Antenna beam scan module, and communication apparatus using the same

Patent metadata

Field	Value
Publication number	US-9620865-B2
Application number	US-201313765119-A
Country	US
Kind code	B2
Filing date	Feb 12, 2013
Priority date	Feb 20, 2012
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

Signals are maintained to be in phase at beam input ports of a Rotman lens antenna, and thus scanning at non-step antenna beam angles can be realized without increasing the number of input beams. The present invention provides an antenna beam scan module including: a Rotman lens that has plural beam ports and plural antenna ports; plural antenna elements; relative phase detectors that detect a relative phase difference between the signals input to the adjacent beam ports; phase shifters that offset the relative phase difference between the signals supplied to the adjacent beam ports on the basis of the relative phase difference detected by the relative phase detectors; and switches that select routes of the signals supplied to the beam ports through variable amplifiers, wherein the phase shifters are arranged on alternate routes through which the signals are supplied to the plural beam ports.

First claim

What is claimed is:

1. An antenna beam scan module comprising:
a Rotman lens that has a plurality of beam ports and a plurality of antenna ports and distributes and combines electric power of signals input and output to the antenna ports;
a plurality of antenna elements that input and output radio waves to the antenna ports;
a plurality of variable amplifiers that modulate magnitudes of the signals input to the beam ports;
a plurality of relative phase detectors that detect a plurality of relative phase differences between the signals input to the adjacent beam ports;
a plurality of phase shifters that offset the relative phase differences between the signals supplied to the adjacent beam ports on the basis of the relative phase differences detected by the relative phase detectors; and
a plurality of switches that select routes of the signals supplied to the beam ports through the variable amplifiers,
wherein the phase shifters are arranged on alternate routes through which the signals are supplied to the plurality of beam ports.

2. The antenna beam scan module according to claim 1 , further comprising:
a beam scan controller configured to independently control the switches and the variable amplifiers based on input antenna angle information.

3. The antenna beam scan module according to claim 2 ,
wherein a table of data related to phase fluctuations caused in accordance with the magnitude controlled by the variable amplifiers is stored in the beam scan controller to control the offset values of the phase shifters on the basis of the table, and the offset values are amended using the relative phase differences between the signals that are detected by the relative phase detectors and are input to the adjacent beam ports.

4. The antenna beam scan module according to claim 2 ,
wherein the relative phase detectors that detect the relative phase differences between the signals input to the adjacent beam ports are on the output side of the variable amplifiers, and
the beam scan controller is configured to output a plurality of control signals for adjusting the relative phase differences between the signals of the adjacent beam ports to the phase shifters on the basis of the relative phase differences detected by the relative phase detectors.

5. The antenna beam scan module according to claim 4 ,
wherein the relative phase detectors detect a plurality of magnitude differences in addition to the relative phase differences between the signals input to the adjacent beam ports, and
the beam scan controller is configured to output the control signals for adjusting the relative magnitude differences between the signals of the adjacent beam ports to the variable amplifiers on the basis of the detected magnitude differences.

6. The antenna beam scan module according to claim 5 ,
wherein the relative phase detectors that detect the relative phase differences between the signals input to the beam ports are configured using one I/Q mixer and two single mixers, the respective relative phase difference between two signals is detected on the basis of the magnitude ratio of a signal I: cos (phase difference) to a signal Q: sin (phase difference) obtained by mixing the adjacent signals with the I/Q mixer, and the magnitudes of the signals are calculated by the single mixers to obtain the magnitude ratio of two signals.

7. The antenna beam scan module according to claim 2 ,
wherein the phase shifters are provided on the output side of the variable amplifiers,
the relative phase detectors detect the relative phase differences between the signals input to the adjacent beam ports on the output side of the phase shifters, and
the beam scan controller is configured to output the control signals for adjusting the relative phase differences between the signals of the adjacent beam ports to the phase shifters on the basis of the relative phase differences detected by the relative phase detectors.

8. The antenna beam scan module according to claim 2 ,
wherein the beam scan controller is configured to store propagation phase data of the beam ports of the Rotman lens to amend the phase differences between the signals obtained by the relative phase detectors, and the offset values of the phase shifters are adjusted.

9. The antenna beam scan module according to claim 1 ,
wherein, on respective routes of the signals supplied to the beam ports for which no phase shifters are arranged, there is provided a transmission path having intermediate phase components in a range of fluctuations in passing phases of the phase shifters.

10. The antenna beam scan module according to claim 1 ,
wherein the relative phase detectors that detect the relative phase differences between the signals input to the beam ports are configured using I/Q mixers and the respective relative phase difference between two signals is detected on the basis of the magnitude ratio of a signal I: cos (phase difference) to a signal Q: sin (phase difference) obtained by mixing adjacent signals.

11. An antenna beam scan module comprising:
a Rotman lens that has a plurality of beam ports and a plurality of antenna ports and distributes and combines electric power of signals input and output to the antenna ports;
a plurality of antenna elements that input and output radio waves to the antenna ports;
a plurality of variable amplifiers that modulate magnitudes of the signals supplied from the beam ports;
a plurality of relative phase detectors that are arranged before and after the variable amplifiers to detect fluctuations in relative phase differences between the adjacent signals before and after the variable amplifiers;
a plurality of phase shifters that offset the fluctuations in relative phase differences between the adjacent signals caused by the magnitude control on the basis of the fluctuations in relative phase differences detected by the relative phase detectors; and
a plurality of switches that select routes of the signals supplied from the beam ports through the variable amplifiers,
wherein the phase shifters are arranged on alternate routes through which the signals are supplied from the plurality of beam ports.

12. A communication apparatus using the antenna beam scan module according to claim 1 .

13. The communication apparatus according to claim 12 comprising:
an antenna beam scan controller that is configured to control the antenna beam scan module;
a microwave band/milliwave band transceiver that modulates or demodulates RF signals input and output from the antenna beam scan module;
an analog/digital converter that converts an analog signal and a digital signal in transmission and reception of signals to/from the transceiver;
a signal processing circuit that processes digitalized communication signals; and
an input/output terminal through which an external digital device is connected,
wherein the antenna beam scan controller is configured to control antenna beam scanning of the antenna beam scan module based on an evaluation result of communication quality obtained from the signal processing circuit.

14. The communication apparatus according to claim 13 ,
wherein a microwave-band transmission/reception antenna is provided for the microwave band/milliwave band transceiver.

Assignees

• Hitachi Chemical Co Ltd

Inventors

• Nagaishi Hideyuki
• Miyazaki Masayuki
• Shimayama Yuichi

Classifications

• H01Q21/0031 Primary

  Parallel-plate fed arrays; Lens-fed arrays (multibeam arrays H01Q25/008) · CPC title

• H01Q3/2658

  Phased-array fed focussing structure · CPC title

• H01Q3/46

  Active lenses or reflecting arrays · CPC title

• H01Q3/40

  with phasing matrix · CPC title

• H01Q3/24

  varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching · CPC title