Techniques for cophasing elements of a phased antenna array

Claim 1

A method of cophasing each of a plurality of n feed elements which form a phased array antenna at a remote transmitter Characterized in that the method comprises the steps of: during a predetermined recurring interval of time in a transmission sequence, at a receiving station (a) receiving from the remote transmitter a lower sideband reference signal of a first signal (ω c ) modulated with a second signal (ω p ) which was transmitted by a first one of the feed elements of the transmitting phased array antenna; (b) concurrent with step (a), receiving from the remote transmitter an upper sideband signal of the first signal (ω c ) modulated by the second signal (ω p ) which was transmitted by a second one of the feed elements of the transmitting phased array antenna; (c) measuring and storing the phase angle between the upper and lower sideband signals received in steps (a) and (b) which is representative of the phase setting between the first and second one of the feed elements which transmitted the lower and upper sideband signals, respectively; (d) reiterating step (a); (e) concurrent with step (d), receiving from the remote transmitter an upper sideband signal of the first signal (ω c ) modulated by the second signal (ω p ) which was transmitted by a third one of the feed elements of the transmitting phased array antenna; (f) measuring the phase angles between the upper and lower sideband signals received in steps (d) and (e) which is representative of the phase setting between the first and said third one of the feed elements; (g) determining the difference between the phase angles measured in steps (c) and (f), which difference is representative of the actual phase setting for said third one of the feed elements used in step (e) with respect to the second one of the feed elements used in step (c); and (h) transmitting the actual phase setting obtained in step (g) back to the remote transmitter for subsequent use in transmitting signals back to the receiving station.

Claim 2

A method of cophasing each of a plurality of n feed elements which form a phased array antenna at a remote transmitter Characterized in that the method comprises the steps of: during a predetermined recurring interval of time in a transmission sequence, at a receiving station (a) receiving from the remote transmitter a lower sideband reference signal of a first signal (ω c ) modulated with a second signal (ω p ) which was transmitted by a first one of the feed elements of the transmitting phased array antenna; (b) concurrent with step (a), receiving from the remote transmitter an upper sideband signal of the first signal (ω c ) modulated by the second signal (ω p ) which was transmitted by a second one of the feed elements of the transmitting phased array antenna; (c) measuring and storing the phase angle between the upper and lower sideband signals received in steps (a) and (b) which is representative of the phase setting between the first and second one of the feed elements which transmitted the lower and upper sideband signals, respectively; (d) reiterating step (a); (e) concurrent with step (d), receiving from the remote transmitter an upper sideband signal of the first signal (ω c ) modulated by the second signal (ω p ) which was transmitted by a third one of the feed elements of the transmitting phased array antenna; (f) measuring the phase angles between the upper and lower sideband signals received in steps (d) and (e) which is representative of the phase setting between the first and said third one of the feed elements; (g) determining the difference between the phase angles measured in steps (c) and (f), which difference is representative of the actual phase setting for said third one of the feed elements used in step (e) with respect to the second one of the feed elements used in step (c); and (h) transmitting the actual phase setting obtained in step (g) back to the remote transmitter for subsequent use in transmitting signals back to the receiving station.

Claim 8

A method of cophasing a plurality of n feed elements which form a phase array antenna at a receiving station, the method comprising the step of: during a predetermined receiving interval of time, (a) receiving at each of the plurality of n feed elements a first signal (ω c ) arriving from a particular direction; Characterized in that the method comprises the further steps of: (b) modulating the first signal (ω c ) received by a first one of the plurality of n feed elements (e.g., 22 1 ) with a second signal (ω p ) to produce a lower sideband reference signal thereof; (c) concurrent with step (b), modulating the first signal (ω c ) received by a second one of the plurality of n feed elements (e.g., 22 2 ) with the second signal (ω p ) to produce an upper sideband signal thereof; (d) measuring and storing the phase angle between the upper and lower sideband signals generated in steps (b) and (c) which is representative of the phase settings between the first and second one of the feed elements; (e) reiterating step (b); (f) concurrent with step (e), modulating the first signal (ω c ) received by a third one of the plurality of n feed elements with the second signal (ω p ) to produce an upper sideband signal thereof; (g) measuring the phase angle between the upper and lower sideband signals generated in steps (e) and (f) which is representative of the phase setting between the first one and said third one of the plurality of n feed elements; and (h) determining the difference between the phase angles measured in steps (d) and (g), which difference is representative of the actual phase setting for said third one of the feed elements used in step (f) with respect to the second one of the feed elements used in step (d).

Claim 9

A method of cophasing a plurality of n feed elements which form a phase array antenna at a receiving station, the method comprising the step of: during a predetermined receiving interval of time, (a) receiving at each of the plurality of n feed elements a first signal (ω c ) arriving from a particular direction; Characterized in that the method comprises the further steps of: (b) modulating the first signal (ω c ) received by a first one of the plurality of n feed elements (e.g., 22 1 ) with a second signal (ω p ) to produce a lower sideband reference signal thereof; (c) concurrent with step (b), modulating the first signal (ω c ) received by a second one of the plurality of n feed elements (e.g., 22 2 ) with the second signal (ω p ) to produce an upper sideband signal thereof; (d) measuring and storing the phase angle between the upper and lower sideband signals generated in steps (b) and (c) which is representative of the phase settings between the first and second one of the feed elements; (e) reiterating step (b); (f) concurrent with step (e), modulating the first signal (ω c ) received by a third one of the plurality of n feed elements with the second signal (ω p ) to produce an upper sideband signal thereof; (g) measuring the phase angle between the upper and lower sideband signals generated in steps (e) and (f) which is representative of the phase setting between the first one and said third one of the plurality of n feed elements; and (h) determining the difference between the phase angles measured in steps (d) and (g), which difference is representative of the actual phase setting for said third one of the feed elements used in step (f) with respect to the second one of the feed elements used in step (d).