-chip-code signal, a replica of the generic-chip-code signal; generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; mixing the message-chip-code signal with a received CDMA signal to generate a detected spread-spectrum signal; filtering the detected spread-spectrum signal; detecting, synchronized to the replica of the generic-chip-code signal, message data in the detected spread-spectrum signal; and determining, using the detected-generic-chip-code signal and the replica of the generic-chip-code signal, a range between the transmitter and the receiver.

Claim 7

A spread-spectrum communications and geolocation method for communicating message data, comprising the steps of: generating a generic-chip-code signal; synchronizing the message data with the generic-chip-code signal; spread-spectrum processing the message data as a spread-spectrum-processed-message data; combining the generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the CDMA signal from a transmitter over a communications channel; detecting, from the communications channel on a receiver, the generic-chip-code signal embedded in the CDMA signal; generating, synchronized to the detected-generic-chip-code signal, a replica of the generic-chip-code signal; generating, synchronized to the replica of the generic-chip-code signal, a message-chip-code signal; mixing the message-chip-code signal with a received CDMA signal to generate a detected spread-spectrum signal; filtering the detected spread-spectrum signal; detecting, synchronized to the replica of the generic-chip-code signal, message data in the detected spread-spectrum signal; and determining, using the detected-generic-chip-code signal and the replica of the generic-chip-code signal, a range between the transmitter and the receiver.

Claim 8

A spread-spectrum communications and geolocation method for communicating message data and determining range between a remote unit and a base station, comprising the steps of: generating a base-generic-chip-code signal; synchronizing base message data with the base-generic-chip-code signal; spread-spectrum processing the base message data as a spread-spectrum-processed-message data; combining the base-generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the CDMA signal from the base station over a communications channel; detecting, from the communications channel at the remote unit, the base-generic-chip-code signal embedded in the CDMA signal; recovering, at the remote unit, the base message data communicated from the base station; generating, at the remote unit, synchronized with the detected-base-generic-chip-code signal, a remote-generic-chip-code signal; spread-spectrum processing remote message data as a spread-spectrum-processed-remote message data; combining the remote-generic-chip-code signal with the spread-spectrum-processed-remote message data, thereby generating a remote code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the remote CDMA signal from the remote unit over a communications channel; detecting, at the base station, the remote-generic-chip-code signal embedded in the remote CDMA signal; recovering, at the base station, the remote message data communicated from the remote unit; and comparing a timing between the base-generic-chip-code signal and the detected remote-generic-chip-code signal to determine a range between the base station and the remote unit.

Claim 9

A spread-spectrum communications and geolocation method for communicating message data and determining range between a remote unit and a base station, comprising the steps of: generating a base-generic-chip-code signal; synchronizing base message data with the base-generic-chip-code signal; spread-spectrum processing the base message data as a spread-spectrum-processed-message data; combining the base-generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the CDMA signal from the base station over a communications channel; detecting, from the communications channel at the remote unit, the base-generic-chip-code signal embedded in the CDMA signal; recovering, at the remote unit, the base message data communicated from the base station; generating, at the remote unit, synchronized with the detected-base-generic-chip-code signal, a remote-generic-chip-code signal; spread-spectrum processing remote message data as a spread-spectrum-processed-remote message data; combining the remote-generic-chip-code signal with the spread-spectrum-processed-remote message data, thereby generating a remote code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the remote CDMA signal from the remote unit over a communications channel; detecting, at the base station, the remote-generic-chip-code signal embedded in the remote CDMA signal; recovering, at the base station, the remote message data communicated from the remote unit; and comparing a timing between the base-generic-chip-code signal and the detected remote-generic-chip-code signal to determine a range between the base station and the remote unit.

Claim 10

A spread-spectrum communications and geolocation method for communicating message data and determining range between a remote unit and a base station, comprising the steps of: generating a base-generic-chip-code signal; synchronizing base message data with the base-generic-chip-code signal; spread-spectrum processing the base message data as a spread-spectrum-processed-message data; combining the base-generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the CDMA signal from the base station over a communications channel; detecting, from the communications channel at the remote unit, the base-generic-chip-code signal embedded in the CDMA signal; recovering, at the remote unit, the base message data communicated from the base station; spread-spectrum processing remote message data as a spread-spectrum-processed-remote message data; combining the detected base-generic-chip-code signal with the spread-spectrum-processed-remote message data, thereby generating a remote code-division-multiple-access (CDMA) signal having a relayed detected-base-generic-chip-code signal; transmitting, using radio waves traversing free space, the remote CDMA signal from the remote unit over a communications channel; detecting, at the base station, the relayed-detected-base-generic-chip-code signal embedded in the remote CDMA signal; recovering, at the base station, the remote message data communicated from the remote unit; and comparing a timing between the base-generic-chip-code signal and the relayed-detected-base-generic-chip-code signal to determine a range between the base station and the remote unit.

Claim 11

A spread-spectrum communications and geolocation method for communicating message data and determining range between a remote unit and a base station, comprising the steps of: generating a base-generic-chip-code signal; synchronizing base message data with the base-generic-chip-code signal; spread-spectrum processing the base message data as a spread-spectrum-processed-message data; combining the base-generic-chip-code signal with the spread-spectrum-processed-message data, thereby generating a code-division-multiple-access (CDMA) signal; transmitting, using radio waves traversing free space, the CDMA signal from the base station over a communications channel; detecting, from the communications channel at the remote unit, the base-generic-chip-code signal embedded in the CDMA signal; recovering, at the remote unit, the base message data communicated from the base station; spread-spectrum processing remote message data as a spread-spectrum-processed-remote message data; combining the detected base-generic-chip-code signal with the spread-spectrum-processed-remote message data, thereby generating a remote code-division-multiple-access (CDMA) signal having a relayed detected-base-generic-chip-code signal; transmitting, using radio waves traversing free space, the remote CDMA signal from the remote unit over a communications channel; detecting, at the base station, the relayed-detected-base-generic-chip-code signal embedded in the remote CDMA signal; recovering, at the base station, the remote message data communicated from the remote unit; and comparing a timing between the base-generic-chip-code signal and the relayed-detected-base-generic-chip-code signal to determine a range between the base station and the remote unit.