CN106411373A - Antenna array and method for base station to transmit signal - Google Patents

Abstract

The present invention provides an antenna array and a method for transmitting a signal by a base station, wherein the method for transmitting a signal by a base station includes: sharing physical downlink of a transmission mode using a cell-specific reference signal CRS for data demodulation transmitted by a high-power transceiver channel channel PDSCH and/or public control signals, perform beamforming and transmission of broadcast beams; The transceiver channel and the standard power transceiver channel are jointly used for sending service data. The invention reduces the weight loss of the base station and at the same time expands the broadcast coverage of the base station.

Description

An antenna array and a method for transmitting signals by a base station

technical field

The invention relates to the field of communication, in particular to an antenna array and a method for transmitting signals by a base station.

Background technique

Large-scale antenna technology is one of the key technologies for LTE-A evolution and future 5G. At present, an important topic of RAN1 in 3GPPR13 "Study on Elevation Beam forming/Full-Dimension (FD) MIMO for LTE" mainly studies multiple input multiple output Further evolution of MIMO in LTE.

We can usually divide the antenna array into two parts: the physical antenna array and the transceiver channel array. Traditional MIMO technology is mainly based on a one-dimensional antenna array (usually a horizontal-dimensional antenna array), as shown in Figure 1. Specifically, its physical antenna array may be two-dimensional (the physical antenna array in Figure 1 is 8 rows and 8 columns), but the transceiver channel array is one-dimensional (the transceiver channel array in Figure 1 is 1 row and 8 columns), and multiple physical antenna elements with the same polarization in the same column are connected to the same transceiver channel. Therefore, only the phase difference between multiple physical antenna elements in the horizontal dimension can be adjusted, but the phase difference between multiple physical antenna elements in the vertical dimension cannot be adjusted, so traditional MIMO can only perform beams in the horizontal dimension The shape of the beam in the vertical dimension is fixed (usually the 3dB bandwidth in the vertical dimension is about 10 degrees), the beam in Figure 1 can only be adjusted in the horizontal dimension, but the direction of the vertical dimension is fixed (generally determined by the following depending on the angle of inclination).

Since traditional base stations have fixed beam width and orientation in the vertical dimension regardless of whether they are service beams or broadcast beams, generally speaking, the 3dB bandwidth in the vertical dimension is about 10 degrees. Therefore, in the actual environment, users are distributed in a large vertical dimension , traditional base stations cannot cover all users well.

Contents of the invention

In order to improve the broadcast coverage of a base station, the present invention provides an antenna array and a method for transmitting signals by a base station.

In order to achieve the above object, the present invention provides an antenna array, which includes:

A physical antenna array and a transceiver channel array corresponding to the physical antenna array, and part of the antenna units in the physical antenna array correspond to high-power transceiver channels, and the remaining antennas in the physical antenna array except the part of the antenna units The unit corresponds to a standard power transceiving channel, wherein the transmission power supported by the high power transceiving channel is greater than the transmission power supported by the standard power transceiving channel.

Optionally, the antenna array is a full-dimensional multiple-input multiple-output FD-MIMO LTE antenna.

Optionally, the part of the antenna units is arranged around the center of the physical antenna array.

Optionally, the antenna units in the physical antenna array are dual-polarized antenna units.

According to another aspect of the present invention, the present invention also provides a method for a base station to transmit signals, the base station including an antenna array, the method comprising:

Perform beamforming and transmit broadcast beams according to the physical downlink shared channel PDSCH and/or common control signal of the transmission mode that uses the cell-specific reference signal CRS for data demodulation sent by the high-power transceiving channel; and

According to the service data sent on the high-power transceiving channel and the standard power transceiving channel, the beamforming of the service beam is performed and sent, wherein the high-power transceiving channel and the standard power transceiving channel are jointly used for sending service data.

Optionally, the common control signal includes: at least one of a cell-specific reference signal CRS, a primary synchronization signal PSS, a secondary synchronization signal SSS, a physical broadcast channel PBCH, and a physical downlink control channel PDCCH.

Optionally, the service data is service data carried by a PDSCH, wherein the PDSCH is a PDSCH in a transmission mode that uses a demodulation reference signal DMRS to perform data demodulation.

The beneficial effects of the present invention are:

The present invention utilizes that some antenna units in the provided physical antenna array correspond to high-power transceiver channels, and the remaining antenna units in the physical antenna array except some antenna units correspond to antenna arrays of standard power transceiver channels. The physical downlink shared channel PDSCH and/or common control signal of the transmission mode that uses the cell-specific reference signal CRS for data demodulation is beam-formed and sent on the broadcast beam, and according to the high-power transceiving channel and the standard power transceiving channel The service data to be sent is beam-formed on the service beam and sent. Utilize the principle that the beam of a single antenna unit is a wide beam, and multiple antenna units can form a wide beam after citing broadcast shaping weights. The present invention only uses high-power transceiver channels for PDSCH and/or public control signals to send broadcast beams , avoiding the power loss caused by multiple antenna units when introducing broadcast shaping weights, that is, reducing the weight loss during beamforming, and improving the broadcast coverage of the base station when forming wide beams; and due to the high power transceiver The transmission power supported by the channel is greater than that supported by the standard power transceiver channel, so even if a small number of high-power transceiver channels are used and a small amount of weight loss occurs, the broadcast beam formed is also a wide beam, which also improves the broadcast coverage of the base station.

Description of drawings

Figure 1 shows an existing one-dimensional antenna array;

Figure 2 shows an existing two-dimensional antenna array;

Fig. 3 shows one of the schematic diagrams of the physical antenna array in the antenna array in the embodiment of the present invention;

FIG. 4 shows a flow chart of main steps of a method for transmitting signals by a base station in an embodiment of the present invention; and

Fig. 5 shows the second schematic diagram of the physical antenna array in the antenna array in the embodiment of the present invention.

Among them:

1. Physical antenna array; 2. Transceiver channel; 3. Some antenna units; 4. Remaining antenna units.

detailed description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided for more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

Full-dimensional multiple-input multiple-output FD-MIMO is mainly based on a two-dimensional antenna array (multiple antenna elements in the same row are connected to multiple transceiver channels), as shown in Figure 2, where physical antenna array 1 and transceiver channel 2 are two dimensional array. The power supported by each transceiver channel corresponding to the two-dimensional antenna array of FD-MIMO is consistent. For example, the total transmit power of the FD-MIMO base station is 40W, and there are 64 channels in total. Generally speaking, the power of each channel is (40/64 ) W can.

At present, the two-dimensional antenna array used by FD-MIMO in 3GPP can be described by the following parameters (M, N, P, M_TXRU), where M represents the number of arrays of a column of antennas with the same polarization, and N represents the number of columns of the antenna array. P=2 indicates that a dual-polarized antenna is used, and M_TXRU indicates the number of transceiver channels corresponding to the same array of antenna elements. One transceiver channel may correspond to several antenna elements, and Q=2N*M_TXRU indicates that in the array of transceiver channels corresponding to the antenna array The total number of transmit and receive channels. For example, the total number of transceiver channels Q corresponding to the antenna array (M, N, P, M_TXRU)=(8,4,2,4) is 32.

Specifically, the physical antenna array and the transceiver channel array of the two-dimensional antenna array are both two-dimensional, and each physical antenna element corresponds to a transceiver channel, so that not only the phase difference between multiple physical antenna elements in the horizontal dimension can be adjusted, Moreover, the phase difference between multiple physical antenna elements in the vertical dimension can also be adjusted. FD-MIMO can not only perform beamforming in the horizontal dimension, but also perform beamforming in the vertical dimension. Although FD-MIMO can form a narrower service beam and can adjust the orientation in the vertical dimension so that the maximum beam direction points to the user, but for the broadcast beam, since the common control signals such as the cell-specific reference signal CRS and the physical downlink control channel PDCCH depend on the broadcast beam , in order to cover users at different heights in the cell as much as possible, FD-MIMO needs to form a wider broadcast beam. In addition, among the transmission modes, TM2, TM3 and other transmission modes that rely on CRS for demodulation will also be affected by the broadcast beam gain.

FD-MIMO generally forms broadcast beams by broadcasting shaping weights. Generally speaking, the beam width of each antenna unit is wide (typically 65 degrees, 90 degrees, etc.). Therefore, it is necessary to let the two-dimensional antenna array form a broadcast Beam, its broadcast shaping weight will introduce a certain power loss, the more the number of antenna elements, the greater the power loss that may be introduced. Taking the horizontal 3dB width and vertical 3dB width of a single antenna unit beam as an example, for a 64TXRU antenna array with (M,N,P,M_TXRU)=(8,4,2,64), if you want to form For a horizontal broadcast beam of about 60 degrees and a vertical broadcast beam of about 60 degrees, the broadcast weight will bring a large weight loss. For example, the signal amplitude weight of the horizontal broadcast beam Am=[0.45,1,1,0.53], Phase Pm=[120,149,156,328], the signal amplitude weight of the vertical broadcast beam is Am=[0.45,1,0.9,0.4,0.9,1,0.45], phase Pm=[0,90,165,-120,-190,175,90, -10], the weight loss caused by the signal amplitude weight of the horizontal broadcast beam is about -2.07dB, the weight loss caused by the signal amplitude weight of the vertical broadcast beam is about -2.65dB, and the total weight loss is about - 4.72dB.

The weight loss of broadcast shaping weights will reduce the gain of broadcast beams, thereby reducing the coverage performance of public control signals such as CRS and PDCCH. In addition, transmission modes such as TM2 and TM3 that rely on CRS for demodulation will also be affected.

Embodiments of the present invention provide an antenna array that divides the transceiver channel array into high-power transceiver channels and standard power transceiver channels, and distinguishes and transmits the signals of the base station according to the provided antenna array, reducing the broadcast weight loss of the base station And the broadcast coverage of the base station is improved. The following will be further described in conjunction with specific embodiments.

As shown in FIG. 3 , it is one of the schematic structural diagrams of the physical antenna array in the antenna array in the embodiment of the present invention. The antenna array includes a physical antenna array and a transceiver channel array corresponding to the physical antenna array, and part of the antenna units 3 in the physical antenna array correspond to high-power transceiver channels, and the remaining antenna units 4 in the physical antenna array except part of the antenna unit 3 correspond to For the standard power transceiver channel, the transmission power supported by the high power transceiver channel is greater than that supported by the standard power transceiver channel.

Specifically, according to the principle that the total power transmitted by the base station remains unchanged, the transmit power supported by the high-power transceiver channel is the ratio of the transmit power of the base station to the total number of high-power transceiver channels, and the transmit power supported by the standard power transceiver channel is the base station's The ratio of transmit power to the total number of transceiver channels. For example, if the total transmit power of the base station is 40W, the total number of transceiver channels is 64, and the number of high-power transceiver channels is 2, then the transmit power supported by the standard power transceiver channel is 40/64W, and the transmit power supported by the high-power transceiver channel is for 20W.

In the antenna array provided by this embodiment, part of the antenna units 3 in the physical antenna array correspond to high-power transceiving channels, and the remaining antenna units 4 in the physical antenna array except the part of the antenna units 3 correspond to standard power transceiving channels, which solves the problem of The existing FD-MIMO two-dimensional antenna array corresponds to the problem that the power levels supported by each transceiver channel are consistent.

Optionally, the antenna array of the base station is a full-dimensional multiple-input multiple-output FD-MIMO LTE antenna, and the antenna units in the physical antenna array in the antenna array are dual-polarized antenna units.

Optionally, referring to FIG. 1 , in order to improve the broadcast coverage of the base station, some antenna units 3 corresponding to high-power transceiver channels are arranged around the center of the physical antenna array.

According to another aspect of the present invention, a method for transmitting a signal by a base station is also provided, wherein the base station includes an antenna array. As shown in FIG. 4, the flow chart of the main steps of the method for sending signals to the base station mainly includes the following steps:

Step 101 , according to the physical downlink shared channel PDSCH and/or common control signal of the transmission mode sent by the high-power transceiver channel using the cell-specific reference signal CRS for data demodulation, perform beamforming of the broadcast beam and send it.

In this step, the PDSCH and/or common control signals are sent using a high-power transceiver channel. Specifically, using the principle that the beam of a single antenna unit is a wide beam, multiple antenna units can form a wide beam only after citing broadcast shaping weights. In this step, only high-power transceiver channels are used to broadcast PDSCH and/or public control signals. The transmission of beams avoids the power loss caused by using multiple antenna units when introducing broadcast shaping weights, that is, reduces the weight loss during beam forming, and improves the broadcast coverage of the base station when forming wide beams; and Since the transmission power supported by the high-power transceiver channel is greater than that of the standard power transceiver channel, the signal amplitude can be used without signal amplitude weighting, that is, without power loss, or when a small number of high-power transceiver channels are used for beamforming The weight value means that in the case of a small amount of power loss, the effect of reducing the weight value loss of the base station and improving the broadcast coverage of the base station can also be achieved.

Specifically, the common control signal includes: at least one of a cell-specific reference signal CRS, a primary synchronization signal PSS, a secondary synchronization signal SSS, a physical broadcast channel PBCH, and a physical downlink control channel PDCCH.

Step 102 , according to the service data sent on the high-power transceiver channel and the standard-power transceiver channel, perform beamforming of the service beam and send it.

In this step, the base station may perform beamforming and transmit the service beam according to the service data sent on the high-power transceiver channel and the standard-power transceiver channel. Specifically, the service data is service data carried by the PDSCH, wherein the PDSCH is a PDSCH in a transmission mode that uses a demodulation reference signal DMRS to perform data demodulation.

In this embodiment, the high-power transceiver channel is used to send the PDSCH and/or the common control signal, and the high-power transceiver channel and the standard power transceiver channel are used to send service data. Using the principle that the beam of a single antenna unit is a wide beam, multiple antenna units can form a wide beam after citing broadcast shaping weights, and only use high-power transceiver channels for PDSCH and/or public control signals to send broadcast beams to avoid The power loss caused by multiple antenna units when introducing broadcast shaping weights is reduced, that is, the weight loss during beamforming is reduced, and the broadcast coverage of the base station is improved when wide beams are formed; and because the high-power transceiver channel supports The transmit power is greater than the transmit power supported by the standard power transceiver channel, so even if a small number of high-power transceiver channels are used and a small amount of weight loss is generated, the broadcast beam formed is also a wide beam, which also improves the broadcast coverage of the base station.

The above-mentioned embodiments are explained below with two specific embodiments.

Embodiment one:

As shown in Figure 3, in Figure 3, the physical antenna array has 8 rows and 8 columns, that is, the physical antenna array corresponds to 64 transceiver channels, and the fifth row and the second column in the physical antenna array correspond to two high-power Part of the antenna units 3 of the transceiver channel, and the remaining antenna unit 4 correspond to the standard power transceiver channel. It can be seen from the figure that some antenna units 3 are arranged around the center of the physical antenna array. Assuming that the total transmit power of the base station corresponding to the physical antenna array in Figure 3 is 40W, the transmit power supported by the two high-power transceiver channels is 20W, and the transmit power supported by the standard power transceiver channel is 40/64W.

In this embodiment, the PDSCH and/or common control signals (at least one of CRS, PSS, SSS, PBCH, and PDCCH) are sent using two high-power transceiving channels corresponding to some antenna units 3 . In this process, since the transmission power supported by the high-power transceiver channel is higher than that supported by the standard transceiver channel, even if the two high-power transceiver channels generate a small amount of weight loss in the process of beamforming to form a wide beam, it still does not Affecting the transmission of PDSCH and/or public control signals (at least one of CRS, PSS, SSS, PBCH, and PDCCH), while reducing the weight loss of the base station, expands the broadcast coverage of the base station. In addition, since the service data transmission requirements are relatively low, the service data (service data that can be carried by the PDSCH) is simultaneously transmitted using a high-power transceiving channel and a standard power transceiving channel.

Embodiment two:

As shown in FIG. 5 , it is the second schematic diagram of the physical antenna array in the antenna array in the embodiment of the present invention. In Figure 5, the physical antenna array is also 8 rows and 8 columns, that is, the physical antenna array corresponds to 64 transceiver channels, and in the physical antenna array, the second column of the fourth row and the second column of the fifth row correspond to 4 Part of the antenna units 3 of the high-power transceiving channel, and the remaining antenna units 4 correspond to the standard power transceiving channel. It can be seen from the figure that some antenna units 3 are arranged around the center of the physical antenna array. Assuming that the total transmit power of the base station corresponding to the physical antenna array in Figure 5 is 40W, the transmit power supported by the four high-power transceiver channels is 10W, and the transmit power supported by the standard power transceiver channels is 40/64W.

In this embodiment, the PDSCH and/or common control signals (at least one of CRS, PSS, SSS, PBCH, and PDCCH) are sent using four high-power transceiving channels corresponding to some antenna units 3 . In this process, since the transmit power supported by the high-power transceiver channel is higher than that supported by the standard transceiver channel, even if the four high-power transceiver channels generate a small amount of weight loss in the process of beamforming to form a wide beam, it still does not Affecting the transmission of PDSCH and/or public control signals (at least one of CRS, PSS, SSS, PBCH, and PDCCH), while reducing the weight loss of the base station, expands the broadcast coverage of the base station. In addition, since the service data transmission requirements are relatively low, the service data (service data that can be carried by the PDSCH) is simultaneously transmitted using a high-power transceiving channel and a standard power transceiving channel.

The invention utilizes the principle that the beam of a single antenna unit is a wide beam, and multiple antenna units can form a wide beam only after citing broadcast shaping weights, and only use high-power transceiver channels for PDSCH and/or public control signals to send broadcast beams , which avoids the power loss caused by multiple antenna units when introducing broadcast shaping weights, that is, reduces the weight loss during beamforming, and improves the broadcast coverage of the base station when forming wide beams; in addition, due to the high power The transmission power supported by the transceiver channel is greater than that supported by the standard power transceiver channel, so even if a small number of high-power transceiver channels are used and a small amount of weight loss is generated, the broadcast beam formed is also a wide beam, which also improves the broadcast coverage of the base station .

What has been described above is a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, some improvements and modifications can be made without departing from the principles described in the present invention. within the scope of protection of the invention.

Claims (7)

1. An antenna array applied to a base station, wherein the antenna array comprises: A physical antenna array and a transceiver channel array corresponding to the physical antenna array, and part of the antenna units in the physical antenna array correspond to high-power transceiver channels, and the remaining antennas in the physical antenna array except the part of the antenna units The unit corresponds to a standard power transceiving channel, wherein the transmission power supported by the high power transceiving channel is greater than the transmission power supported by the standard power transceiving channel. 2 . The antenna array according to claim 1 , wherein the antenna array is a full-dimensional multiple-input multiple-output FD-MIMO LTE antenna. 3. The antenna array according to claim 1, wherein the part of the antenna elements is arranged around the center of the physical antenna array. 4. The antenna array according to claim 1, wherein the antenna elements in the physical antenna array are dual-polarized antenna elements. 5. A method for transmitting signals by a base station, wherein the base station comprises the antenna array according to any one of claims 1 to 4, the method comprising: Perform beamforming and transmit broadcast beams according to the physical downlink shared channel PDSCH and/or common control signal of the transmission mode that uses the cell-specific reference signal CRS for data demodulation sent by the high-power transceiving channel; and According to the service data sent on the high-power transceiving channel and the standard power transceiving channel, the beamforming of the service beam is performed and sent, wherein the high-power transceiving channel and the standard power transceiving channel are jointly used for sending service data. 6. The method according to claim 5, wherein the common control signal comprises: cell-specific reference signal CRS, primary synchronization signal PSS, secondary synchronization signal SSS, physical broadcast channel PBCH and physical downlink control channel PDCCH at least one. 7. The method according to claim 5, wherein the service data is service data carried by a PDSCH, wherein the PDSCH is a PDSCH in a transmission mode for data demodulation using a demodulation reference signal DMRS.