Apparatus and method for controlling array antenna comprising a plurality of antenna elements with improved incoming beam tracking
First Claim
1. An apparatus for controlling an array antenna comprising a plurality of antenna elements arranged so as to be adjacent to each other in a predetermined arrangement configuration, the apparatus comprising:
- transforming means for transforming a plurality of received signals received by said antenna elements of said array antenna into respective pairs of quadrature baseband signals, respectively, using a common local oscillation signal, respective quadrature baseband signals of the pairs of quadrature baseband signals being orthogonal to each other;
in-phase putting means, comprising a noise suppressing filter having a predetermined transfer function, said in-phase putting means using a predetermined first axis and a predetermined second axis which are orthogonal to each other and a transformation matrix for putting in phase received signals obtained from each two antenna elements of each combination of said plurality of antenna elements being expressed by a two-by-two transformation matrix including(a) second data on said second axis proportional to a product of a sine value of a phase difference between the received signals obtained from said each two antenna elements of each combination, and respective amplitude values of the received signals thereof, and(b) first data on said first axis proportional to a product of a cosine value of a phase difference between the received signals obtained from said each two antenna elements of each combination, and respective amplitude values of the received signals thereof,said in-phase putting means calculating said first data and said second data based on each pair of transformed quadrature baseband signals, passing the calculated first data and the calculated second data through said noise suppressing filter so as to filter said first and second data and output filtered first and second data, calculating respective element values of said transformation matrix based on the filtered first data and the filtered second data, and putting in phase said received signals obtained from said each two antenna elements of each combination based on said transformation matrix including said calculated transformation matrix elements; and
combining means for combining in phase said plurality of received signals which are put in phase by said in-phase putting means, and outputting an in-phase combined received signal.
3 Assignments
0 Petitions
Accused Products
Abstract
In an apparatus and method for controlling an array antenna comprising a plurality of antenna elements arranged so as to be adjacent to each other in a predetermined arrangement configuration, a plurality of received signals received by the antenna elements is transformed into respective pairs of quadrature baseband signals, using a common local oscillation signal, wherein each pair of quadrature baseband signals is orthogonal to each other. Then predetermined first and second data are calculated based on each pair of transformed quadrature baseband signals, and are filtered using a noise suppressing filter. Respective elements of a transformation matrix for in-phase combining are calculated based on the filtered first and second data, and the received signals obtained from the each two antenna elements are put in phase based on the calculated transformation matrix. Thereafter, a plurality of received signals which are put in phase are combined in phase, and an in-phase combined received signal is outputted.
-
Citations
26 Claims
-
1. An apparatus for controlling an array antenna comprising a plurality of antenna elements arranged so as to be adjacent to each other in a predetermined arrangement configuration, the apparatus comprising:
-
transforming means for transforming a plurality of received signals received by said antenna elements of said array antenna into respective pairs of quadrature baseband signals, respectively, using a common local oscillation signal, respective quadrature baseband signals of the pairs of quadrature baseband signals being orthogonal to each other; in-phase putting means, comprising a noise suppressing filter having a predetermined transfer function, said in-phase putting means using a predetermined first axis and a predetermined second axis which are orthogonal to each other and a transformation matrix for putting in phase received signals obtained from each two antenna elements of each combination of said plurality of antenna elements being expressed by a two-by-two transformation matrix including (a) second data on said second axis proportional to a product of a sine value of a phase difference between the received signals obtained from said each two antenna elements of each combination, and respective amplitude values of the received signals thereof, and (b) first data on said first axis proportional to a product of a cosine value of a phase difference between the received signals obtained from said each two antenna elements of each combination, and respective amplitude values of the received signals thereof, said in-phase putting means calculating said first data and said second data based on each pair of transformed quadrature baseband signals, passing the calculated first data and the calculated second data through said noise suppressing filter so as to filter said first and second data and output filtered first and second data, calculating respective element values of said transformation matrix based on the filtered first data and the filtered second data, and putting in phase said received signals obtained from said each two antenna elements of each combination based on said transformation matrix including said calculated transformation matrix elements; and combining means for combining in phase said plurality of received signals which are put in phase by said in-phase putting means, and outputting an in-phase combined received signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A method for controlling an array antenna comprising a plurality of antenna elements arranged so as to be adjacent to each other in a predetermined arrangement configuration, the method including the steps of:
-
a) transforming a plurality of received signals received by said antenna elements of said array antenna into respective pairs of quadrature baseband signals, respectively, using a common local oscillation signal, respective quadrature baseband signals of the pairs of quadrature baseband signals being orthogonal to each other; b) putting in phase received signals obtained from each two antenna elements of each combination of said plurality of antenna elements by using a predetermined first axis and a predetermined second axis which are orthogonal to each other and a transformation matrix being expressed by a two-by-two transformation matrix including second data on said second axis proportional to a product of a sine value of a phase difference between the received signals obtained from said each two antenna elements of each combination, and respective amplitude values of the received signals thereof, and first data on said first axis proportional to a product of a cosine value of a phase difference between the received signals obtained from said each two antenna elements of each combination, and respective amplitude values of the received signals thereof, said step b) of putting in phase received signals including b1) calculating said first data and said second data based on each pair of transformed quadrature baseband signals, b2) filtering the calculated first data and the calculated second data with a predetermined transfer function so as to provide filtered first and second data, b3) calculating respective element values of said transformation matrix based on the filtered first data and the filtered second data, and b4) putting in phase said received signals obtained from said each two antenna elements of each combination based on said transformation matrix including said calculated transformation matrix elements; and c) combining in phase said plurality of received signals which are put in phase, and providing an in-phase combined received signal. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
-
-
19. An apparatus for controlling an array antenna comprising a plurality of antenna elements arranged so as to be adjacent to each other in a predetermined arrangement configuration, the apparatus comprising:
-
transforming means for transforming a plurality of received signals received by said antenna elements of said array antenna into respective pairs of quadrature baseband signals, using a common local oscillation signal, respective quadrature baseband signals of the pairs of quadrature baseband signals being orthogonal to each other; phase difference calculating means, based on said transformed two quadrature baseband signals transformed by said transforming means, for calculating (a) first data proportional to a product of a cosine value of a phase difference between two received signals obtained from a predetermined reference antenna element and another arbitrary antenna element, and respective amplitude values of said two received signals thereof, (b) second data proportional to a product of a sine value of a phase difference between two received signals obtained from said each two antenna elements of each combination, and respective amplitude values of said two received signals thereof, and c) a reception phase difference between said each two antenna elements of each combination based on the calculated first data and the calculated second data; correcting means for correcting said reception phase difference so that a phase uncertainty generated such that the calculated reception phase difference between each of said two antenna elements of each combination calculated by said phase difference calculating means is limited within a range from -π
to +π
is removed from said reception phase difference, according to a predetermined phase threshold value representing a degree of disorder of a reception phase difference due to a multi-path wave, and for converting a corrected reception phase difference into a transmission phase difference by inverting a sign of said corrected reception phase difference; andtransmitting means for transmitting a transmitting signal from said antenna elements with the transmission phase difference between said each two antenna elements of each combination converted by said correcting means and with the same amplitudes, thereby forming a transmitting main beam only in a direction of a greatest received signal. - View Dependent Claims (20, 21, 22)
-
-
23. A method for controlling an array antenna comprising a plurality of antenna elements arranged so as to be adjacent to each other in a predetermined arrangement configuration, the method comprising the steps of:
-
a) transforming a plurality of received signals received by said antenna elements of said array antenna into respective pairs of quadrature baseband signals, using a common local oscillation signal, respective quadrature baseband signals of the pairs of quadrature baseband signals being orthogonal to each other; b) calculating based on said transformed two quadrature baseband signals first data proportional to a product of a cosine value of a phase difference between two received signals obtained from a predetermined reference antenna element and another arbitrary antenna element, and respective amplitude values of said two received signals thereof, second data proportional to a product of a sine value of a phase difference between two received signals obtained from said each two antenna elements of each combination, and respective amplitude values of said two received signals thereof, and a reception phase difference between said each two antenna elements of each combination based on the calculated first data and the calculated second data; c) correcting said reception phase difference so that a phase uncertainty generated such that the calculated reception phase difference between each of said two antenna elements of each combination is limited within a range from -π
to +π
is removed from said reception phase difference, according to a predetermined phase threshold value representing a degree of disorder of a reception phase difference due to a multi-path wave;d) converting a corrected reception phase difference into a transmission phase difference by inverting a sign of said corrected reception phase difference; and e) transmitting a transmitting signal from said antenna elements with said converted transmission phase difference between said each two antenna elements of each combination and with the same amplitudes, thereby forming a transmitting main beam only in a direction of a greatest received signal. - View Dependent Claims (24, 25, 26)
-
Specification