KR101323378B1 - Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network - Google Patents

Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network Download PDF

Info

Publication number
KR101323378B1
KR101323378B1 KR1020120135450A KR20120135450A KR101323378B1 KR 101323378 B1 KR101323378 B1 KR 101323378B1 KR 1020120135450 A KR1020120135450 A KR 1020120135450A KR 20120135450 A KR20120135450 A KR 20120135450A KR 101323378 B1 KR101323378 B1 KR 101323378B1
Authority
KR
South Korea
Prior art keywords
receiver
sender
sum rate
selection
rate information
Prior art date
Application number
KR1020120135450A
Other languages
Korean (ko)
Inventor
김상효
강진환
조충기
Original Assignee
성균관대학교산학협력단
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 성균관대학교산학협력단 filed Critical 성균관대학교산학협력단
Priority to KR1020120135450A priority Critical patent/KR101323378B1/en
Application granted granted Critical
Publication of KR101323378B1 publication Critical patent/KR101323378B1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/022—Site diversity; Macro-diversity
    • H04B7/024—Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/0413—MIMO systems
    • H04B7/0417—Feedback systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Radio Transmission System (AREA)

Abstract

The present invention discloses an apparatus and method for transmitting rate related information for recipient selection in a multi-cell multi-input downlink network, and an apparatus, method and system for receiver selection in a multi-cell multi-input downlink network. In a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group of the present invention, a method for transmitting rate-related information to a sender for receiver selection includes receiving a pilot signal from the sender; Calculating approximate sum rate information assuming a non-linear receiver based on a pilot signal, and transmitting the approximated sum rate information to the sender. Therefore, it is possible to select a receiver capable of achieving a computational complexity similar to that of the conventional scheme and a higher sum rate than the conventional scheme.

Description

FIELD OF THE INVENTION Apparatus and method for transmitting rate related information for receiver selection in a multi-cell multi-input downlink network, and apparatus, method and system for selecting a receiver in a multi-cell multi-input downlink network. RECEIVER SELECTION IN MULTI CELL MIMO DOWNLINK NETWORK, AND RECEIVER SELECTION APPARATUS, METHOD AND SYSTEM IN MULTI CELL MIMO DOWNLINK NETWORK}

The present invention relates to an apparatus, a method and a system related to opportunistic user selection, and more particularly, to a multi-cell multiple input multiple output (MIMO) downlink system environment. An apparatus, method, and system for opportunistic user selection that can be applied in the present invention.

A multi-cell multi-output multi-input downlink network is a situation in which a plurality of base stations exist and a group of recipients to which each base station receives information is assigned. It has an antenna

In order to perform the optimized beamforming in the considered network, it is necessary to transmit channel information with considerable overhead. Opportunity beamforming is a technique for reducing such overhead. The opportunistic beamforming technique is a technique in which a sender creates an arbitrary matrix and finds an optimized user in the current situation in a situation where one sender has a receiver group composed of a plurality of receivers. At this time, the receiver receives channel information from the sender and returns a reference value for user selection so that the receiver selects a user from the sender. The advantage of this technique is that beamforming only transmits a reference value for receiver selection with less overhead, whereas channel information with large overhead needs to be transmitted between the sender and receiver in order to implement the optimized beamforming technique. Assuming that the overhead is small and the number of receivers is sufficient, a bit rate similar to that of a conventional beamforming scheme can be achieved.

Opportunistic Interference Alignment User Selection (OIAUS) is a technique derived from interference alignment (OIAUS) and selects the most highly correlated user based on correlation of interference signals. In this way, the opportunistic beamforming technique had to apply a singular value decomposition (SVD) process to all users by allowing only selected users to generate a beamforming matrix. The selection technique further reduces the complexity by applying the singular value decomposition (SVD) process only to the selected users. However, the opportunistic interference alignment user selection technique has a disadvantage in that the sum rate performance is not good because the power of the interference transmission signals is not taken into account when the user is adopted.

SUMMARY OF THE INVENTION An object of the present invention for solving the above problems is that in a multi-cell multi-input / output downlink network having a large number of senders and each sender having a group consisting of a plurality of receivers, the highest sum rate can be achieved only by a low complexity operation. An apparatus and method for transmitting rate related information for receiver selection in a multi-cell multi-input downlink network and a receiver selection apparatus, method and system in a multi-cell multi-input downlink network are provided.

In a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group of the present invention for achieving the above object, a method for transmitting rate-related information to a sender for receiver selection includes receiving a pilot signal from the sender. Receiving, calculating the approximate sum rate information assuming a non-linear receiver based on the received pilot signal and transmitting the approximated sum rate information to the sender.

The calculating of the approximate sum rate information calculates the approximated sum rate information based on the sum of the variance matrix of the interference signals of other receivers existing in the current receiver group and the variance matrix of the self-designated signal. It may include the step.

The approximated sum rate information calculating step

Figure 112012098223821-pat00001
Where w is the approximate sum rate, I N is the unit matrix of N × N, Q [j, ki ] is the sum of the variance matrices of the interference signals of the k-th receiver in the i-th group, and Q [i, ki ] is calculating the approximate sum rate information using the distribution matrix of the designation signal for the k-th receiver in the i-th group).

The sender may transmit a selection signal by selecting a receiver having transmitted the largest value among at least one of the approximated sum rate information received from the receiver belonging to the receiver group corresponding to the sender.

The transmission rate-related information transmission method generates a reception beamforming matrix capable of maximizing a transmission rate by using a singular value decomposition (SVD) technique when receiving the selection signal from the transmitter, thereby interfering with the transmitter. The method may further include executing communication in a situation.

The pilot signal may include local channel knowledge.

In the multi-cell multi-input downlink network having a plurality of sender groups and a receiver group of the present invention for achieving the above object, an apparatus for transmitting a rate-related information to a sender for receiver selection includes receiving a pilot signal from the sender. It may include a receiving unit for receiving, a calculating unit for calculating approximate sum rate information assuming a nonlinear receiver based on the received pilot signal, and a transmitting unit for transmitting the approximated sum rate information to the sender.

A method for selecting a receiver in a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group of the present invention for achieving the above object comprises the steps of: transmitting a pilot signal to each receiver, corresponding receiver Receiving at least one approximate sum rate information calculated on the assumption of a nonlinear receiver from at least one receiver belonging to a group, and selecting a receiver having transmitted the largest value among the at least one approximated sum rate information received And transmitting the selection signal.

The approximate sum rate information is

Figure 112012098223821-pat00002
Where w is the approximate sum rate, I N is the unit matrix of N × N, Q [j, ki ] is the variance matrix of the interference signal of the k-th receiver in the i-th group, and Q [i, ki ] is the i-th Information may be calculated using the distribution matrix of the designation signal for the k-th receiver in the group).

The method of selecting a receiver may further include receiving reception beamforming matrix information from the selected receiver to perform communication in an interference channel situation.

The receiver selection method may further include generating a random transmission beamforming matrix and generating the pilot signal based on the random beamforming matrix.

In order to achieve the above object, an apparatus for selecting a receiver in a multi-cell multi-input downlink network having a plurality of transmitter groups and a receiver group of the present invention includes a pilot signal transmitter for transmitting a pilot signal to each receiver; The largest value of the sum rate information receiver and the received at least one approximated sum rate information, which receives at least one approximated sum rate information calculated on the assumption of a nonlinear receiver from at least one receiver belonging to the corresponding receiver group, It may include a selection signal transmission unit for transmitting the selection signal by selecting the receiver to be transmitted.

A system for receiver selection in a multi-cell multi-input downlink network having multiple sender groups and receiver groups of the present invention for achieving the above object receives a pilot signal from a sender and receives the received pilot signal. Based on the assumption of a non-linear receiver, the approximate sum rate information is calculated, the receiver for transmitting the approximate sum rate information to the sender and the pilot signal are transmitted to each receiver, and belonging to a corresponding receiver group. It may include a sender for receiving the at least one approximated sum rate information from at least one receiver to select a receiver having transmitted the largest value of the at least one approximated sum rate information to transmit a selection signal .

The receiver may calculate the approximate sum rate information on the assumption that the receiver is a nonlinear receiver based on the sum of the variance matrix of the interference signals of the other receivers present in the current receiver group and the variance matrix of the self-designated signal.

The recipient is

Figure 112012098223821-pat00003
Where w is the approximate sum rate, I N is the unit matrix of N × N, Q [j, ki ] is the variance matrix of the interference signal of the k-th receiver in the i-th group, and Q [i, ki ] is the i-th The approximate sum rate information may be calculated using the variance matrix of the designation signal for the k-th receiver in the group.

When the receiver receives the selection signal from the sender, the receiver generates a reception beamforming matrix capable of maximizing a transmission rate using a singular value decomposition (SVD) technique to communicate with the sender in an interference channel situation. You can run

According to the present invention, an apparatus and method for transmitting rate related information for receiver selection in a multi-cell multi-input downlink network, and a receiver selection apparatus, method and system in a multi-cell multi-input downlink network, are similar to those of the conventional scheme. It is possible to select a receiver that can achieve a computational complexity, a higher aggregate transfer rate than the conventional method, and the present invention is limited to only three users, whereas the present invention can be applied to any number of users. have.

1 is a conceptual diagram of a MIMO downlink network system having M transmitters;
2 is a flow chart of opportunistic interference alignment user selection;
3 is a flowchart illustrating a receiver selection method in a multi-cell multi-input / output downlink network according to an embodiment of the present invention;
4 is a block diagram schematically illustrating an apparatus for transmitting rate related information for selecting a receiver in a multi-cell multi-input / output downlink network according to an embodiment of the present invention;
5 is a block diagram schematically illustrating an apparatus for selecting a receiver in a multi-cell multiple input / output downlink network according to an embodiment of the present invention;
6 is a view showing a result of comparing a receiver selection method and a conventional computational complexity in a multi-cell multi-input downlink network according to an embodiment of the present invention;
FIG. 7 illustrates a comparison between a receiver selection method and a conventional transmission rate in a multi-cell multi-input / output downlink network according to an embodiment of the present invention.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the relevant art and are to be interpreted in an ideal or overly formal sense unless explicitly defined in the present application Do not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the understanding of the present invention, the same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

Throughout this specification, a transmitter refers to an apparatus for performing data communication, that is, a transmitter, and a receiver refers to an apparatus for communicating with the sender and receiving data, that is, a receiver. . The recipient may also be referred to as a user.

In the opportunistic beamforming scheme, a transmitter arbitrarily forms a transmission beamforming matrix, and then each receiver receives local channel information based on the transmission beamforming matrix, and transmits a user selection value to the transmitter. Then, the sender can select and communicate with the receiver in such a manner that the receiver selects the optimized receiver in the current situation, and this method can achieve a high transmission rate when a sufficient number of receivers 22 are present.

Multicell Multiple Inputs and Outputs Downlink  Recipient Selection System in the Network

1 is a conceptual diagram of a MIMO downlink network system having M transmitters. As shown in Fig. 1, the MIMO downlink network system includes M senders 10-1, 10-2, ..., 10-M and M receiver groups 20-1, 20-2, .. , 20-M), and each recipient group may include at least one recipient 22.

Referring to FIG. 1, there are M senders 10-1, 10-2, ..., 10-M in the network, and each sender 10-1, 10-2, ..., 10-. M) has a recipient group 20-1, 20-2, ..., 20-M consisting of K recipients 22-1, 22-2, ..., 22-K. Assume that there is no information exchange between each sender 10. Each sender 10 has a corresponding recipient group 20. For example, sender 1 10-1 corresponds to receiver group 1 20-1, sender 2 10-2 corresponds to receiver group 2 20-2, and so on. May have Thus, the sender 10 selects one of the corresponding recipient groups 20 as the optimized receiver 22 is an important factor for communication with minimal interference.

In addition, each receiver 22 may know only local channel information coming into it, and after receiving channel information from the senders 10, the receiver 22 may determine a rate-related information value generated through a series of calculation processes. Return to sender 10. The sender 10 selects the optimized receiver 22 based on the transmission rate related information value received from the receiver. The selected receiver 22 generates its own receive beamforming matrix to remove interference to perform communication. Here, all groups of senders 10-1, 10-2, ..., 10-M and receivers 22-1, 22-2, ..., 22-K are N T and N R, respectively. Each transmitter 10-1, 10-2, ..., 10-M has an antenna and transmits a signal having d data streams by selecting one receiver 22 of a designated receiver group 20. Consider the situation.

In this communication situation, the received signal Y [ ki ] of the k-th receiver 22 of the i-th group represented by the N R x1 matrix may be expressed as follows.

Figure 112012098223821-pat00004

Here, X [i] is a transmission signal of the i-th sender 10 and is represented by a matrix of N T x1. X [i] = V [i] × d [i] , and V [i] is a transmission beamforming matrix represented by an N T × d matrix. Z [k] represented by an N [k] × 1 matrix is complex white Gaussian noise with an average of 0 and a variance of 1. The rail-rail fading channel H [i, ki ] represents a channel from the i-th sender 10 to the k-th receiver 22 of the i-th group, and is represented by an N R × N T matrix. The power of the received signal of each sender 10 is E [X 2 ] = P, and each data stream in the sender 10 has a power of P / d. In addition, α refers to the signal to interference ratio (SIR).

That is, the transmitter 10 may generate a random transmission beamforming matrix, generate a pilot signal based on the random transmission beamforming matrix, and transmit the generated pilot signal to the receiver 22. The receiver 22 receives the received signal as shown in Equation 1, and then the received signal of the k-th receiver 22 of the i-th group, which computes the reception beamforming matrix through a post-processing process, is defined as follows. .

Figure 112012098223821-pat00005

Here, U [k] means a reception beamforming matrix, and is generally calculated through singular value decomposition (SVD) operation, but may be calculated through various other methods. However, operations such as singular value decomposition are computation methods with high computational complexity. If such operations are included in the entire procedure, the overall process complexity is increased. However, each receiver 22 needs the reception beamforming matrix information such as U [k] for the attainable sum rate calculation, including interference for data transmission and reception with the transmitter 10, at the same calculation complexity. .

That is, the attainable sum transmission rate may be calculated based on the sum of the covariance matrix of the interference powers and the dispersion matrix of the designated signal. The sum of the dispersion matrices of the interference powers is expressed as follows.

Figure 112012098223821-pat00006

In addition, the variance matrix of the designated signal is as follows.

Figure 112012098223821-pat00007

The sum rate can be expressed as follows.

Figure 112012098223821-pat00008

That is, since the sum rate includes the reception beamforming matrix term of U [i, ki ], the singular value decomposition operation with high computational complexity must be performed several times to calculate the sum rate. On the system, it can be said that it is quite inefficient for all receivers 22 to do this.

Thus, an opportunistic interference alignment user selection technique can be used that selects a user based on the degree of interference that enters them. The opportunistic interference alignment user selection technique measures and returns the alignment information of the interference coming into the sender 10 through the following operation derived from the chordal distance function.

Figure 112012098223821-pat00009

Here, D 2 (A, B) means the crescent distance between the matrices A, B. L 1 and L 2 mean interference spaces from two unspecified transmitters 10 and L 1 and L 2 are orthogonal generator matrices generated from L 1 and L 2 , respectively. Each D 2 (L 1 , L 2 ) has a value imagined by any orthonormal matrix. Accordingly, each sender 10 receives a D 2 (L 1 , L 2 ) value from the receiver 22 of the receiver group 20 corresponding to it and has a minimum value (ie, the interference is aligned to the maximum). Select to send.

Then, only the receiver having the minimum value, that is, the receiver whose interference is maximally aligned, generates the reception beamforming matrix through singular value decomposition of the opportunistic beamforming technique. Among them, the reception beamforming matrix generated by the maximum signal-to-interference and noise technique can achieve the highest sum rate. The reception beamforming matrix may be expressed as follows.

Figure 112012098223821-pat00010

Here, v d [A] means a singular vector for the d-th largest singular value of the matrix A.

2 is a flowchart of an opportunistic interference alignment user selection technique. Referring to FIG. 2, first, the transmitter 10 generates a random beamforming matrix (S210). Then, the transmitter 10 generates a pilot signal based on the random beamforming matrix and transmits the pilot signal to each receiver 22 of the corresponding receiver group 20 (S220). The receiver receives local channel information based on the pilot signal (S230). Then, each receiver calculates the interference alignment information based on the crescent distance function as described above (S240). Then, the calculated value is returned to the sender 10 (S250). The sender 10 selects the receiver 22 that has returned the smallest value based on the interference alignment information received from each receiver 22 in the receiver group 20 corresponding to the transmitter 10 (S260). The selection signal is transmitted to the selected receiver (S270). The selected receiver generates a reception beamforming matrix capable of maximizing its transmission rate (S280). The aforementioned signal-to-interference and noise ratio maximization technique is one of the techniques that can maximize the transmission rate. When the sender 10 selects a specific receiver 22 from the receiver group 20 corresponding to the sender 10, the sender 10 performs communication in an interference channel situation in which the M-pair of the sender 10-receiver 22 exists ( S290).

However, since the opportunistic interference alignment user selection technique only considers the degree of alignment of the interference signal, there is a problem in that performance is degraded in various interference power environments and it is difficult to apply to three or more users. In addition, compared to the scheme that considers the power of the designated signal, there is a significant disadvantage in that the performance degradation of the sum rate occurs. Accordingly, the present invention performs a user selection based on the sum rate described above in order to overcome this problem, but provides an improved method for improving the overall efficiency by improving the complexity.

3 is a flowchart illustrating a receiver selection method in a multi-cell multiple input / output downlink network according to an embodiment of the present invention. As shown in FIG. 3, in the receiver selection method of the present invention, a receiver returns a largest value among a rate calculation step S310, a calculated value return step S320, and a sender that assumes a nonlinear receiver. Recipient selection step (S330) may be included. Through this, each receiver 22 selects the receiver 22 having the highest approximated data rate by calculating an approximation of the data rate assigned to it, so that the above-described opportunistic interference alignment user selection technique considers only the interference signal. Resolve the deterioration.

Referring to FIG. 3, in the rate calculation step S310, the receiver 22 approximates and calculates the sum rate that can be achieved as described above by assuming a nonlinear receiver. In other words, by assuming that the receiver is a non-linear receiver, it is possible to reduce the computational burden of each receiver 22 by approximating a portion having increased complexity in the sum rate calculation. The approximate sum transfer rate may be expressed as follows.

Figure 112012098223821-pat00011

The approximate sum rate is equal to or greater than the sum rate calculated through Equation 3, and the value is the same when the reception beamforming matrix is optimized. If the approximated sum transfer rate is further simplified, it may be expressed as follows.

Figure 112012098223821-pat00012

w is an approximate sum factor that is closer than C 'and is the factor that all receivers 22 should finally calculate.

Then, in the conveyance step S320, the receiver 22 transmits the calculated w factor to the sender 10.

The sender 10 returns the largest value among them in the receiver selection step S330 based on the approximate sum rate information received from each receiver 22 of the corresponding receiver group 20. Select. This is because a receiver who has returned the largest value can guarantee the best transmission state.

Subsequent steps are the same as described above, using Equation (7) to generate a reception beamforming matrix that can maximize its transmission rate. In this case, the reception beamforming matrix may be generated through a signal-to-interference and noise ratio maximization technique. Then, the transmitter 10 and the receiver 22 perform communication in the interference environment based on the reception beamforming matrix.

Device for transmitting rate related information for receiver selection in multi-cell multi-input downlink network

4 is a block diagram schematically illustrating a transmission rate related information transmitting apparatus 400 for receiver selection in a multi-cell multiple input / output downlink network according to an embodiment of the present invention. As shown in FIG. 4, a transmission rate related information transmitting apparatus 400 according to an embodiment of the present invention includes a receiver 410, a calculator 420, a transmitter 430, and a communication execution unit 440. can do.

Referring to FIG. 4, the receiver 410 receives a pilot signal from the transmitter 10. The pilot signal includes information related to the random transmission beamforming matrix. In addition, the pilot signal may include local channel information. In some cases, the local channel information is not included in the pilot signal, and may be separately received from the transmitter 10.

The calculator 420 extracts (or separately receives) local channel information from the received pilot signal to calculate approximate sum rate information. The approximated sum rate information can be calculated by approximating the receiver 22 itself as a non-linear receiver in the correct sum rate calculation formula. That is, the approximated sum rate information may be calculated based on the sum of the variance matrix of the interference signals of the other receivers existing in the current receiver group 20 and the variance matrix of the self-designated signal.

The transmitter 430 transmits the approximate sum rate information calculated through the calculator 420 to the sender 10.

Then, the sender selects the receiver 22 representing the largest value among at least one approximate sum rate information received from each receiver 22 and transmits a selection signal.

When receiving the selection signal from the transmitter 10, the communication execution unit 440 generates a reception beamforming matrix capable of maximizing a transmission rate using a singular value decomposition (SVD) technique, and based on this, Communication can be performed in an interfering channel situation. In this case, a signal-to-interference and noise ratio maximization technique may be used to generate a reception beamforming matrix capable of maximizing a transmission rate.

Receiver selection device in multi-cell multi-input downlink network

5 is a block diagram schematically illustrating an apparatus 500 for selecting a receiver in a multi-cell multiple input / output downlink network according to an embodiment of the present invention. As shown in FIG. 5, the receiver selection apparatus 500 according to an embodiment of the present invention includes a pilot signal transmitter 510, a sum rate information receiver 520, a selection signal transmitter 530, and a communication execution unit. 540 may include.

Referring to FIG. 5, the pilot signal transmitter 510 generates a pilot signal and transmits the pilot signal to the receiver 22. The pilot signal may be generated based on the random transmission beamforming matrix. The pilot signal transmitter 510 may generate a pilot signal including the local channel information and transmit the pilot signal to the receiver 22 or transmit the local channel information to the receiver 22 separately from the pilot signal.

The sum rate information receiving unit 520 receives approximate sum rate related information calculated from each receiver 22 in the corresponding group of recipients 20. As described above, the approximated sum rate related information is a sum rate calculated by assuming that the receiver 22 itself is a nonlinear receiver and approximated.

The selection signal transmitter 530 may include a configuration for selecting a receiver 22 to execute communication and a configuration for transmitting a selection signal. First, the selection signal transmitter 530 selects a receiver that transmits the largest value among at least one approximated sum rate related information received from each receiver 22 in the corresponding receiver group 20. This is because the receiver that sent the largest value is most likely to have the best rate. Then, the selection signal transmitter 530 transmits the selection signal to the selected receiver 22. The selection signal may be transmitted in flag format.

The communication execution unit 540 may receive the reception beamforming command information from the selected receiver 22 and execute communication in the interference channel situation based on the received beamforming command information. In this case, the receiver 22 may generate a reception beamforming matrix for maximizing its transmission rate and transmit it to the transmitter 10.

6 is a diagram illustrating a result of comparing a complexity of a receiver selection method and a conventional method in a multi-cell multi-input downlink network according to an embodiment of the present invention. This is a simulation result to help understand the effect of the receiver selection method of the present invention. In the simulations of FIGS. 6 and 7, in addition to the opportunistic user selection technique described herein, the minimum interference technique (MIN-INR) of the Opportunistic BeamForming User Selection (OBFUS) technique is conventionally employed. performances were compared. That is, the performance of the three techniques proposed by the present invention, Opportunistic Maximum Rate User Selection (OMRUS), Opportunistic Interference Alignment User Selection (OIAUS), and Minimal Interference (MIN-INR) Compared.

Referring to FIG. 6, the recipient selection method (OMRUS) according to one embodiment of the present invention requires some computational complexity than the opportunistic interference alignment user selection technique (OIAUS), but much more than the minimum interference technique (MIN-INR). You can see that it requires less computational complexity.

FIG. 7 illustrates a comparison between a receiver selection method and a conventional transmission rate in a multi-cell multi-input / output downlink network according to an embodiment of the present invention. The simulation shows that the antennas of all transmitters and receivers are N T with the interference-to-signal ratio α = 0.7 and the number of transmitters and receivers M = 3 and K = 10. = N R = 4 and the number of transmission data is d = 2, and the sum rate in each SNR interval is tested.

As shown in FIG. 7, the OMRUS according to an embodiment of the present invention exhibits a significantly higher sum rate than an opportunistic interference alignment user selection scheme (OIAUS) and a minimum interference scheme (MIN-INR). You can check it.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions as defined by the following claims It will be understood that various modifications and changes may be made thereto without departing from the spirit and scope of the invention.

Claims (16)

A method of transmitting rate related information to a sender for receiver selection in a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group, the method comprising:
Receiving a pilot signal from the sender;
Calculating approximate sum rate information assuming a non-linear receiver based on the received pilot signal;
And transmitting the approximated sum rate information to the sender. 10. The method of claim 1, further comprising transmitting the approximate sum rate information to the sender.
The method of claim 1, wherein the approximated sum rate information calculating step
And calculating the approximate sum rate information on the assumption that the receiver is a nonlinear receiver based on a sum of variance matrices of interference signals of other receivers present in the current receiver group and a variance matrix of self-designated signals. A method of transmitting rate related information for receiver selection in a multi-cell multi-input downlink network.
The method of claim 1, wherein the approximated sum rate information calculating step
Figure 112012098223821-pat00013
Where w is the approximate sum rate, I N is the unit matrix of N × N, Q [j, ki ] is the sum of the variance matrices of the interference signals of the k-th receiver in the i-th group, and Q [i, ki ] is calculating the approximate sum rate information using a distribution matrix of a designated signal for a k-th receiver in an i-th group). Transmission rate related information.
The method of claim 1,
The sender selects a receiver that transmits the largest value among at least one of the approximated sum rate information received from a receiver belonging to a receiver group corresponding to the sender, and transmits a selection signal. A method of transmitting rate related information for receiver selection in a link network.
5. The method of claim 4,
When receiving the selection signal from the sender, by using a singular value decomposition (SVD) technique to generate a reception beamforming matrix that can maximize the transmission rate and performing communication in the interference channel situation with the sender The transmission rate related information transmission method for the receiver selection in a multi-cell multi-input and downlink network further comprising.
The method of claim 1,
And the pilot signal includes local channel knowledge. 10. The method of claim 1, wherein the pilot signal comprises local channel knowledge.
An apparatus for transmitting rate related information to a sender for receiver selection in a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group, the apparatus comprising:
A receiver which receives a pilot signal from the transmitter;
A calculator calculating an approximate sum rate information on the assumption of a nonlinear receiver based on the received pilot signal; And
And a transmitter for transmitting the approximate sum rate information to the sender.
A method of selecting a receiver in a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group, the method comprising:
Transmitting a pilot signal to each recipient;
Receiving at least one approximate sum rate information calculated on the assumption of a nonlinear receiver from at least one receiver belonging to a corresponding receiver group;
And selecting a receiver having transmitted the largest value among the received at least one approximated sum rate information and transmitting a selection signal.
The method of claim 8,
The approximate sum rate information is
Figure 112012098223821-pat00014
Where w is the approximate sum rate, I N is the unit matrix of N × N, Q [j, ki ] is the variance matrix of the interference signal of the k-th receiver in the i-th group, and Q [i, ki ] is the i-th Means a distribution matrix of a designation signal for a k-th receiver in a group).
The method of claim 8,
Receiving reception beamforming matrix information from the selected receiver to perform communication in an interference channel situation.
The method of claim 8,
Generating a random transmit beamforming matrix;
And generating said pilot signal based on said random beamforming matrix.
An apparatus for selecting a receiver in a multi-cell multi-input downlink network having a plurality of sender groups and a receiver group, the apparatus comprising:
A pilot signal transmitter for transmitting a pilot signal to each receiver;
A sum rate information receiver configured to receive at least one approximated sum rate information calculated on the assumption of a nonlinear receiver from at least one receiver belonging to a corresponding receiver group; And
And a selection signal transmitter for transmitting a selection signal by selecting a receiver having transmitted the largest value among the received at least one approximated sum transmission rate information.
A system for recipient selection in a multi-cell multi-input downlink network having multiple sender groups and recipient groups,
A receiver receiving a pilot signal from a transmitter, calculating approximate sum rate information assuming a nonlinear receiver based on the received pilot signal, and transmitting the approximated sum rate information to the sender; And
Transmitting the pilot signal to each receiver, receiving at least one approximated sum rate information from at least one receiver belonging to a corresponding group of recipients, and receiving the at least one approximated sum rate information A receiver selection system in a multi-cell multiple input / output downlink network, comprising: a sender for selecting a receiver having transmitted a large value and transmitting a selection signal.
The method of claim 13, wherein the recipient is
The approximate sum rate information is calculated based on the sum of the variance matrix of the interference signals of the other receivers present in the current receiver group and the variance matrix of the self-designated signal. Recipient Selection System in Downlink Networks.
The method of claim 13, wherein the recipient is
Figure 112012098223821-pat00015
Where w is the approximate sum rate, I N is the unit matrix of N × N, Q [j, ki ] is the variance matrix of the interference signal of the k-th receiver in the i-th group, and Q [i, ki ] is the i-th Means approximation sum rate information using a distribution matrix of a designated signal for a k-th receiver in a group.
The method of claim 13, wherein the recipient is
When receiving the selection signal from the sender, by using a Singular Value Decomposition (SVD) technique to generate a reception beamforming matrix that can maximize the transmission rate to perform communication in the interference channel situation with the sender A receiver selection system in a multi-cell multi-input downlink network.
KR1020120135450A 2012-11-27 2012-11-27 Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network KR101323378B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020120135450A KR101323378B1 (en) 2012-11-27 2012-11-27 Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020120135450A KR101323378B1 (en) 2012-11-27 2012-11-27 Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network

Publications (1)

Publication Number Publication Date
KR101323378B1 true KR101323378B1 (en) 2013-10-28

Family

ID=49639567

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020120135450A KR101323378B1 (en) 2012-11-27 2012-11-27 Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network

Country Status (1)

Country Link
KR (1) KR101323378B1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101632825B1 (en) * 2015-01-21 2016-06-23 한국과학기술원 Method and apparatus for receiving of uplink supporting mobility in large-scale antenna system
CN108234101A (en) * 2018-01-11 2018-06-29 郑州航空工业管理学院 Efficiency maximizes pilot signal design method and large-scale multi-antenna system

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20090038090A (en) * 2007-10-15 2009-04-20 삼성전자주식회사 Apparatus and method for calculation channel information for multiple user mode in multiple inpute multiple output wireless communication system
KR20100138126A (en) * 2009-06-24 2010-12-31 주식회사 케이티 Method for selecting data transmission mode in distributed antenna system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20090038090A (en) * 2007-10-15 2009-04-20 삼성전자주식회사 Apparatus and method for calculation channel information for multiple user mode in multiple inpute multiple output wireless communication system
KR20100138126A (en) * 2009-06-24 2010-12-31 주식회사 케이티 Method for selecting data transmission mode in distributed antenna system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101632825B1 (en) * 2015-01-21 2016-06-23 한국과학기술원 Method and apparatus for receiving of uplink supporting mobility in large-scale antenna system
CN108234101A (en) * 2018-01-11 2018-06-29 郑州航空工业管理学院 Efficiency maximizes pilot signal design method and large-scale multi-antenna system

Similar Documents

Publication Publication Date Title
CN107483088B (en) Large-scale MIMO robust precoding transmission method
US8498193B2 (en) Method for selection of an optimized number of subscribers in mobile radio systems
KR101507088B1 (en) Aparatus and method for uplink baemforming and space-division multiple access in multi-input multi-output wireless communication systems
CN103220024B (en) A kind of multi-user matches the beam form-endowing method of virtual MIMO system
CN103763782B (en) Dispatching method for MU-MIMO down link based on fairness related to weighting users
CN101378277A (en) Method for pre-encoding and scheduling multi-user, and base station for implementing the method
Vaigandla et al. Analysis of MIMO-OFDM: Effect of Mutual Coupling, Frequency Response, SNR and Channel Capacity
CN101277172A (en) Method, apparatus and system for generating precoding matrix
JP2012533952A (en) Precoding method for transmitter of MU-MIMO communication system
EP3403336A1 (en) Communication device and methods thereof
KR20150134520A (en) Apparatus for processing transmission/reception signal for interference alignment in a mu-mimo interference broadcasting channel and method thereof
CN110166088A (en) The power control algorithm without cell mimo system of customer-centric
CN102857278B (en) Resource allocation method
Dong et al. Improved joint antenna selection and user scheduling for massive MIMO systems
JP2009153139A (en) Pre-coding processing method and apparatus for mimo downlink, and base station
CN102833038B (en) Downlink multi-business collaboration pre-coding method of multi-cell multicast MIMO (multiple input multiple output) mobile communication system
Li et al. On channel reciprocity to activate uplink channel training for downlink wireless transmission in tactile internet applications
JP2008236066A (en) Transmission method and apparatus for spatial multiplex transmission
Hammarwall et al. Utilizing the spatial information provided by channel norm feedback in SDMA systems
KR101323378B1 (en) Transmission rate related information transmission apparatus and method for receiver selection in multi cell mimo downlink network, and receiver selection apparatus, method and system in multi cell mimo downlink network
CN110212957B (en) Signal-to-leakage-and-noise-ratio-based MU-MIMO system user scheduling method
CN101989867B (en) Cooperative communication method and system, base station and mobile terminal device
CN102195697B (en) Multi-input multi-output beamforming system and data sending method thereof
Fan et al. Spatial multi-user pairing for uplink virtual-MIMO systems with linear receiver
EP3759831A1 (en) Method to estimate snr for mu-mimo based on channel orthogonality

Legal Events

Date Code Title Description
A201 Request for examination
E701 Decision to grant or registration of patent right
GRNT Written decision to grant
FPAY Annual fee payment

Payment date: 20160928

Year of fee payment: 4

FPAY Annual fee payment

Payment date: 20171016

Year of fee payment: 5

LAPS Lapse due to unpaid annual fee