A kind of 5G large-scale antenna array beam forming device and method
[technical field]
The invention belongs to wireless communication technology fields, in particular to a kind of to be suitable for 5G large-scale antenna array beam forming
Device and method.
[background technique]
On December 20th, 2017, in the 78th plenary session of 3GPP RAN, 5G NR (New Radio) starting version is just
Formula is freezed and is issued, and 5G standardization welcomes important milestone.The relevant manufactures and mechanism of China are not only in normal structures such as 3GPP
In played important function, walked before the world in terms of technical testing, frequency spectrum.What IMT-2020 propulsion group was dominated
Emphasis turns to research and development of products, verifying and industry cooperation before 5G commercialization to the test of 5G technical research, and the interconnection before carrying out commercialization is mutual
Logical work.Domestic relevant manufactures have carried out second stage test since in June, 2016, construct the maximum test in the scale whole world
Net simultaneously achieves good achievement.The complete standard of 5G will be estimated to be completed in the end of the year 2019, and International Telecommunication Association's recommendation finally will packet
Whole technical specifications containing IMT-2020.
Single base station will be allowed to reach the downstream rate of 20Gbps or more and the speed uplink of 10Gbps under the 5G network system.
All user sharing whole bandwidth of one cell, every square kilometre of support number of users are up to 1,000,000.Its skill mainly used
Art has: millimeter wave (mmWave), large-scale antenna array etc..Wherein, millimeter wave frequency band is since its wavelength is short, path loss is big,
Cause propagation distance limited.Therefore, it is necessary to use large-scale antenna array to obtain high directional gain and increase covering.It is restricted
In the limitation of power consumption and cost, base station antenna unit quantity is penetrated rf chain number most tens between 100-1000
Frequency link quantity will be substantially less that antenna element quantity.Therefore, it is necessary to radio frequency link to need to use between antenna phase shifter with
Complete beam forming function.
It is assumed that base station radio-frequency number of links is N, antenna number M, existing beam forming method has as follows: the wave beam connected entirely
Molding scheme, as shown in Figure 1, radio frequency link is connected between antenna using phase shifter in the program, then the phase shifter number needed
Amount is N*M.Such as: antenna number is 64, rf chain number is 8, then the phase shifter quantity needed is 512.With antenna amount
And rf chain number increases, the phase shifter quantity needed will increase sharply, so that complexity and cost are too high, are difficult to reality
Large-scale application, practicability are poor.
[summary of the invention]
The object of the present invention is to provide a kind of 5G large-scale antenna array beam forming device and methods, to solve existing day
The problem of linear array is at high cost, complexity is high, the practicability is poor.
The invention adopts the following technical scheme: it is a kind of suitable for 5G large-scale antenna array beam forming device, including with
In the pre-coding matrix F that base-band data stream is carried out precoding and exportedB, the pre-coding matrix FBOutput end pass through difference
Data transmission link is respectively connected to N number of radio frequency link, and the output end of each radio frequency link passes through data transmission link
It is connected to antenna array unit, is provided with shifting between the outlet line and the antenna array unit of each radio frequency link
Phase device, the antenna array unit are divided into N group;The phase shifter composition simulation pre-coding matrix FR,
Wherein, G is integer, and G=M/N, M are the sum of antenna array unit,Indicate that i-th of radio frequency link is corresponding
The phase of k-th of phase shifter in j-th of antenna array unit group.
Further, the outlet line of i-th of radio frequency link isAnd it is respectively connected toIt is connect after a phase shifter with antenna array unit.
Further, the quantity for the phase shifter that each antenna array unit in jth group antenna array unit is connected is
j。
Another technical solution of the invention, a kind of beam forming method suitable for 5G large-scale antenna array use
Above-mentioned one kind is suitable for 5G large-scale antenna array beam forming device, is calculated according to the distance between N number of user and base station
Link load obtains the signal-to-noise ratio of each user;
The signal-to-noise ratio of N number of user is ranked up from low to high, the user 1 after obtaining sequence to user N;
Radio frequency link 1-N is respectively corresponded and distributes to user 1-N.
The beneficial effects of the present invention are: large-scale antenna array is grouped by the present invention, the shifting being connected with every group of antenna element
The distribution of phase device quantity ladder, then connects the phase shifter that ladder is distributed with radio frequency link respectively, provides a kind of completely new
Connection method, compared with full connection method in the prior art, whole system need phase shifter quantity sharp fall.When
In cellular cell when user's random distribution, using this method compared with full connection method, the overall spectral efficiency of system and
Energy efficiency decline is negligible, and system complexity and cost will be effectively reduced especially suitable for 5G base station system in this method.
[Detailed description of the invention]
Fig. 1 is the beam forming schematic diagram connected entirely in the prior art;
Fig. 2 is beam forming schematic diagram in the embodiment of the present invention;
Fig. 3 is user's communication scheme in base station and cell.
[specific embodiment]
The following describes the present invention in detail with reference to the accompanying drawings and specific embodiments.
The invention discloses one kind to be suitable for 5G large-scale antenna array beam forming device, as shown in Fig. 2, including being used for
The pre-coding matrix F that base-band data stream is carried out precoding and exportedB, L base-band data stream (1,2 ..., L) in the present embodiment
Enter pre-coding matrix FBIn handled, the base-band data stream exported after precoding be N number of, i.e., 1,2 ..., N,
And having L≤N, L, N are the integer greater than 0, pre-coding matrix FBOutput end prelisted N number of by different data transmission line
Base-band data stream after code is sent respectively into N number of radio frequency link.
The output end of each radio frequency link passes through data transmission link and is connected to antenna array unit, antenna array unit
Number is M (M >=N, M, N are integer, and M is the integral multiple of N), is divided into N group (1,2 ..., N), and every group has M/N unit,
In, first group of each antenna array unit is separately connected 1 phase shifter, and second group of each antenna array unit is separately connected 2
Phase shifter, i.e. second group of each antenna array unit receive the composite signal from 2 phase shifters, and so on, N group is every
A antenna array unit is separately connected N number of phase shifter, that is, each antenna array unit for receiving N group is received from N number of shifting
The composite signal of phase device.
The outlet line of i-th of radio frequency link is1≤i≤N, and be respectively connected to
It is connect after a phase shifter with antenna array unit.Radiofrequency signal is divided into the road M by radio frequency link 1, is connected respectively to and 1-N group day
On the phase shifter that linear array column unit is connected;To which radio frequency link 1 is connected with M antenna element respectively.Radio frequency link 2 will be penetrated
Frequency signal is divided into the road (M-M/N), is connected respectively on the phase shifter being connected with 2-N group antenna array unit, i.e. rf chain
Road 2 is connected with M* (1-1/N) a antenna array unit, and so on, radiofrequency signal is divided into the road M/N by radio frequency link N, is connected respectively
It is connected on the phase shifter being connected with N group antenna array unit, i.e., radio frequency link N is connected with M/N antenna array unit.
Phase shifter, jth (1≤j≤N) group are provided between the outlet line and antenna array unit of each radio frequency link
The quantity for the phase shifter that each antenna array unit in antenna array unit is connected is j, i.e. in the 1st group of antenna array unit
Each antenna array unit be separately connected 1 phase shifter, each antenna array unit in the 2nd group of antenna array unit difference
2 phase shifters are connected, and so on, each antenna array unit in N group antenna array unit is separately connected N number of phase shift
Device.
To sum up, phaser array composition simulation pre-coding matrix FR, be not zero data element ladder distribution, that is,
Wherein, G is integer, G=M/N,It indicates in corresponding j-th of antenna array unit group of i-th of radio frequency link
The phase of kth (1≤k≤M/N) a phase shifter.
The invention also discloses a kind of beam forming methods suitable for 5G large-scale antenna array, use above-mentioned one kind
Suitable for 5G large-scale antenna array beam forming device, as shown in figure 3, having when working as user's random distribution in cell
User distance base station is closer, and link load is smaller, and link load is big farther out for some user distance base stations, selects N number of user couple every time
It provides service, calculates link load according to the distance between N number of user and base station, obtains the signal-to-noise ratio of each user.
Base station will be ranked up from low to high according to the signal-to-noise ratio of N number of user, the user 1 after obtaining sequence to user N.By
M antenna element is connected in radio frequency link 1, most narrow wave beam is capable of providing, and its directional gain is maximum, by radio frequency link 1
The worst user 1 of signal-to-noise ratio is distributed to, radio frequency link 2 distributes to user 2 and so on, since radio frequency link N only connects M/N
Antenna element, so radio frequency link N is distributed to the best user N of signal-to-noise ratio.Radio frequency link 1-N is respectively corresponded and is distributed to
User 1-N.
Embodiment 1: assuming that shared antenna element number M=64, number of data streams N=8, then using as shown in Figure 1 complete
The phase shifter quantity that connection method needs is 64*8=512, the phase shifter quantity needed using this method are as follows: 8+8*2+ ...+8*8
=288.As it can be seen that the quantity of phase shifter is needed to be greatly reduced.
Embodiment 2: assuming that whole antenna number M=256, number of data streams N=16, then need to move using full connection method
Phase device quantity is 4096, the phase shifter quantity needed using this method are as follows: 16+16*2+ ...+16*16=2176.
In addition, other antennas are as follows: with radio frequency link configuration comparison