JP7463205B2 - Electronically scanned antenna and signal processing method thereof - Google Patents

Description

This embodiment of the invention relates to an electronically scanned antenna and its signal processing method.

In conventional electronically scanned antennas, multiple antenna elements are arranged in a planar array, and multiple transmit/receive modules that process transmission and reception by combining the multiple antennas are installed side by side. A distributor/synthesizer distributes and distributes the transmission signal to each transmit/receive module, and outputs a composite signal from each transmit/receive module. However, since both the transmit beam and receive beam are set to one direction, and the transmit and receive frequencies are the same for all antenna elements, there is a problem in that it is not possible to track multiple targets simultaneously.

Japanese Patent Application Laid-Open No. 06-331720 Japanese Patent Application Laid-Open No. 11-330839 JP 2002-527971 A

As described above, with conventional electronically scanned antenna configurations, both the transmit and receive beams are set in one direction, and the transmit and receive frequencies are the same for all antenna elements, which means that multiple targets cannot be tracked simultaneously.

The objective of the present invention is to provide a multi-beam electronically scanned antenna and its signal processing method that maintains the functionality and performance of a conventional single-beam electronically scanned antenna while allowing the frequency to be changed for each beam and enabling multiple targets to be tracked simultaneously.

According to the electronically scanned antenna of the embodiment, the antenna is equipped with a four-element integrated transceiver module that performs transmission and reception processing for each of the first and second antenna elements and the third and fourth antenna elements, outputs a first composite signal by combining the received signals of each of the first and second antenna elements, and outputs a second composite signal by combining the received signals of each of the third and fourth antenna elements, and a distributor/synthesizer comparator that distributes and compares the first composite signal and the second composite signal output from the transceiver module to form multiple composite beams. The splitter/synthesizer comparator includes a first 2-way splitter that splits a first composite signal obtained by the transmission/reception module into two, a second 2-way splitter that splits a second composite signal obtained by the transmission/reception module into two, a first comparator with a 90° hybrid to which a first output of the first 2-way splitter and a first output of the second 2-way splitter are connected and which divides all antenna elements to form multiple beams, a second comparator with a combiner and a 90° hybrid to which a second output of the first 2-way splitter and a second output of the second 2-way splitter are connected and which forms a composite beam of all antenna elements, and a transmission signal supplying means that supplies the transmission/reception module with multiple independent transmission signals of arbitrary frequencies for each beam. That is, the reception signal of the transmission/reception module is split into two by the 2-way splitter in the splitter/synthesizer comparator, and one signal is connected to a system of a comparison combiner with a combiner and a 90° hybrid so as to form a composite beam of all antenna elements, and the other signal is connected to a system constituting a comparison combiner with a combiner and a 90° hybrid so as to form multiple beams. This makes it possible to change the frequency for each beam while maintaining the function and performance of a conventional one-beam electronically scanned antenna.

FIG. 1 is a block diagram showing the configuration of an electronically scanned antenna according to the first embodiment. FIG. 2 is a plan view showing an array of antenna elements of an electronically scanned antenna to which the embodiment is applied. FIG. 3 is a block diagram showing an internal system of a transmitting/receiving module of an electronically scanned antenna to which the embodiment is applied. FIG. 4 is a block diagram showing an internal system of a 3-bit MMIC phase shifter integrated with an RF switch of an electronically scanned antenna to which the embodiment is applied. FIG. 5 is a block diagram showing the configuration of an electronically scanned antenna according to the second embodiment.

Hereinafter, an embodiment will be described with reference to the drawings.
First Embodiment
FIG. 1 shows the configuration of an electronically scanned antenna according to a first embodiment, and FIGS. 2 to 4 respectively show the antenna element arrangement of an electronically scanned antenna to which this embodiment is applied, the internal system of a transmission/reception module, and the internal system of a 3-bit MMIC phase shifter integrated with an RF switch.

In Fig. 1, the antenna element 1 is shared by transmission and reception (RF_IN/OUT), and is arranged in 8 rows and 8 columns in the EL and AZ directions as shown in Fig. 2. It is divided into units of 4 elements arranged in one column in the same direction, and each is connected to the 1st to 16th transmission and reception modules 2 (No. 1 to No. 16) that are integrated with 4 elements. The transmission and reception modules 2 are capable of independent phase control by an internal phase shifter, and can form transmission beams and reception beams in any direction by phase control, transmit radio waves in the direction in which the transmission beam is formed, and receive radio waves arriving from the direction in which the reception beam is formed.

As shown in FIG. 3, the first transceiver module 2 (No. 1) has first to fourth module units 2-1 to 2-4 corresponding to the first to fourth antenna elements 1. The first to fourth module units 2-1 to 2-4 have the same configuration.

The configuration of the first module unit 2-1 will be described. This first module unit 2-1 includes a phase shifter (PS) 2-11 that controls the phase of the transmission and reception signals, a TX/RX switch (SPDT) 2-12 that switches between transmission and reception, an intermediate amplifier (MPA) 2-13 that intermediately amplifies the transmission signal, a driver (DRV) 2-14 for pulse driving, an attenuator (ATT) 2-15 for adjusting the output gain, a high-power amplifier (HPA) 2-16 that power amplifies the transmission signal, a circulator (CIR) 2-17, a band-limiting filter (BEF) 2-18 that removes unwanted waves, a limiter (LIM) 2-19 that limits the gain of the reception signal, a low-noise amplifier (LNA) 2-1A that amplifies the reception signal with low noise, RF switches (SPDT) 2-1B1, 2-1B2 that control the on/off of the LNA before and after it, and an intermediate amplifier (MPA) 2-1C that intermediately amplifies the reception signal.

The transmission/reception input/output terminals of the first and second module units 2-1 and 2-2 are connected to the first and second terminals of a 2-combiner (2-distributor in the transmission system) 2-51 of the A system, respectively, and the third terminal of this 2-combiner 2-51 is connected to the transmission/reception terminal (T/R-A) of the A system. In addition, the transmission/reception input/output terminals of the third and fourth module units 2-3 and 2-4 are connected to the first and second terminals of a 2-combiner (2-distributor in the transmission system) 2-52 of the B system, and the third terminal of this 2-combiner 2-52 is connected to the transmission/reception terminal (T/R-B) of the B system. The second to sixteenth transmission/reception modules 2 (No. 2 to No. 16) have the same configuration as the first transmission/reception module 2 (No. 1).

The two transmitting/receiving terminals (T/R-A, T/R-B) of the first transmitting/receiving module 2 (No. 1) are respectively connected to the first terminals of the first and second 2-way distributors (2-way combiners in the transmitting system) 3-11, 3-12 of the distributor/composer comparator 3. The second terminals of the first and second 2-way distributors (2-way combiners in the transmitting system) 3-11, 3-12 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the first 2-way combiner 3-21. The third terminal of the first 2-way combiner 3-21 is connected to the first terminal of the first EL comparator combiner 3-31 by a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the second transmitting/receiving module 2 (No. 2) are respectively connected to the first terminals of the third and fourth 2-way distributors (2-way combiners in the transmission system) 3-13, 3-14 of the distributor/synthesizer comparator 3. The second terminals of the third and fourth 2-way distributors (2-way combiners in the transmission system) 3-13, 3-14 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the second 2-way combiner 3-22. The third terminal of the second 2-way combiner 3-22 is connected to the first terminal of the second EL comparator combiner 3-32 using a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the third transmitting/receiving module 2 (No. 3) are respectively connected to the first terminals of the fifth and sixth 2-way distributors (2-way combiners in the transmission system) 3-15, 3-16 of the distributor/composer comparator 3. The second terminals of the fifth and sixth 2-way distributors (2-way combiners in the transmission system) 3-15, 3-16 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the third 2-way combiner 3-23. The third terminal of the third 2-way combiner 3-23 is connected to the first terminal of the third EL comparator combiner 3-33 using a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the fourth transmitting/receiving module 2 (No. 4) are respectively connected to the first terminals of the seventh and eighth 2-way distributors (2-way combiners in the transmission system) 3-17, 3-18 of the distributor/composer comparator 3. The second terminals of the seventh and eighth 2-way distributors (2-way combiners in the transmission system) 3-17, 3-18 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the fourth 2-way combiner 3-24. The third terminal of the fourth 2-way combiner 3-24 is connected to the first terminal of the fourth EL comparator combiner 3-34 using a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the fifth transmitting/receiving module 2 (No. 5) are connected to the first terminals of the ninth and tenth 2-way distributors (2-way combiners in the transmission system) 3-19, 3-110 of the distributor/composer comparator 3. The second terminals of the ninth and tenth 2-way distributors (2-way combiners in the transmission system) 3-19, 3-110 are for the second embodiment, and the third terminals are connected to the first and second terminals of the fifth 2-way combiner 3-25, respectively. The third terminal of the fifth 2-way combiner 3-25 is connected to the first terminal of the fifth EL comparison combiner 3-35 by a 90° hybrid.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the sixth transmitting/receiving module 2 (No. 6) are respectively connected to the first terminals of the first and twelfth 2-way distributors (2-way combiners in the transmission system) 3-111, 3-112 of the distributor/synthesizer comparator 3. The second terminals of the eleventh and twelfth 2-way distributors (2-way combiners in the transmission system) 3-111, 3-112 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the sixth 2-way combiner 3-26. The third terminal of the sixth 2-way combiner 3-26 is connected to the first terminal of the sixth EL comparator/synthesizer 3-36 by a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the seventh transmitting/receiving module 2 (No. 7) are respectively connected to the first terminals of the 13th and 14th 2-way distributors (2-way combiners in the transmission system) 3-113, 3-114 of the distributor/composer comparator 3. The second terminals of the 13th and 14th 2-way distributors (2-way combiners in the transmission system) 3-113, 3-114 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the seventh 2-way combiner 3-27. The third terminal of the seventh 2-way combiner 3-27 is connected to the first terminal of the seventh EL comparator/composer 3-37 by a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the eighth transmitting/receiving module 2 (No. 8) are respectively connected to the first terminals of the 15th and 16th 2-way distributors (2-way combiners in the transmission system) 3-115, 3-116 of the distributor/composer comparator 3. The second terminals of the 15th and 16th 2-way distributors (2-way combiners in the transmission system) 3-115, 3-116 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the eighth 2-way combiner 3-28. The third terminal of the eighth 2-way combiner 3-28 is connected to the first terminal of the eighth EL comparison combiner 3-38 by a 90° hybrid.

The two transmitting/receiving ends (T/R-A, T/R-B) of the ninth transmitting/receiving module 2 (No. 9) are respectively connected to the first terminals of the 17th and 18th 2-way distributors (2-way combiners in the transmitting system) 3-117, 3-118 of the distributor/combiner comparator 3. The second terminals of the 17th and 18th 2-way distributors (2-way combiners in the transmitting system) 3-117, 3-118 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the ninth 2-way combiner 3-29. The third terminal of the ninth 2-way combiner 3-28 is connected to the second terminal of the first EL comparator/combiner 3-31.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the tenth transmitting/receiving module 2 (No. 10) are respectively connected to the first terminals of the nineteenth and twentieth two-way distributors (two-way combiners in the transmitting system) 3-119, 3-120 of the distributor/synthesizer comparator 3. The second terminals of the nineteenth and twentieth two-way distributors (two-way combiners in the transmitting system) 3-119, 3-120 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the tenth two-way combiner 3-210. The third terminal of the tenth two-way combiner 3-210 is connected to the second terminal of the second EL comparator/synthesizer 3-32.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the eleventh transmitting/receiving module 2 (No. 11) are respectively connected to the first terminals of the 21st and 22nd 2-way distributors (2-way combiners in the transmitting system) 3-121, 3-122 of the distributor/synthesizer comparator 3. The second terminals of the 21st and 22nd 2-way distributors (2-way combiners in the transmitting system) 3-121, 3-122 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the eleventh 2-way combiner 3-211. The third terminal of the eleventh 2-way combiner 3-211 is connected to the second terminal of the third EL comparator/synthesizer 3-33.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the 12th transmitting/receiving module 2 (No. 12) are respectively connected to the first terminals of the 23rd and 24th 2-way distributors (2-way combiners in the transmission system) 3-123, 3-124 of the distributor/synthesizer comparator 3. The second terminals of the 23rd and 24th 2-way distributors (2-way combiners in the transmission system) 3-123, 3-124 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the 12th 2-way combiner 3-212. The third terminal of the 12th 2-way combiner 3-212 is connected to the second terminal of the fourth EL comparator/synthesizer 3-34.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the 13th transmitting/receiving module 2 (No. 13) are respectively connected to the first terminals of the 25th and 26th 2-way distributors (2-way combiners in the transmission system) 3-125, 3-126 of the distributor/composer comparator 3. The second terminals of the 25th and 26th 2-way distributors (2-way combiners in the transmission system) 3-125, 3-126 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the 13th 2-way combiner 3-213. The third terminal of the 13th 2-way combiner 3-213 is connected to the second terminal of the 5th EL comparator/composer 3-35.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the 14th transmitting/receiving module 2 (No. 14) are respectively connected to the first terminals of the 27th and 28th 2-way distributors (2-way combiners in the transmitting system) 3-127, 3-128 of the distributor/combiner comparator 3. The second terminals of the 27th and 28th 2-way distributors (2-way combiners in the transmitting system) 3-127, 3-128 are for the second embodiment, and the third terminals are respectively connected to the first and second terminals of the 14th 2-way combiner 3-214. The third terminal of the 14th 2-way combiner 3-214 is connected to the second terminal of the 6th EL comparator/combiner 3-36.

The two transmitting/receiving terminals (T/R-A, T/R-B) of the fifteenth transmitting/receiving module 2 (No. 15) are connected to the first terminals of the twenty-ninth and thirty-ninth two-way distributors (two-way combiners in the transmission system) 3-129, 3-130 of the distributor/combiner comparator 3. The second terminals of the twenty-ninth and thirty-ninth two-way distributors (two-way combiners in the transmission system) 3-129, 3-130 are for the second embodiment, and the third terminals are connected to the first and second terminals of the fifteenth two-way combiner 3-215, respectively. The third terminal of the fifteenth two-way combiner 3-215 is connected to the second terminal of the seventh EL comparator/combiner 3-37.

The two transmitting/receiving ends (T/R-A, T/R-B) of the 16th transmitting/receiving module 2 (No. 16) are connected to the first terminals of the 31st and 32nd 2-way distributors (2-way combiners in the transmission system) 3-131, 3-132 of the distributor/combiner comparator 3. The second terminals of the 31st and 32nd 2-way distributors (2-way combiners in the transmission system) 3-131, 3-132 are for the second embodiment, and the third terminals are connected to the first and second terminals of the 16th 2-way combiner 3-216, respectively. The third terminal of the 16th 2-way combiner 3-215 is connected to the second terminal of the 8th EL comparator/combiner 3-38.

The third terminals (EL1 to EL8 output terminals) of the first to eighth EL comparators 3-31 to 3-38 are respectively connected to the first to eighth terminals of the 8-combiner 3-4. The ninth terminal of the 8-combiner 3-4 is connected to the EL output terminal. The fourth terminals of the first to fourth EL comparators 3-31 to 3-34 are respectively connected to the first to fourth terminals of the first 4-combiner 3-51 via the first to fourth circulators 3-41 to 3-44, and the fourth terminals of the fifth to eighth EL comparators 3-35 to 3-38 are respectively connected to the first to fourth terminals of the second 4-combiner 3-52 via the fifth to eighth circulators 3-45 to 3-48. The fifth terminals of the first and second 4-combiners 3-51 and 3-52 are respectively connected to the first and second terminals of the AZ comparator 3-6. The third terminal of the AZ comparison combiner 3-6 is connected to the Σ output terminal, and the fourth terminal is connected to the AZ output terminal.

The first to eighth circulators 3-41 to 3-48 are each supplied with a signal that is obtained by splitting the transmission signal input from the TX input terminal into eight by the eight-way splitter 3-7.

The phase shifter (PS) 2-11 and TX/RX switch (SPDT) 2-12 of the module unit 2-1 (2-2 to 2-4 are also the same) are integrated as shown within the dashed line in Figure 3, and are realized as a 3-bit digital phase shifter 2-1D with an integrated RF switch using an MMIC (monolithic microwave integrated circuit).

Figure 4 is a block diagram showing the internal system of the RF switch integrated 3-bit MMIC phase shifter 2-1D. This phase shifter 2-1D has a typical 3-bit configuration, and the phase is switched in 45-degree steps by switching the SPDT RF switches SW11, SW12, SW21, SW12, SW31, and SW12 arranged in front and behind a line with a phase difference of 45 degrees (L1), a line with a phase difference of 90 degrees (L2), and a line with a phase difference of 180 degrees (L3). Furthermore, the MMIC phase shifter 2-1D has a built-in TX/RX changeover switch (SPDT) 2-12. In this case, since the MMIC already has many built-in RF switches for line switching, the manufacturing cost of the MMIC hardly increases.

When the transmission signal TX is input to the electronically scanned antenna with the above configuration, it is distributed by the 8-way distributor 3-7 into 8 transmission signals TX1 to TX8, which are then input to the fourth terminals of the 1st to 8th EL comparators 3-31-1 to 3-38 via the 1st to 8th circulators 3-41 to 3-48, respectively, and distributed from their first terminals to the third terminals of the 1st to 8th 2-combiners 3-21 to 3-28 of the first group, and distributed from their second terminals to the 9th to 16th 2-combiners 3-29 to 3-216 of the second group.

The transmission signals input to the first through eighth 2-combiners 3-21 through 3-28 of the first group are distributed to system A and system B, and are supplied to system A and system B of the first through eighth transceiver modules 2 (No. 1 through No. 8) via the first through sixteenth 2-distributors 3-11 through 3-116, respectively.

The transmission signals input to the 9th to 16th 2-combiners 3-29 to 3-216 of the second group are distributed to system A and system B, and are supplied to system A and system B of the 9th to 16th transmission/reception modules 2 (No. 9 to No. 16) via the 17th to 32nd 2-distributors 3-117 to 3-132, respectively.

In each transmission/reception module 2, the transmission signal input from the transmission/reception input/output terminal of the A system is distributed to two systems by the two-way combiner 2-51. One transmission signal is input to the first module unit 2-1, phase-controlled by the phase shifter (PS) 2-11, passes through the TX/RX changeover switch (SPDT) 2-12 when the switch is set to transmission, is intermediately amplified by the transmission system intermediate amplifier (MPA) 2-13, is pulse-driven by the driver (DRV) 2-14, is gain-adjusted by the attenuator (ATT) 2-15, is power-amplified by the high-power amplifier (HPA) 2-16, passes through the circulator (CIR) 2-17, is band-limited by the band-limiting filter (BEF) 2-18, and is transmitted from the antenna element 1. The other transmission signal is input to the second module unit 2-2 and is processed in the same manner as the first module unit 2-1.

In the first module unit 2-1, the reception signal of the antenna element 1 is band-limited by the band-limiting filter (BEF) 2-18, passes through the circulator (CIR) 2-17, is gain-limited by the limiter (LIM) 2-19, is amplified with low noise by the low-noise amplifier (LNA) 2-1A, the LNA is turned off by the RF switch (SPDT) 2-1B as necessary, is intermediately amplified by the reception system intermediate amplifier (MPA) 2-1C, and is output from the transmission/reception input/output terminal after being phase-controlled by the phase shifter (PS) 2-11 when reception is selected by the TX/RX changeover switch (SPDT) 2-12. In the second module unit 2-2, the reception signal of the antenna element 1 is processed in the same manner as the first module unit 2-1. The reception signals of the first and second module units 2-1 and 2-2 are combined by the 2-combiner 2-51 and output as the A system reception signal.

The processing of the A system is the same for the B system, and the transmission signal input from the transmission/reception input/output terminal of the B system is split into two systems by the 2-way combiner 2-52 and then transmitted via the third and fourth module units 2-3 and 2-4. The respective reception signals are combined by the 2-way combiner 2-52 via the third and fourth module units 2-3 and 2-4 and output as the B system reception signal.

The A-system reception signals and B-system reception signals obtained in the first to eighth transmission/reception modules 2 are respectively supplied to the distribution/combination comparator 3, and are divided into two by the first to sixteenth two-way distributors 3-11 to 3-116. The A-system reception signals and B-system reception signals output from the third terminal are combined by the first to eighth two-way combiners 3-21 to 3-28 and supplied to the first terminals of the first to eighth EL comparison combiners 3-31 to 3-38. The A-system reception signals and B-system reception signals obtained in the ninth to sixteenth transmission/reception modules 2 are respectively supplied to the distribution/combination comparator 3, and are divided into two by the seventeenth to thirty-second two-way distributors 3-117 to 3-132. The A-system reception signals and B-system reception signals output from the third terminal are combined by the ninth to sixteenth two-way combiners 3-29 to 3-216 and supplied to the second terminals of the first to eighth EL comparison combiners 3-31 to 3-38.

The composite signals output from the third terminals of the first to eighth EL comparators and combiners 3-31 to 3-38 are combined in the 8-combiner 3-4 and output from the EL output terminal.

The composite signals output from the fourth terminals of the first to eighth EL comparators 3-31 to 3-38 are supplied to the first to fourth terminals of the first 4-combiner 3-51 via the first to fourth circulators 3-41 to 3-44, respectively, and the fourth terminals of the fifth to eighth EL comparators 3-35 to 3-38 are supplied to the first to fourth terminals of the second 4-combiner 3-52 via the fifth to eighth circulators 3-45 to 3-48, respectively. The received signals combined by the first and second 4-combiners 3-51 and 3-52 are supplied to the first and second terminals of the AZ comparator combiner 3-6, respectively, and a Σ signal is output from the third terminal of the AZ comparator combiner 3-6, and an AZ composite signal is output from the fourth terminal, functioning as a one-beam electronic scanning antenna.

Second Embodiment
Fig. 5 is a block diagram showing the configuration of an electronic scanning antenna according to the second embodiment, in which the same parts as those in Fig. 1 are denoted by the same reference numerals and overlapping explanations will be omitted.

In this electronically scanned antenna, as shown by dotted lines in Figures 2 and 3, the entire antenna with 8 rows and 8 columns is divided into four in the EL and AZ directions to form the first to fourth antennas ANT#1 to ANT#4.

The first antenna ANT#1 comprises first to fourth transmitting/receiving modules 2 (No. 1 to No. 4). The two transmitting/receiving ends (T/R-A, T/R-B) of each of the first to fourth transmitting/receiving modules 2 (No. 1 to No. 4) are connected to first terminals of the first and second 2-way splitters 3-11, 3-12, the third and fourth 2-way splitters 3-13, 3-14, the fifth and sixth 2-way splitters 3-15, 3-16, and the seventh and eighth 2-way splitters 3-17, 3-18 of the distribution/combining comparator 3. The second terminals of the pairs of the first and second 2-way splitters 3-11 to 3-12, the third and fourth 2-way splitters 3-13, 3-14, the fifth and sixth 2-way splitters 3-15, 3-16, and the seventh and eighth 2-way splitters 3-17, 3-18 are connected to the first and second terminals of the corresponding first to fourth EL comparison and synthesis devices 3-31 to 3-34, and the third terminals are for the first embodiment. The third terminals of the first to fourth EL comparison and synthesis devices 3-31 to 3-34 are connected to the first to fourth terminals of the first 4-way combiner 3-81. The fifth terminal of the first 4-way combiner 3-81 is connected to the ANT#1_EL output terminal. The fourth terminals of the first to fourth EL comparators and combiners 3-31 to 3-34 are connected in sequence to the first and second terminals of the first 2 combiner 3-91 and the first and second terminals of the second 2 combiner 3-92 via the circulators 3-41 to 3-44. The third terminals of the first and second 2 combiners 3-91 and 3-92 are respectively connected to the first and second terminals of the first AZ comparator and combiner 3-A1 by a 90° hybrid, the third terminal of the first AZ comparator and combiner 3-A1 is connected to the ANT#1_Σ output terminal, and the fourth terminal is connected to the ANT#1_AZ output terminal. The circulators 3-41 to 3-44 are respectively connected to the first to fourth terminals of the first 4-way divider 3-B1. The fifth terminal of the first 4-way divider 3-B1 is connected to the input terminal of the transmission signal TX#1 for the first antenna.

The second antenna ANT#2 comprises fifth to eighth transmitting/receiving modules 2 (No. 5 to No. 8). The two transmitting/receiving ends (T/R-A, T/R-B) of each of the fifth to eighth transmitting/receiving modules 2 (No. 5 to No. 8) are connected to first terminals of the ninth and tenth 2-way splitters 3-19, 3-110, the eleventh and twelfth 2-way splitters 3-111, 3-112, the thirteenth and fourteenth 2-way splitters 3-113, 3-114, and the fifteenth and sixteenth 2-way splitters 3-115, 3-116 of the distribution/combining comparator 3. The second terminals of the ninth and tenth 2-way dividers 3-19, 3-110, the eleventh and twelfth 2-way dividers 3-111, 3-112, the thirteenth and fourteenth 2-way dividers 3-113, 3-114, and the fifteenth and sixteenth 2-way dividers 3-115, 3-116, which are paired, are connected to the first and second terminals of the corresponding fifth to eighth EL comparison combiners 3-35 to 3-38, respectively, and the third terminals are for the first embodiment. The third terminals of the fifth to eighth EL comparison combiners 3-35 to 3-38 are connected to the first to fourth terminals of the second four-way combiner 3-82. The fifth terminal of the second four-way combiner 3-82 is connected to the ANT#2_EL output terminal. The fourth terminals of the fifth to eighth EL comparators and combiners 3-35 to 3-38 are connected in sequence to the first and second terminals of the third 2 combiner 3-93 and the first and second terminals of the fourth 2 combiner 3-94 via the circulators 3-45 to 3-48. The third terminals of the third and fourth 2 combiners 3-93 and 3-94 are respectively connected to the first and second terminals of the second AZ comparator and combiner 3-A2 by a 90° hybrid, the third terminal of the second AZ comparator and combiner 3-A2 is connected to the ANT#2_Σ output terminal, and the fourth terminal is connected to the ANT#2_AZ output terminal. The above circulators 3-45 to 3-48 are respectively connected to the first to fourth terminals of the second 4-way divider 3-B2. The fifth terminal of the second 4-way divider 3-B2 is connected to the input terminal of the transmission signal TX#2 for the second antenna.

The third antenna ANT#3 comprises ninth to twelfth transmitting/receiving modules 2 (No. 9 to No. 12). The two transmitting/receiving ends (T/R-A, T/R-B) of each of the ninth to twelfth transmitting/receiving modules 2 (No. 9 to No. 12) are connected to the first terminals of the 17th and 18th 2-way splitters 3-117, 3-118, the 19th and 20th 2-way splitters 3-119, 3-120, the 21st and 22nd 2-way splitters 3-121, 3-122, and the 23rd and 24th 2-way splitters 3-123, 3-124 of the distribution/combining comparator 3. The second terminals of the pair of the 17th and 18th 2-way dividers 3-117, 3-118, the 19th and 20th 2-way dividers 3-119, 3-120, the 21st and 22nd 2-way dividers 3-121, 3-122, and the 23rd and 24th 2-way dividers 3-123, 3-124 are connected to the first and second terminals of the corresponding 9th to 12th EL comparison combiners 3-39 to 3-312, respectively, and the third terminals are for the first embodiment. The third terminals of the 9th to 12th EL comparison combiners 3-39 to 3-312 are connected to the first to fourth terminals of the third 4-way combiner 3-83. The fifth terminal of the third 4-way combiner 3-83 is connected to the ANT#3_EL output terminal. The fourth terminals of the ninth to twelfth EL comparators and combiners 3-39 to 3-312 are connected in sequence to the first and second terminals of the fifth 2 combiner 3-95 and the first and second terminals of the sixth 2 combiner 3-96 via the circulators 3-49 to 3-412. The third terminals of the fifth and sixth 2 combiners 3-95 and 3-96 are respectively connected to the first and second terminals of the third AZ comparator and combiner 3-A3 by a 90° hybrid, the third terminal of the third AZ comparator and combiner 3-A3 is connected to the ANT#3_Σ output terminal, and the fourth terminal is connected to the ANT#3_AZ output terminal. The above circulators 3-49 to 3-412 are respectively connected to the first to fourth terminals of the third 4-way divider 3-B3. The fifth terminal of the third 4-way divider 3-B3 is connected to the input terminal of the transmission signal TX#3 for the second antenna.

The fourth antenna ANT#4 comprises thirteenth to sixteenth transmitting/receiving modules 2 (No. 13 to No. 16). The two transmitting/receiving ends (T/R-A, T/R-B) of each of the thirteenth to sixteenth transmitting/receiving modules 2 (No. 13 to No. 16) are connected to first terminals of the twenty-fifth and twenty-sixth two-way splitters 3-125, 3-126, the twenty-seventh and twenty-eighth two-way splitters 3-127, 3-128, the twenty-ninth and thirtieth two-way splitters 3-129, 3-130, and the thirty-first and thirty-second two-way splitters 3-131, 3-132 of the distribution/combining comparator 3. The second terminals of the pairs of the 25th and 26th 2-way dividers 3-125, 3-126, the 27th and 28th 2-way dividers 3-127, 3-128, the 29th and 30th 2-way dividers 3-129, 3-130, and the 31st and 32nd 2-way dividers 3-131, 3-132 are connected to the first and second terminals of the corresponding 13th to 16th EL comparison and synthesis devices 3-313 to 3-316, respectively, and the third terminals are for the first embodiment. The third terminals of the 13th to 16th EL comparison and synthesis devices 3-313 to 3-316 are connected to the first to fourth terminals of the fourth 4-way combiner 3-84. The fifth terminal of the fourth 4-way combiner 3-84 is connected to the ANT#4_EL output terminal. The fourth terminals of the thirteenth to sixteenth EL comparators and combiners 3-313 to 3-316 are connected in sequence to the first and second terminals of the seventh 2 combiner 3-97 and the first and second terminals of the eighth 2 combiner 3-98 via the circulators 3-413 to 3-416. The third terminals of the seventh and eighth 2 combiners 3-97 and 3-98 are respectively connected to the first and second terminals of the fourth AZ comparator and combiner 3-A4 by a 90° hybrid, the third terminal of the fourth AZ comparator and combiner 3-A4 is connected to the ANT#4_Σ output terminal, and the fourth terminal is connected to the ANT#4_AZ output terminal.

In the electronically scanned antenna with the above configuration, the transmission signal is individually provided to the first through fourth antennas ANT#1 through ANT#4 at any frequency, and is output from each antenna via the corresponding distributor/synthesizer and transceiver module.

On the other hand, for reception, the first antenna ANT#1 compares the received signals of the A system and the B system of the first to fourth transmission/reception modules (No. 1 to No. 4) in the first to fourth EL comparators and combiners 3-31 to 3-34, and combines the comparison outputs in the first four-combiner 3-81 to obtain the ANT#1EL signal. Also, the combined signal of the comparison outputs of the first and second EL comparators and combiners 3-31, 3-32 and the combined signal of the comparison outputs of the third and fourth EL comparators and combiners 3-33, 3-34 are compared in the first AZ comparator and combiner 3-A1 to obtain the ANT#1Σ signal and the ANT#1AZ signal.

Similarly, in the second antenna ANT#2, the received signals of the A system and the B system of the fifth to eighth transmission/reception modules (No. 5 to No. 8) are compared by the fifth to eighth EL comparators 3-35 to 3-38, and the comparison outputs are combined by the second 4-combiner 3-84 to obtain the ANT#2EL signal. In addition, the combined signal of the comparison outputs of the fifth and sixth EL comparators 3-35, 3-36 is compared with the combined signal of the comparison outputs of the seventh and eighth EL comparators 3-37, 3-38 by the second AZ comparator 3-A2 to obtain the ANT#2Σ signal and the ANT#2AZ signal.

Similarly, in the third antenna ANT#3, the A-system received signals and B-system received signals of the ninth to twelfth transmitting/receiving modules (No. 9 to No. 12) are compared by the ninth to twelfth EL comparators and combiners 3-39 to 3-312, and the comparison outputs are combined by the third 4-combiner 3-83 to obtain the ANT#3EL signal. In addition, the combined signal of the comparison outputs of the ninth and tenth EL comparators and combiners 3-39, 3-310 is compared with the combined signal of the comparison outputs of the eleventh and twelfth EL comparators and combiners 3-311, 3-312 by the third AZ comparator and combiner 3-A3 to obtain the ANT#3Σ signal and the ANT#3AZ signal.

Similarly, in the fourth antenna ANT#4, the A-system received signals and B-system received signals of the 13th to 16th transmission/reception modules (No. 13 to No. 16) are compared by the 13th to 16th EL comparators and combiners 3-313 to 3-316, and the comparison outputs are combined by the fourth combiner 3-84 to obtain the ANT#4EL signal. In addition, the combined signal of the comparison outputs of the 13th and 14th EL comparators and combiners 3-313, 3-314 is compared with the combined signal of the comparison outputs of the 15th and 16th EL comparators and combiners 3-315, 3-316 by the fourth AZ comparator and combiner 3-A4 to obtain the ANT#4Σ signal and the ANT#4AZ signal.

As described above, in the second embodiment, the antenna is divided into multiple groups, each of which functions as an independent electronically scanned antenna. In addition, there are four transmission inputs, and the transmission frequency of each antenna can be set independently, so problems due to radio interference do not occur. In addition, by providing independent comparators and combiners for one beam and multiple beams within the distribution/combination comparator 3 for the reception system output of the transmission/reception module, it is possible to change the frequency for each beam while maintaining the functionality and performance of a conventional single-beam electronically scanned antenna, making it possible to track multiple targets simultaneously.

The present invention is not limited to the above-described embodiment as it is, and in the implementation stage, the components can be modified and embodied without departing from the gist of the invention. In addition, various inventions can be formed by appropriately combining the multiple components disclosed in the above-described embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, components from different embodiments may be appropriately combined.

1...antenna element,
2: Transmitting and receiving modules (No. 1 to No. 16), 2-1 to 2-4: module units,
2-11: Phase shifter (PS), 2-12: TX/RX switch (SPDT), 2-13: Intermediate amplifier (MPA), 2-14: Driver (DRV), 2-15: Attenuator (ATT), 2-16: High-power amplifier (HPA), 2-17: Circulator (CIR), 2-18: Bandwidth limiting filter (BEF), 2-19: Limiter (LIM), 2-1A: Low-noise amplifier (LNA), 2-1B1, 2-1B2: RF switch (SPDT), 2-1C: Intermediate amplifier (MPA), 2-51, 2-52: 2-combiner,
2-1D...RF switch integrated 3-bit MMIC phase shifter, L1...line with 45 degree phase difference, L2...line with 90 degree phase difference, L3...line with 180 degree phase difference, SW11, SW12, SW21, SW12, SW31, SW12...RF switches,
3...Distributor/synthesizer comparator, 3-11 to 3-132...2 distributors (2 combiners), 3-21 to 3-216...2 combiners, 3-31 to 3-316...EL comparison combiner, 3-4...8 combiners, 3-41 to 3-416...circulator, 3-51, 3-52...4 combiners, 3-6...AZ comparison combiner, 3-7...8 distributor, 3-81 to 3-84...4 combiners, 3-91 to 3-98...2 combiners, 3-A1 to 3-A4...AZ comparison combiners, 3-B1 to 3-B4...4 distributor.

Claims (5)

a four-element integrated transceiver module that performs transmission and reception processing for each of the first and second antenna elements and the third and fourth antenna elements, outputs a first composite signal obtained by combining the received signals of the first and second antenna elements, and outputs a second composite signal obtained by combining the received signals of the third and fourth antenna elements;
a dividing/combining comparator for dividing/combining a first combined signal and a second combined signal output from the transmitting/receiving module to form a plurality of combined beams;
The distribution/combination comparator includes:
a first two-way distributor that divides a first composite signal obtained by the transmission/reception module into two;
a second two-way distributor that divides a second composite signal obtained by the transmission/reception module into two;
a first comparator using a 90° hybrid to which a first output of the first 2-way divider and a first output of the second 2-way divider are connected and which divides all antenna elements to form a plurality of beams;
a second comparator including a combiner and a 90° hybrid, the second output of which is connected to the second output of the first 2-way divider and which forms a composite beam of all antenna elements;
an electronically scanned antenna comprising a transmission signal supplying means for supplying a plurality of independent transmission signals, each having an arbitrary frequency for each beam, to the transmitting/receiving module; a first to an i-th (i is an integer of 2 or more) four-element integrated transceiver module that performs a transmission and reception process for each of the first and second antenna elements and the third and fourth antenna elements, outputs a first composite signal obtained by combining the reception signals of the first and second antenna elements, and outputs a second composite signal obtained by combining the reception signals of the third and fourth antenna elements;
a dividing/combining comparator for dividing/combining and comparing a first combined signal and a second combined signal outputted from each of the first to i-th transmission/reception modules to form a plurality of combined beams;
The distribution/combination comparator includes:
a first 2-way distributor group for distributing first composite signals output from the first to i-th transmission/reception modules into two, respectively;
a second 2-way distributor group that distributes second composite signals output from the first to i-th transmission/reception modules into two, respectively;
a first to an i-th 2-way combiner that combines a distribution output of the first 2-way divider group and a distribution output of the second 2-way divider group;
a first to an i-th EL comparison and synthesis unit using a 90° hybrid, which receives the synthesis outputs of the first to i-th two synthesis units, performs EL (elevation) comparison and synthesis, and outputs the comparison and synthesis results to two systems;
an EL combiner for combining outputs from one of the first to i-th EL comparison combiners to obtain an EL output;
an AZ comparison and synthesis unit which receives the other outputs of the first to i-th EL comparison and synthesis units, performs AZ (azimuth) comparison and synthesis, and obtains an AZ output from the comparison result;
a transmission signal supplying means for supplying a plurality of independent transmission signals having arbitrary frequencies for each beam to the first to i-th transmission/reception modules. a first to an i-th (i is an integer of 2 or more) four-element integrated transceiver module that performs a transmission and reception process for each of the first and second antenna elements and the third and fourth antenna elements, outputs a first composite signal obtained by combining the reception signals of the first and second antenna elements, and outputs a second composite signal obtained by combining the reception signals of the third and fourth antenna elements;
a dividing/combining comparator for dividing/combining and comparing a first combined signal and a second combined signal outputted from each of the first to i-th transmission/reception modules to form a plurality of combined beams;
The distribution/combination comparator includes:
a first 2-way distributor group for distributing first composite signals output from the first to i-th transmission/reception modules into two, respectively;
a second 2-way distributor group that distributes second composite signals output from the first to i-th transmission/reception modules into two, respectively;
a first to i-th EL comparison combiner using a 90° hybrid, which receives the distribution output of the first 2-way divider group and the distribution output of the second 2-way divider group, performs EL (elevation) comparison and combination, and outputs the comparison and combination result to two systems;
an EL combiner for combining outputs from one of the first to i-th EL comparison combiners to obtain an EL output;
a first through an i-th AZ comparison and synthesis unit which receives the other outputs of the first through i-th EL comparison and synthesis units and performs AZ (azimuth) comparison and synthesis;
an AZ combiner that combines the outputs of the first through i-th AZ comparison combiners to obtain an AZ output;
a transmission signal supplying means for supplying a plurality of independent transmission signals having arbitrary frequencies for each beam to the first to i-th transmission/reception modules. An electronically scanned antenna according to any one of claims 1 to 3, wherein the transceiver module incorporates an MMIC (monolithic microwave integrated circuit) that integrates an input RF switch and a digital phase shifter. a first composite signal and a second composite signal obtained by a four-element integrated transceiver module that performs transmission and reception processing for each of the first and second antenna elements and the third and fourth antenna elements, outputs a first composite signal obtained by combining the received signals of the first and second antenna elements, and outputs a second composite signal obtained by combining the received signals of the third and fourth antenna elements;
A signal processing method for an electronically scanned antenna, which distributes a first combined signal and a second combined signal obtained by the transmitting/receiving module into two, compares and combines one of the distributed outputs using a combiner and a 90° hybrid to form a combined beam of all antenna elements, and compares and combines the other distributed output using a combiner and a 90° hybrid to form multiple beams, and supplies multiple independent transmission signals with arbitrary frequencies for each beam to the transmitting/receiving module.

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