Reception antenna device, and transmission antenna device

Abstract

To provide a reception antenna device capable of reducing influences of a communication state of a communication signal, and a transmission antenna device.SOLUTION: A reception antenna device 1 comprises: an antenna section 2 in which a plurality of antenna units 3 for receiving n pieces of communication signals having different directivity is provided; a time division section 11 which is connected to the antenna section; and n pieces of signal reception sections 12 connected to the time division section and provided correspondingly to n pieces of reception signals for demodulating the n pieces of reception signals from the received communication signals. The time division section performs time division in a shorter sampling period than a period of a symbol in each of the n pieces of reception signals at the time of reception, switches a connection of the antenna section with the n pieces of signal reception sections in any connection timing in accordance with communication states of the reception signals, and samples the n pieces of reception signal on the directivity basis.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a receiving antenna device and a transmitting antenna device.

Background Art

[0002] In recent years, research on fifth-generation (5G) communication for realizing high-speed and high-capacity communication has been underway. So far, Massive MIMO communication, which further evolves MIMO (Multiple Input Multiple Output) communication enabling high-speed and high-capacity communication, has been realized. According to Massive MIMO communication, a radio base station can perform wireless communication with a number of mobile stations simultaneously by performing beamforming using a number of antennas.

[0003] In order to transmit a signal in the millimeter-wave band over a long distance, it is necessary to perform beamforming with directivity using a phased array antenna using a number of antennas. When attempting to realize Massive MIMO communication with a phased array antenna in the millimeter-wave band, it is necessary to configure circuits for the number of MIMO streams for each antenna (see Non-Patent Document 1, FIG. 15). Then, in a phased array antenna in which the number of antennas is large in Massive MIMO communication, it is necessary to configure circuits corresponding to the number of streams of communication targets for each antenna, and as the number of antennas increases, the circuit configuration becomes enormous, and there is a risk that power consumption and cost will increase significantly. The inventors have proposed a wireless communication device that can transmit and receive signals with a number of mobile stations while simplifying the circuit configuration (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In wireless communication, the communication signals transmitted and received are affected by communication conditions such as transmission and reception levels and interference waves, and the quality may deteriorate. In Patent Document 1, no technology regarding reducing the influence of communication conditions on communication signals has been proposed yet. As a result of continuous intensive research on wireless communication technology, the inventors have found a method for reducing the influence of communication conditions.

[0006] An object of the present invention is to provide a receiving antenna device and a transmitting antenna device capable of reducing the influence of communication conditions on communication signals.

Means for Solving the Problems

[0007] The present invention includes an antenna unit provided with a plurality of antenna units for receiving n communication signals having different directivities, a time-division unit connected to the antenna unit, and a signal reception unit provided corresponding to each of the n received signals for demodulating n received signals from the received communication signals, connected to the time-division unit. The time-division unit performs time-division at a sampling period shorter than the symbol period of each of the n received signals at the time of reception, and switches the connection between the antenna unit and the n signal reception units at an arbitrary connection timing according to the communication state of the received signal to sample the n received signals for each directivity. The antenna unit receives the divided reception signals obtained by dividing the communication signals corresponding to the directivity at the sampling period at the connection timing, and each signal reception unit acquires the divided reception signal corresponding to its own directivity at the connection timing of connecting to the time-division unit, and demodulates the received signal corresponding to its own directivity individually, which is a receiving antenna device.

Effects of the Invention

[0008] According to the present invention, the influence of communication conditions on communication signals can be reduced.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Embodiments for Carrying Out the Invention

[0010] As shown in FIG. 1, the wireless communication system S is composed of a receiving antenna device 1 and a plurality of mobile stations B. The wireless communication system S enables simultaneous communication between the receiving antenna device 1 and a plurality of mobile stations Bn (n is a natural number). The receiving antenna device 1 individually receives a plurality of communication signals Fn having directivity arriving from a plurality of mobile stations Bn using a phased array antenna. The receiving antenna device 1 demodulates a received signal based on the received communication signal Fn.

[0011] As shown in FIG. 2, the receiving antenna device 1 is configured as, for example, a full-digital phased array antenna applied to a wireless communication system S. The receiving antenna device 1 is applied to, for example, a base station of a mobile communication network, a base station such as a wireless LAN (Local Area Network), or an antenna device of an artificial satellite. The receiving antenna device 1 includes, for example, an antenna unit 2 provided with a plurality of antenna units 3 and a receiving unit 10 for receiving a communication signal for communication. The antenna unit 2 is a phased array antenna composed of m (m is a natural number) antenna units 3.

[0012] The antenna unit 2 receives, for example, millimeter-wave communication signals Fn transmitted from n mobile stations Bn. The antenna unit 2 adjusts the directivity of the communication signals transmitted from the positions of the respective mobile stations Bn and receives n communication signals Fn with different directivities. The antenna unit 2 includes a plurality of (for example, m) antenna units 3. The m antenna elements 4 are arranged in a matrix on a two-dimensional plane.

[0013] The plurality of antenna units 3 receive n communication signals with different directivities. The antenna unit 3 includes, for example, an antenna element 4 that receives the communication signal Fn between the antenna unit 3 and the mobile station Bn, an amplifier 5 connected to the antenna element 4, and a phase adjustment unit 6 connected to the amplifier 5. The amplifier 5 and the phase adjustment unit 6 constitute an RF phase shifter 7 that changes the phase of the radio frequency (RF) modulated wave itself. The connection relationship between the amplifier 5 and the phase adjustment unit 6 may be interchanged.

[0014] The antenna element 4 receives n mobile stations B and n communication signals Fn. That is, the antenna element 4 can communicate with n streams. The antenna element 4 is, for example, a patch antenna. Adjacent antenna elements 4 are arranged, for example, at intervals of half the wavelength of the received signal.

[0015] One amplifier 5 is provided, for example, corresponding to one antenna element 4. The amplifier 5 adjusts the gain (power) of the received signal. The amplifier 5 operates in conjunction with other circuits based on a clock signal described later. The amplifier 5 is formed, for example, in one circuit for reception.

[0016] One phase adjuster 6 is provided, for example, corresponding to one amplifier 5. A plurality of phase adjusters 6 are connected to the receiving unit 10. The phase adjuster 6 adjusts the phase of the received signal. The phase adjuster 6 operates in conjunction with other circuits based on a clock signal described later. In the antenna unit 2, the phases of the signals received with a phase difference in the plurality of antenna units 3 are individually adjusted, and the plurality of phase-adjusted signals are combined and output to the receiving unit 10. Thereby, the phase adjuster 6 can give directivity to the reception sensitivity of the received signal in accordance with the arrival direction of the communication signal transmitted from the mobile station B.

[0017] The receiving unit 10 includes, for example, a time-division unit 11 connected to the antenna unit 2 and n signal receiving units 12 connected to the time-division unit 11. The time-division unit 11 switches the connection between the antenna unit 2 and the n signal receiving units, for example, during reception. Details of the control content of the switching timing of the time-division unit 11 will be described later.

[0018] n signal receiving units 12 are provided corresponding to n communication signals Fn. The signal receiving unit 12 demodulates the communication signal Fn transmitted from the mobile station B into a received signal Yn.

[0019] The signal receiving unit 12, for example, decodes the received signal, performs AD conversion on the received signal, and converts the frequency of the communication signal including the received signal. The signal receiving unit 12 is configured, for example, according to the antenna device described in Patent Document 1.

[0020] The antenna unit 2 and the receiving unit 10 are connected to a global clock circuit C including a clock input unit C1 for inputting a control clock signal and a clock branching unit C2 for branching the clock signal. The clock input unit C1 receives a clock signal generated in another circuit. The clock branching unit C2 branches the clock signal input to the clock input unit C1 and inputs it to the antenna unit 2 and the receiving unit 10. A clock path CK serving as a transmission path for the clock signal is formed in the global clock circuit C. The clock path CK inputs the clock signal to each component provided in the antenna unit 2 and the receiving unit 10. The antenna unit 2 and the receiving unit 10 operate synchronously based on the clock signal input via the global clock circuit C. The clock signal is, for example, a rectangular wave signal with a frequency of 0.8 to 2.0 GHz. The frequency of the clock signal may be appropriately changed according to the communication state as described later.

[0021] FIG. 3 shows a specific circuit configuration of the receiving antenna device 1. In the illustrated example, the receiving antenna device 1 includes, for example, an antenna unit 2 and a receiving unit 10 connected to the antenna unit 2. The antenna unit 2 is provided with, for example, eight antenna units 3. The antenna unit 3 is provided with an antenna element 4-m and an RF phase shifter 7-m (m = 1 to 8). The antenna unit 3 receives, for example, four communication signals Fn with different directivities. The receiving unit 10 is provided with a time division unit 11 connected to the antenna unit 2 and four signal receiving units 12-n (n = 1 to 4).

[0022] Each RF phase shifter 7-m and the time division unit 11 are connected by a clock path CK for inputting a clock signal. The clock path CK is provided with a plurality of delay circuits G that give a delay time to the clock signals input to the antenna unit 2 and the reception unit 10 to synchronize them. The delay circuit G is constituted by, for example, a digital time conversion circuit (Digital-To-Time Converter: DTC). The delay circuit G compensates for the offset of the time difference generated in the clock signal input between the circuits of the antenna unit 2 and the reception unit 10, and inputs the clock signal to the RF phase shifter 7-m and the reception unit 10 simultaneously. When a code corresponding to the length of the delay time as a compensation value is input to the delay circuit G, the delay circuit G gives a delay time corresponding to the code to the clock signal and outputs it. The compensation value is adjusted in the delay circuit G at the time of circuit mounting.

[0023] The time division unit 11 is connected to the RF phase shifter 7-m via a signal path K. The time division unit 11 is provided with a switching unit 11A that connects each RF phase shifter 7-m and each signal reception unit 12-n. The switching unit 11A is constituted by, for example, four switch circuits 11An (n = 1 to 4). The four switch circuits 11An (n = 1 to 4) connect all the RF phase shifters 7-m and the corresponding signal reception units 12-n at the connection timing when they are in the on state, and output the reception signal Yn corresponding to the signal reception unit 12-n. For example, when receiving a communication signal F1, the switch circuit 11D1 becomes in the on state, the signal reception unit 12-1 and the antenna unit 2 are connected, and the reception signal Y1 is output from the signal reception unit 12-1.

[0024] The time division unit 11 is provided with a switch adjustment unit 11B connected to the switching unit 11A. The switch adjustment unit 11B is constituted by four switch adjustment circuits 11Bn (n = 1 to 4). The switch adjustment circuit 11Bn is configured to adjust the duty ratio and the delay time of the connection time of the switch circuit 11An.

[0025] The time division unit 11 is provided with a switch control unit 11C connected to the switch adjustment unit 11B. The switch control unit 11C individually controls the switch circuit 11An and the switch adjustment circuit 11Bn. The switch control unit 11C executes control to rank the connection timings for turning on the switch circuit 11An and the switch adjustment circuit 11Bn. When any of the switch circuits 11An is turned on, the switch control unit 11C connects to the switch adjustment circuit 11Bn at the connection timing.

[0026] The switch control unit 11C connects to the switch adjustment circuit 11Bn corresponding to the connection timing and turns on the switch circuit 11An. The switch adjustment circuit 11Bn adjusts the delay time for offsetting the on state of the switch circuit 11An at this time and the duty ratio of the on state. The switch control unit 11C is provided with, for example, a rewritable table for ranking the connection timings of the switch circuit 11An. The switch control unit 11C switches the switch circuit 11An to the on state at the connection timing based on the data in the table.

[0027] During the on state, the switch circuit 11An outputs the received signal received by the antenna unit 2 to the corresponding signal reception unit 12-n. At the connection timing, the switch control unit 11C controls the phase delay control unit 11D connected to the RF phase shifter 7-m to operate the RF phase shifter 7-m.

[0028] The phase delay control unit 11D is configured to perform SPI (Serial Peripheral Interface) communication with each RF phase shifter 7-m. The phase delay control unit 11D outputs a control signal synchronized with the switch control unit 11C to each RF phase shifter 7-m and operates the RF phase shifters 7-m in synchronization with the switch control unit 11C.

[0029] FIG. 4 shows the circuit configuration of the RF phase shifter 7-m. A control signal is input to the RF phase shifter 7-m from the phase delay control unit 11D. The RF phase shifter 7-m synchronizes with any one of the switch circuits 11An that is in the on state at the connection timing, and adjusts the phase delay amount of each signal receiving unit 12-n according to the directivity of the switch circuit 11An. Each RF phase shifter 7-m gives a phase delay amount to the communication signal (split reception signal described later) input at the connection timing and outputs it. The phase delay amount is adjusted according to the beam direction of the received signal and the arrangement position of the antenna element 4-m connected to the RF phase shifter 7-m.

[0030] With the above configuration, in each antenna element 4-m, received signals received at different timings are given different phase delay amounts in each RF phase shifter 7-m and output to the signal path K at the same time. By controlling so as to give a phase delay to each RF phase shifter 7-m, it is possible to improve the reception characteristics with respect to the arrival direction of the communication signal having directivity.

[0031] On the input side of the RF phase shifter 7-m, for example, a noise processing unit 7A is provided. The noise processing unit 7A is composed of an LNA (Low Noise Amplifier) circuit that removes broadband interference waves from the input signal and amplifies it. A phase adjustment unit 6 is connected to the downstream side of the noise processing unit 7A. An amplifier 5 is provided on the downstream side of the phase adjustment unit 6. The amplifier 5 is composed of a circuit such as a Variable Gain Amplifier (VGA), for example. As will be described later, since the gain of the received signal can be controlled based on the control of the switching unit 11A, the amplifier 5 may be omitted.

[0032] The phase adjustment unit 6 includes a phase adjustment circuit 6A that adjusts the phase delay amount and a phase adjustment control unit R that controls the phase adjustment circuit 6A. The phase adjustment circuit 6A is configured to realize phase delay by switching as will be described later.

[0033] The phase adjustment control unit R includes a retiming circuit 6B connected to the phase adjustment circuit 6A, a switch circuit unit 6C connected to the retiming circuit 6B, a phase adjustment control circuit 6E connected to the switch circuit unit, and a table 6D connected to the switch circuit unit 6C. The phase adjustment control circuit 6E operates in synchronization with the control signal output from the phase delay control unit 11D. The phase adjustment control circuit 6E is constituted by a logic circuit such as a state machine (Finite State Machine: FSM), for example.

[0034] Based on the content of the control signal, the phase adjustment control circuit 6E adjusts the amount of phase delay applied to the communication signal (split reception signal described later) at the connection timing. The phase adjustment control circuit 6E controls the switch circuit unit 6C in synchronization with the connection timing of the switch circuit 11An.

[0035] The switch circuit unit 6C operates based on the delay control signal output from the phase adjustment control circuit 6E. In the illustrated example, the switch circuit unit 6C is configured as a time-division unit that switches a plurality of connection destinations. For example, a plurality of switch circuits 6Cn are provided in the switch circuit unit 6C according to the directivity of the received signal. In the illustrated example, four (2-bit) switch circuits 6Cn are provided. One switch circuit 6Cn is provided in association with one switch circuit 11An.

[0036] The switch circuit 6Cn operates in synchronization with the connection timing of the switch circuit 11An. At the connection timing of the switch circuit 11An, the switch circuit 6Cn reads data from the table 6D. The table 6D is configured to be rewritable. The table 6D is constituted by, for example, a LUT (Lookup table) that records a data array for controlling the amount of phase delay of the phase adjustment circuit 6A at the connection timing.

[0037] Table 6D stores data for controlling the phase delay amount of the phase adjustment circuit 6A provided in the RF phase shifter 7-m to which it belongs. As will be described later, Table 6D stores directivity delay control signals for controlling as many switch circuits 6P as the phase adjustment circuit 6A to be controlled has. The directivity delay control signal stores data on which switch circuit 6P to execute what control at which reception timing. In the illustrated example, Table 6D stores 4×4 directivity delay control signals.

[0038] Table 6D may be provided redundantly. In that case, one table in Table 6D is used during control execution, and the other table is rewritten according to the reception state of interference waves during control execution. Therefore, the duplicated Table 6D may be used with the table to be used switched as appropriate.

[0039] The phase adjustment control circuit 6E operates the phase adjustment circuit 6A via the switch circuit 6Cn at the connection timing of the switch circuit 11An. The switch circuit section 6C outputs a directivity delay control signal at the timing according to the ranking data recorded in Table 6D at the connection timing. The phase adjustment circuit 6A adjusts the phase delay amount according to the directivity based on the directivity delay control signal and controls its reception timing.

[0040] In conjunction with the switch circuit section 6C, the retiming circuit 6B operates. The retiming circuit 6B is configured by combining register elements such as DFF (Delay Flip Flop). The retiming circuit 6B equalizes the distribution of the output timing of the directivity delay control signal output from Table 6D in conjunction with the switch circuit section 6C and outputs it to the phase adjustment circuit 6A. The switch circuit section 6C and the retiming circuit 6B cooperate to output a directivity delay control signal to the phase adjustment circuit 6A.

[0041] A clock path CK is connected to the switch circuit section 6C and the phase adjustment control circuit 6E. The switch circuit section 6C and the phase adjustment control circuit 6E operate in conjunction based on a clock signal input from the clock path CK.

[0042] With the above configuration, the phase adjustment unit 6 performs phase adjustment of the reception timing for receiving a signal (a divided reception signal described later) that is received in synchronization with the connection timing of the time division unit 11, and can quickly switch the directivity of the antenna unit 2.

[0043] FIGS. 5 and 6 show the circuit configuration of the phase adjustment circuit 6A. The phase adjustment circuit 6A is configured to weight and add two signals having orthogonal phases, and give a phase delay amount corresponding to the directivity of the signal in synchronization with the connection timing of the time division unit 11 and output the result. The phase adjustment circuit 6A includes, for example, a switch circuit section 6Z that performs phase adjustment of the reception timing for receiving a divided reception signal in synchronization with the connection timing of the time division unit 11 and switches the directivity of the antenna unit 2.

[0044] The switch circuit section 6Z is composed of a first switch circuit section 6X branched from a signal input section 6V and a second switch circuit section 6Y. The signal input section 6V branches a signal input on the input side of the phase adjustment circuit 6A into two systems of first branch signals and a second branch signal. The signal input section 6V outputs the first branch signal and outputs the second branch signal with a 90-degree phase delay with respect to the first branch signal. The first branch signal is input to the first switch circuit section 6X. The second branch signal is input to the second switch circuit section 6Y.

[0045] The first switch circuit section 6X is configured to adjust and output the gain of the first branch signal. The second switch circuit section 6Y is configured to adjust and output the gain of the second branch signal. The first output signal output from the first switch circuit section 6X and the second output signal output from the second switch circuit section 6Y are combined on the output section 6W side of the phase adjustment circuit 6A and output as an output signal (a divided reception signal described later).

[0046] The first switch circuit section 6X is a vector summing type circuit including a plurality of switch circuits 6P. In the illustrated example, the first switch circuit section 6X includes four switch circuits P. Each switch circuit 6P is controlled to be in an on state (Fig. 6: Code = 1) and an off state (Fig. 6: Code = 0) according to the content of the directivity delay control signal output from the phase adjustment control section R. Different weighting parameters are individually set for each switch circuit P according to a desired phase delay amount. Each switch circuit P outputs an output value with its gain adjusted in the on state.

[0047] The second switch circuit section 6Y is a vector summing type circuit including a plurality of switch circuits 6P. In the illustrated example, the second switch circuit section 6Y includes four switch circuits P. Each switch circuit 6P is controlled to be in an on state (Fig. 6: Code = 1) and an off state (Fig. 6: Code = 0) according to the content of the directivity delay control signal output from the phase adjustment control section R. Different weighting parameters are individually set for each switch circuit P according to a desired phase delay amount. The weighting parameters are set according to fluctuations in the impedance of the circuit calculated in the circuit design.

[0048] Each switch circuit P outputs an output value with its gain adjusted in the on state. The weighting parameters set for each switch circuit P of the first switch circuit section 6X and the second switch circuit section 6Y are adjusted to 1 times, 2.8 times, 4 times, 17 times, as compared with the weighting parameters set in binary format such as 1 time, 2 times, 4 times, 8 times, etc. The weighting parameters set to 1 times, 2.8 times, 4 times, 17 times may be adjusted in the range of -30% to +30% according to the device configuration.

[0049] Based on the content of the directivity delay control signal, the phase adjustment control unit R combines the switch circuit P that is turned on / off in the first switch circuit unit 6X and the switch circuit P that is turned on / off in the second switch circuit unit 6Y, and gives a desired phase delay to the output signal for output. The phase adjustment control unit R turns on any one of the switch circuits P from the first switch circuit unit 6X, or turns off all the switch circuits P. At the same time, the phase adjustment control unit R turns on any one of the switch circuits P from the second switch circuit unit 6Y, or turns off all the switch circuits P based on the content of the directivity delay control signal.

[0050] With the above configuration, the plurality of switch circuits P provided in the phase adjustment circuit 6A input two orthogonal signals having orthogonal phases divided from the received signal, weight them according to the directivity with respect to the orthogonal signals, and add the two weighted signals to give a phase difference to the signal for output.

[0051] With the above configuration, according to the phase adjustment circuit 6A, an output signal given a desired phase delay is output from the output unit 6W. With the above configuration, the phase adjustment circuit 6A can quickly switch the control of giving a desired phase delay to the output signal with respect to the input signal.

[0052] Hereinafter, the operation of the receiving antenna device 1 will be described. The receiving antenna device 1 is communicating with, for example, n mobile stations B at the same time. First, the operation of the receiving antenna device 1 receiving a received signal from n mobile stations B will be described.

[0053] As shown in FIG. 7, for example, one symbol Pn of each of the n received signals arrives at the antenna unit 2. In the illustrated example, there are 4 mobile stations and 4 communication signals Fn. The communication signals Fn arrive in 4 arrival directions φn. One symbol Pn is a signal indicating 0 or 1 set based on a predetermined modulation method. The period (T0) of one symbol Pn is shorter than the period (TS) of a time slot of a predetermined unit.

[0054] At the time of reception, the antenna unit 2 receives the symbol Pn of the received signal by time-division at the sampling period (Δt) of a time slot shorter than the period (T0) of each of the n received signals Pn at the connection timing of the time-division unit 11 as described later. In the illustrated example, the connection timing is set so as to receive the symbol Pn in the order in which the angle of the arrival direction of the communication signal Fn increases (decreases).

[0055] The sampling period is set to Δt having a time length slightly shorter than, for example, 1 / n×T0. By performing overlap clock control, the sampling period can prevent overlap between the divided received signals in sampling (see Patent Document 1). Also, the sampling period may be made longer for an azimuth in which the received power of the received signal is weak. That is, the sampling period may adjust the time length in inverse proportion to the intensity of the received power. In the illustrated example, the sampling period is set to approximately 1 / 4×T0, which is shorter than the period of the symbol Pn, for example. The sampling period is set, for example, by being assigned to different communication signals Fn. The sampling period may be set to other periods.

[0056] In the illustrated example, the divided transmission signal D1 obtained by time-dividing and receiving the symbol P1 in the first time slot is received. The divided transmission signal D2 obtained by time-dividing and receiving the symbol P2 in the second time slot is received. The divided transmission signal D3 obtained by time-dividing and receiving the symbol P3 in the third time slot is received. The divided transmission signal D4 obtained by time-dividing and receiving the symbol P4 in the fourth time slot is received. In the illustrated example, the time-division unit 11 samples the divided received signal Dn at the first sampling frequency f1.

[0057] In each antenna unit 3, during reception, the phase delay amount is adjusted in the phase adjustment circuit 6A, and the directivity is adjusted so as to increase the reception sensitivity with respect to the arrival directions of the n received signals. The adjustment of the directivity may be performed stepwise and periodically, for example, at predetermined angles such as 30°. The directivity may be adjusted not only in two-dimensional directions but also in three-dimensional directions. In the illustrated example, in the antenna unit 2, in order to adjust the directivity to the four arrival directions φn of the received signals, the phase delay amount is adjusted in the phase adjustment circuit 6A in each antenna unit 3.

[0058] In each antenna unit 3, when the divided reception signal is received, the power (gain) of the divided reception signal is quadrupled by the amplifier 5 according to the sampling period, and the amplified divided reception signals D´1-4 are obtained. The amplification amount of the divided reception signal Dn may be adjusted according to the magnitude of the power obtained when the divided reception signal is detected. The time division unit 11 may adjust the length of the sampling period at the connection timing according to the reception state of the interfering wave with respect to the received signal.

[0059] The time division unit 11 may adjust the sampling period when sampling the received signal according to the reception state of the interfering wave with respect to the received signal, and adjust the reception level of the divided reception signal to be within a predetermined level range. The time division unit 11 adjusts so as to shorten the sampling period as the intensity of the reception level of the received signal increases. The time division unit 11 adjusts so as to lengthen the sampling period as the intensity of the reception level of the received signal decreases.

[0060] The time-division unit 11 operates in conjunction with the antenna unit 2. The time-division unit 11 performs time-division at a sampling period shorter than the period of each symbol of the n received signals, and switches the connection between the antenna unit 2 and the n signal reception units 12. Since the antenna unit 2 sequentially receives received signals corresponding to the directivities at the switching timing of the time-division unit 11, it is not necessary to provide a circuit configuration in a number corresponding to the number of streams. At the switching timing of the time-division unit 11, n divided received signals Dn corresponding to the directivities of the n received signals are received in the antenna unit 2. The divided received signal Dn has its power amplified n times by the amplifier 5 to generate a divided received signal D'n. The divided received signal D'n is sequentially input to the signal reception unit 12 and sampled.

[0061] Each signal reception unit 12 sequentially acquires a divided received signal D'n corresponding to its own directivity at the connection timing with the time-division unit 11. Each signal reception unit 12 acquires a plurality of divided received signals during a predetermined time. Each signal reception unit 12 individually demodulates the received signal based on the plurality of acquired divided received signals. Each signal reception unit 12 can remove received signals having other directivities based on the S / N ratio of the received signal set according to the directivity, and recognize the divided received signal according to the directivity. Based on the above processing, n received signals are demodulated by the plurality of signal reception units 12.

[0062] As shown in FIG. 8, the first sampling frequency f1 may be changed. When noise increases due to the presence of interference waves for at least one symbol Pn among the plurality of symbols Pn, in order to shorten the sampling period, it may be changed to a sampling frequency higher than the first sampling frequency. The time-division unit 11 may be changed to a second sampling frequency f2 higher than the first sampling frequency f1 based on a clock signal CLK changed to twice the frequency, for example, according to the reception state of the interference wave with respect to the symbol Pn of the received signal. The time-division unit may sample the divided received signal D'n based on the second sampling frequency f2. In this case, the phase delay amount is also adjusted in the phase adjustment circuit 6A in each antenna unit 3 in conjunction with the time-division unit 11.

[0063] As shown in FIG. 9, within the period (T0) of one symbol Pn, the ranking for sampling the symbol Pn may be changed. When the sampling order of the symbol Pn is fixed based on the first sampling frequency f1 within the period (T0) of one symbol Pn, it may be more susceptible to the influence of interference waves. For example, when the absolute value of the difference between the band F1 of the symbol Pn and the band F2 of the interference wave is close to the first sampling frequency f1, it is more susceptible to the influence of the interference wave.

[0064] That is, when |F1 - F2| = f1 is satisfied, a beat occurs between the symbol Pn and the interference wave, and the interference wave is superimposed on the symbol Pn according to the period of the first sampling frequency f1. For example, when the first sampling frequency f1 is 1 GHz, the band of the symbol Pn is 28 GHz, and the band of the interference wave is 29 GHz or 27 GHz, the interference wave is superimposed on the symbol Pn according to the period of the first sampling frequency f1.

[0065] In this case, the time division unit 11 may switch the connection between the antenna unit 2 and the n signal reception units 12 at an arbitrary connection timing according to the communication state of the symbol Pn of the received signal, and sample the n received signals for each symbol Pn directivity. The time division unit 11 may sample the divided reception signal D'n based on the connection timing randomly ranked in the sampling period.

[0066] In this case, the antenna unit 2 receives, in conjunction with the time division unit 11, the divided reception signal D'n corresponding to the directivity at the sampling period at the changed connection timing. The signal reception unit 12-n acquires the divided reception signal D'n corresponding to its own directivity at the changed connection timing, and demodulates the reception signal corresponding to its own directivity individually. The time division unit 11 may perform amplitude compensation for adjusting the variation in the amplitude of the divided reception signal sampled based on the randomly ranked connection timings. When the time division unit 11 continuously samples the same divided reception signal D'n between adjacent time slots at the randomly ranked connection timings, the sampling periods may be made continuous.

[0067] As shown in FIG. 10, the above-described antenna unit 2 and reception unit 10 include a control unit 20 and a storage unit 22 that stores data and programs used in the control. The control unit 20 integrally controls the antenna unit 2 and the reception unit 10, for example, based on the data and programs stored in the storage unit 22, and executes processes related to transmission and reception.

[0068] The control unit 20 is realized, for example, by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of these components may be realized by hardware (including circuitry) such as LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), GPU (Graphics Processing Unit), or may be realized by the cooperation of software and hardware. The program may be stored in a storage device such as an HDD (Hard Disk Drive) or a flash memory that the storage unit 22 has in advance, or may be stored in a removable storage medium such as a DVD or a CD-ROM, and may be installed by mounting the storage medium on a drive device. Also, the program is not necessarily required, and a predetermined operation may be executed by configuring a sequential circuit in the control unit 20.

[0069] Hereinafter, each step of the processing of the wireless communication method executed in the receiving antenna device 1 will be described.

[0070] As shown in FIG. 11, the reception processing of the receiving antenna device 1 first detects n reception signals with different directivities in the antenna unit 2 (step S10). The time division unit 11 time-divides at a sampling period shorter than the symbol period of each reception signal based on the switching timing, and switches the connection between the antenna unit and the n signal reception units at an arbitrary connection timing according to the communication state of the reception signals, and samples the n reception signals for each directivity (step S12).

[0071] The antenna unit 2 receives the divided reception signals at the connection timing in the sampling period (step S14). Each signal reception unit 12-n acquires the divided reception signals corresponding to its own directivity at the connection timing for connecting to the time division unit 11, and individually demodulates the reception signals corresponding to its own directivity (step S16).

[0072] As described above, according to the reception antenna device 1, by time-division multiplexing and sampling n reception signals with different directivities at high speed, n reception signals can be demodulated substantially simultaneously. According to the reception antenna device 1, by time-division multiplexing n transmission signals with different directivities at high speed and sampling them at an arbitrary timing, n transmission signals can be transmitted substantially simultaneously while reducing the influence of interference waves.

[0073] According to the reception antenna device 1, by providing a plurality of switch circuits for phase adjustment that are interlocked with the time division unit 11 in the phase adjustment unit, the phase adjustment can be switched at high speed. According to the reception antenna device 1, since the divided reception signals are sampled at a random connection timing in the sampling period, the SNR of the reception signals of the entire device can be reduced. According to the reception antenna device 1, by changing the sampling frequency for sampling the divided reception signals, the influence of interference waves can be reduced.

[0074] [Modification Example 1] Hereinafter, modification examples will be described. In the following description, for the same configurations as those in the above-described embodiment, the same names will be used, and redundant descriptions will be omitted as appropriate. The above-described reception antenna device 1 can be configured as a transmission antenna device 100 by changing its configuration for transmission use.

[0075] As shown in FIG. 12, the transmission antenna device 100 is configured to transmit a transmission signal Hn to a plurality of mobile stations Bn. The transmission antenna device 100 includes, for example, an antenna unit 200 provided with a plurality of antenna units 300, and a transmission unit 1000 for transmitting a communication signal for communication. The antenna unit 200 is a phased array antenna composed of m (m is a natural number) antenna units 300.

[0076] The transmission unit 1000 includes n signal generation units 1200 that generate n transmission signals with different directivities. A time division unit 1100 is connected to the signal generation unit 1200. The time division unit 1100 is connected to an antenna unit 200 provided with m antenna units 300 for transmitting a transmission signal. An antenna element 4 is provided in the antenna unit 300. An amplifier 500 is connected to the antenna element 4. A phase adjustment unit 600 is connected to the amplifier 500.

[0077] As shown in FIG. 12, the time division unit 1100 switches the connection between the antenna unit 200 and the n signal transmission units, for example, during transmission. During transmission, the time division unit 1100 performs time division at a sampling period shorter than the symbol period of each of the n transmission signals Zn, and connects to each signal generation unit 1200 at an arbitrary connection timing. At the connection timing, the time division unit 1100 samples a divided transmission signal obtained by dividing a symbol of a communication signal corresponding to the directivity in the sampling period, and outputs the signal to the antenna unit 200.

[0078] At the connection timing when connected to the time division unit 1100, the antenna unit 300 acquires a divided reception signal corresponding to its own directivity, and gives a phase delay to the divided transmission signal corresponding to its own directivity. The antenna unit 200 transmits the n transmission signals Hn with directivity by transmitting the divided transmission signals with a phase difference given from a plurality of antenna elements 400.

[0079] As described above, according to the transmission antenna device 100, by time-division multiplexing and sampling at high speed n transmission signals with different directivities, n transmission signals can be transmitted substantially simultaneously. According to the transmission antenna device 100, by time-division multiplexing at high speed n transmission signals with different directivities and sampling them at an arbitrary timing, it is possible to transmit n transmission signals substantially simultaneously while reducing the influence of interference waves.

[0080] According to the transmission antenna device 100, by providing a plurality of switch circuits that perform phase adjustment in conjunction with the time division unit 1100 in the phase adjustment unit, the phase adjustment can be switched at high speed. According to the transmission antenna device 100, since the divided transmission signals are sampled at a random connection timing in the sampling period, the SNR of the transmission signals of the entire device can be reduced. According to the transmission antenna device 100, by changing the sampling frequency for sampling the divided transmission signals, the influence of interference waves can be reduced.

[0081] Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and its equivalent scope. Also, each configuration shown in the receiving antenna and the transmitting antenna illustrated in the embodiments and each modification example may be appropriately replaced, changed, or added. For example, the configurations shown in the receiving antenna device 1 and the transmitting antenna device 100 may be applied to the mobile station Bn side. The receiving antenna device 1 and the transmitting antenna device 100 may be configured as one device as a transceiver antenna. The transceiver antenna configured in this way may be applied to the mobile station Bn side.

Description of Reference Numerals

[0082] 1 Receiver antenna device, 2 Antenna section, 3 Antenna unit, 4 Antenna element, 5 Amplifier, 6 Phase adjustment section, 6A Phase adjustment circuit, 6B Retiming circuit, 6C Switch circuit section, 6D Table, 6E Phase adjustment control circuit, 6P Switch circuit, 6V Signal input section, 6W Output section, 6X First switch circuit section, 6Y Second switch circuit section, 6Z Switch circuit section, 7 RF phase shifter, 7A Noise processing section, 7-m RF phase shifter, 10 Receiver section, 11 Time division section, 11A Switching section, 11An Switch circuit, 11B Switch adjustment section, 11Bn Switch adjustment circuit, 11C Switch control section, 11D Phase delay control section, 11D1 Switch circuit, 12 Signal reception section, 20 Control section, 22 Memory section, 100 Transmitter antenna device, 200 Antenna section, 300 Antenna unit, 400 Antenna element, 500 Amplifier, 600 Phase adjustment section, 1000 Transmitter section, 1100 Time division section, 1200 Signal generation section, C Global clock circuit, C1 Clock input section, C2 Clock branching section, CK Clock path, CLK Clock signal, D Divided reception signal, Fn Communication signal, G Delay circuit, Hn Transmission signal, K Signal path, P Switch circuit, R Phase adjustment control section, S Wireless communication system

Claims

1. An antenna unit provided with a plurality of antenna units that receive n communication signals with different directivities, A time-division unit connected to the antenna unit, Connected to the time-division unit, and n signal reception units provided corresponding to each of the n received signals that demodulate the n received signals from the received communication signals, comprising: The time-division unit performs time-division at a sampling period shorter than the symbol period of each of the n received signals at the time of reception, and according to the communication state of the received signal, switches the connection between the antenna unit and the n signal reception units at an arbitrary connection timing to sample the n received signals for each directivity. The antenna unit receives the divided reception signal obtained by dividing the communication signal corresponding to the directivity at the sampling period at the connection timing. Each signal reception unit acquires the divided reception signal corresponding to its own directivity at the connection timing of connecting to the time-division unit, and individually demodulates the received signal corresponding to its own directivity. A receiving antenna device.

2. The time-division unit samples the divided reception signal based on the connection timing randomly ranked at the sampling period. The receiving antenna device according to claim 1.

3. The time-division unit Adjusts the order of the connection timing according to the communication state of the received signal. The receiving antenna device according to claim 1.

4. The time-division unit Adjusts the length of the sampling period at the connection timing according to the reception state of the interfering wave with respect to the received signal. The receiving antenna device according to claim 1.

5. The time-division unit Adjusts the sampling period when sampling the received signal according to the reception state of the interfering wave with respect to the received signal, and adjusts the reception level of the divided reception signal. The receiving antenna device according to claim 3.

6. The time-division unit Changes to a second sampling frequency higher than the first sampling frequency at which the divided reception signal is sampled in the symbol period according to the reception state of the interfering wave with respect to the received signal. Based on the second sampling frequency, samples the divided reception signal. The receiving antenna device according to claim 1.

7. Each of the antenna units is provided with a phase adjustment unit that individually performs phase adjustment of the timing for receiving the divided reception signal in synchronization with the connection timing of the time division unit. Each of the phase adjustment units performs phase adjustment of the reception timing for receiving the divided reception signal in synchronization with the connection timing of the time division unit, and includes a switch circuit unit that switches the directivity of the antenna unit. The reception antenna device according to claim 2.

8. Each of the phase adjustment units performs phase adjustment of the reception timing based on a rewritable table according to the connection timing of the time division unit and based on the random connection timing with the order changed. The reception antenna device according to claim 7.

9. The phase adjustment unit inputs two orthogonal signals having orthogonal phases divided from the divided reception signal, weights each of the orthogonal signals according to the directivity, and adds the two weighted divided reception signals to give a phase difference to the divided reception signal and outputs it, and includes a plurality of switch circuits. The reception antenna device according to claim 7.

10. The time division unit performs amplitude compensation for adjusting the variation in the amplitude of the divided reception signal sampled based on the randomly ranked connection timing. The reception antenna device according to claim 7.

11. The antenna unit, the time division unit, and the n signal reception units operate synchronously based on a clock signal input at the same timing. The reception antenna device according to claim 1.

12. n signal generation units that individually generate n communication signals, a time division unit connected to the n signal generation units, and a plurality of antenna units connected to the time division unit are provided, and an antenna unit that gives different directivities to the n communication signals and transmits them individually is provided. The time division unit performs time division at a sampling period shorter than the period of each symbol of the n transmission signals included in the communication signal during transmission. The connection between the antenna unit and the n signal generation units is switched at an arbitrary connection timing to sample the n transmission signals, and the n divided transmission signals obtained by dividing the transmission signals are output to the antenna unit. The antenna unit applies a phase difference corresponding to the directivity to each of the divided transmission signals at the connection timing in the sampling period, and transmits the n divided transmission signals according to the directivity. Transmitting antenna device.

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