Wireless communication system, wireless communication device, and beam pattern determination method

1. A wireless communication system comprising a wireless transmission device and a wireless reception device, wherein

the wireless reception device includes:

a plurality of reception antennas; and

a processor connected to the reception antennas, wherein

the processor executes a process including:

selecting transmission beam candidates or reception beam candidates based on a reception power of a signal transmitted by using transmission beams of a first array or of a signal received by using reception beams of the first array, the first array setting a delay difference between a plurality of antennas; and

determining a beam pattern of a transmission beam and a reception beam based on a reception power of a signal transmitted by using transmission beam candidates formed by a second array or of a signal received by using reception beam candidates formed by the second array, the second array setting a phase difference between a plurality of antennas.

2. The wireless communication system according to claim 1 , wherein

the selecting includes:

calculating reception powers of each of unit frequencies of the signal transmitted by using the transmission beams of the first array;

selecting a predetermined number of the unit frequencies in a descending order of the calculated reception powers; and

selecting the transmission beams in directions corresponding to the selected unit frequencies as the transmission beam candidates.

3. The wireless communication system according to claim 1 , wherein

the selecting includes selecting the transmission beam candidates based on the reception power of the signal transmitted by using the transmission beams of the first array, and

the determining includes:

receiving the signal transmitted from the wireless transmission device by using the reception beams of the first array;

selecting the reception beam candidates based on the reception power of the received signal;

receiving, by using the reception beam candidates formed by the second array, the signal transmitted by using the transmission beam candidates formed by the second array; and

determining the beam pattern based on the reception power of the received signal.

4. The wireless communication system according to claim 3 , wherein the determining the beam pattern includes determining, as a final transmission beam and a final reception beam, a combination of a transmission beam candidate and a reception beam candidate with which the reception power becomes maximum.

5. The wireless communication system according to claim 1 , wherein

the selecting includes selecting the transmission beam candidates based on the reception power of the signal transmitted by using the transmission beams of the first array, and

the determining includes:

receiving, by using the reception beams of the first array, the signal transmitted by using the transmission beam candidates formed by the second array; and

determining the beam pattern based on the reception power of the received signal.

6. The wireless communication system according to claim 5 , wherein the determining includes:

calculating the reception power of each of unit frequencies of the received signal; and

determining, as a final transmission beam and a final reception beam, a combination of a transmission beam candidate with which the reception power becomes maximum and a reception beam in a direction corresponding to a unit frequency with the maximum reception power.

7. A wireless communication device comprising:

a plurality of reception antennas; and

a processor connected to the reception antennas, wherein

the processor executes a process including:

selecting transmission beam candidates or reception beam candidates based on a reception power of a signal transmitted by using transmission beams of a first array or of a signal received by using reception beams of the first array, the first array setting a delay difference between a plurality of antennas; and

determining a beam pattern of a transmission beam and a reception beam based on a reception power of a signal transmitted by using transmission beam candidates formed by a second array or of a signal received by using reception beam candidates formed by the second array, the second array setting a phase difference between a plurality of antennas.

8. A beam pattern determination method comprising:

by a wireless reception device, forming a reception beam of a first array that sets a delay difference between a plurality of antennas;

by a wireless transmission device, forming transmission beam candidates by a second array that sets a phase difference between a plurality of antennas;

by the wireless reception device, receiving, by using the reception beam of the first array, a signal transmitted by using the transmission beam candidates formed by the second array; and

by the wireless reception device, determining a beam pattern of a transmission beam and a reception beam based on a reception power of the received signal.

9. A beam pattern determination method comprising:

by a wireless transmission device, forming a transmission beam of a first array that sets a delay difference between a plurality of antennas;

by a wireless reception device, forming reception beam candidates by a second array that sets a phase difference between a plurality of antennas;

by the wireless reception device, receiving, by using the reception beam candidates formed by the second array, a signal transmitted by the transmission beam of the first array; and

by the wireless reception device, determining a beam pattern of a transmission beam and a reception beam based on a reception power of the received signal.