CN107276698B - Millimeter wave wireless network neighbor discovery method and device - Google Patents
Millimeter wave wireless network neighbor discovery method and device Download PDFInfo
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- CN107276698B CN107276698B CN201710513790.7A CN201710513790A CN107276698B CN 107276698 B CN107276698 B CN 107276698B CN 201710513790 A CN201710513790 A CN 201710513790A CN 107276698 B CN107276698 B CN 107276698B
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Abstract
The embodiment of the invention provides a millimeter wave wireless network neighbor discovery method and a millimeter wave wireless network neighbor discovery device, wherein the method comprises the steps of decoding a beacon of a first target beam after monitoring the first target beam, extracting channel state information of the beacon of the first target beam if the beacon of the first target beam cannot be successfully decoded, and accumulating the channel state information of the beacon of the first target beam to space channel state information; obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information; performing beam monitoring along the direction of the optimal estimated signal arrival angle; decoding a beacon of a second target beam after monitoring the second target beam, wherein the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival; by applying the scheme provided by the embodiment of the application, the neighbor discovery is realized in the wireless network.
Description
Technical Field
The invention relates to the technical field of wireless networks, in particular to a millimeter wave wireless network neighbor discovery method and device.
Background
Mobile network traffic is increasing dramatically due to the unprecedented growth in mobile device and mobile application bandwidth demand, and industry predicts that mobile traffic demand will increase 1000 times from 2012 to 2020. Millimeter wave communication is generally considered the last resort to address the problem of explosive growth of traffic, e.g., 60GHz millimeter wave communication. The two recent IEEE 60GHz MAC/PHY standards, 802.11ad and 802.15.3c, have been approved and will support a variety of new wireless very high speed applications such as uncompressed high definition video streaming, instant file synchronization, and wireless extensions.
The conventional Neighbor Discovery (ND) is implemented in WiFi or cellular networks as follows: the network Access Point (AP) broadcasts beams periodically, and after the client terminal arranged in the range of the AP recognizes the beacon of the beam, the client terminal can know the AP information and request to Access the AP. However, the solution is only for the traditional WiFi or cellular network, and cannot be applied to the millimeter wave high-speed wireless network, such as a 60GHz wireless network.
Disclosure of Invention
The embodiment of the invention aims to provide a method and a device for discovering neighbors of a millimeter wave wireless network, which are used for realizing neighbor discovery in a millimeter wave high-speed network, and the specific technical scheme is as follows:
after monitoring a first target beam, decoding a beacon of the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array;
if the beacon of the first target beam cannot be successfully decoded, extracting the channel state information of the beacon of the first target beam, and accumulating the channel state information of the beacon of the first target beam to the spatial channel state information;
obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
performing beam monitoring along the direction of the optimal estimated signal arrival angle;
decoding a beacon of a second target beam after monitoring the second target beam, wherein the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival;
if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful;
if the beacon of the second target beam cannot be successfully decoded, storing the second target beam in a beam set for storing an optimal beam;
if the beacon of the first beam can be successfully decoded, neighbor discovery is successful.
Further, after the storing the second beam in the beam set for storing the best beam, the method further comprises:
obtaining a distance between each beam in a second beam set and each beam in the first beam set, wherein the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
determining a beam corresponding to the largest distance in the second beam set in the obtained distances as a third beam;
and decoding the beacon of the third beam, and successfully discovering the neighbor.
Further, before the decoding of the beacon of the third beam and the success of neighbor discovery, the method further includes:
judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value;
if so, executing the steps of decoding the beacon of the third beam and successfully discovering the neighbor;
if not, continuing to monitor the beams supported by the antenna array, and returning to execute the step of decoding the beacon of the first target beam after monitoring the first target beam.
Further, the extracting channel state information of the beacon of the first target beam includes:
and extracting a lead code of the beacon of the first target beam, decoding the lead code, and obtaining the channel state information of the first target beacon.
Further, the preamble is composed of a short training field composed of X M-golay sequences and a channel estimation field composed of Y N-golay sequences, wherein X, Y are numbers of the M-golay sequences and the N-golay sequences, respectively, and M, N is a bit number of the golay sequences.
Further, the obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information includes:
obtaining theoretical channel state information according to a preset channel model, wherein the preset channel model is as follows: a channel model constructed using beamforming of the antenna array;
establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
and solving the target model to obtain the optimal estimated signal arrival angle.
Further, solving the target model includes:
and solving the target model by using a convex optimization algorithm.
A millimeter wave wireless network neighbor discovery device comprises an accumulation spatial channel module, a prediction optimal monitoring beam module and a beam module with the largest distance:
a first decoding module, configured to decode a beacon of a first target beam after monitoring the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array; if the beacon of the first beam can be successfully decoded, the neighbor finds that the beacon of the first target beam can not be successfully decoded, and a channel extraction module is triggered;
the channel extracting module is configured to extract channel state information of a beacon of the first target beam, and accumulate the channel state information of the beacon of the first target beam to spatial channel state information;
the optimal estimated signal arrival angle predicting module is used for obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
a beam monitoring module for predicting the optimal monitoring beam, which is used for performing beam monitoring along the direction of the optimal estimated signal arrival angle;
a second decoding module, configured to decode a beacon of a second target beam after monitoring the second target beam, where the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival; if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful; triggering a beam set module if the beacon of the second target beam cannot be successfully decoded;
the beam set module is configured to store the second target beam in a beam set used for storing an optimal beam.
Further, the apparatus further comprises:
a distance calculating module, configured to obtain a distance between each beam in a second beam set and each beam in the first beam set, where the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
a comparing module, configured to determine, as a third beam, a beam corresponding to a maximum distance in the second beam set among the obtained distances;
and the third decoding module is used for decoding the beacon of the third beam, and the neighbor discovery is successful.
Further, the apparatus further comprises:
the judging module is used for judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value or not; if so, executing the steps of decoding the beacon of the third beam and successfully discovering the neighbor; if not, triggering a monitoring beam module;
and the beam monitoring module is used for continuously monitoring the beams supported by the antenna array and returning to execute the step of decoding the beacon of the first target beam after the first target beam is monitored.
Further, the channel extracting module includes:
and the channel state information acquisition submodule is used for extracting the lead code of the beacon of the first target beam, decoding the lead code and acquiring the channel state information of the first target beacon.
Further, the module for predicting the best estimated signal arrival angle comprises:
the theoretical channel state information submodule is used for obtaining theoretical channel state information according to a preset channel model, wherein the preset channel model is as follows: a channel model constructed using beamforming of the antenna array;
the target model submodule is used for establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
and the optimal estimated signal arrival angle obtaining submodule is used for solving the target model to obtain an optimal estimated signal arrival angle.
In yet another aspect of the present invention, there is also provided a computer-readable storage medium having stored therein instructions, which when run on a computer, cause the computer to perform any one of the above-described millimeter wave wireless network neighbor discovery methods.
In yet another aspect of the present invention, the present invention also provides a computer program product containing instructions, which when run on a computer, causes the computer to execute any one of the above-mentioned millimeter wave wireless network neighbor discovery methods.
According to the millimeter wave wireless network neighbor discovery method and device provided by the embodiment of the invention, the optimal estimated signal arrival angle can be obtained according to the preset channel model and the spatial channel state information; performing beam monitoring along the direction of the optimal estimated signal arrival angle; and after monitoring the second target wave beam, decoding the beacon of the second target wave beam, and further realizing neighbor discovery in the wireless network. Of course, it is not necessary for any product or method of practicing the invention to achieve all of the above-described advantages at the same time.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a flowchart of a first millimeter wave wireless network neighbor discovery method according to an embodiment of the present disclosure;
fig. 2 is a flowchart of a second millimeter wave wireless network neighbor discovery method according to an embodiment of the present disclosure;
fig. 3 is a schematic structural diagram of a millimeter wave wireless network neighbor discovery apparatus according to an embodiment of the present application
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a first millimeter wave wireless network neighbor discovery method provided in an embodiment of the present application, where the method includes:
s101, after monitoring a first target beam, decoding a beacon of the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array; if the beacon of the first beam can be successfully decoded, the neighbor discovery is successful; if the beacon of the first target beam cannot be successfully decoded, executing S102;
the execution main body of the embodiment of the application can be understood as a client, and after the client accesses a mobile communication network, neighbor discovery is required to be performed for realizing network communication.
Wherein the above-mentioned beam is emitted by an antenna array, alternatively, the beam (wave beam) may be an electromagnetic wave emitted by a 60GHz radio antenna array, shaped in space as a light beam emitted by a flashlight to the dark. Mainly comprises a global beam, a point-shaped beam and a shaped beam. They are shaped by the transmitting antenna, but the beam may be emitted by an antenna array based on other mm-wave wireless networks, such as 28GHz,73GHz wireless networks.
The decoding is a process of restoring a digital code to its contents or converting an electric pulse signal, an optical signal, a radio wave, etc. into information, data, etc. represented by it in a specific way.
It should be noted that the above-mentioned non-decodable may be understood as that the receiver fails to convert the beacon (signal) form.
S102, extracting channel state information of the beacon of the first target beam, and accumulating the channel state information of the beacon of the first target beam to spatial channel state information;
wherein, the channels (information channels) are transmission media of signals and can be divided into two types of wired channels and wireless channels; that is, a channel refers to a signal path provided by a wired or wireless line.
The channel state information is: channel properties of the communication link. It describes the fading factor of the signal on each transmission path, i.e. the value of each element in the channel gain matrix H, such as signal Scattering (Scattering), fading or fading, distance fading (power fading), and other information. The CSI may adapt the communication system to the current channel conditions, providing a guarantee for high reliability and high rate communication in a multi-antenna system.
The idle channel state information includes signal strength and phase in each direction of space.
The accumulated spatial channel state information may be understood as: the client stores and accumulates the signal strength and the phase of the sequentially received non-decodable beacons in each direction of the space one by one to obtain the space channel state information accumulated by the non-decodable beacons, and the channel state information is extracted from the non-decodable beacons based on the high redundancy protection of the beacon lead codes by 802.11 ad.
Specifically, one embodiment of the above method for extracting the channel state information of the beacon of the first target beam is as follows:
and extracting a lead code of the beacon of the first target beam, decoding the lead code, and obtaining the channel state information of the first target beacon.
Specifically, the beacon preamble is: the channel estimation method comprises a Short Training Field (STF) consisting of X M-Gaoley sequences and a Channel Estimation Field (CEF) consisting of Y N-Gaoley sequences, wherein the short training field consists of X M-Gaoley sequences and the channel estimation field consists of Y N-Gaoley sequences, X, Y is the number of the M-Gaoley sequences and the N-Gaoley sequences respectively, and M, N is the number of bits of the Gaoley sequences.
The beacon preamble is a standard preamble, and is composed of a Short Training Field (STF) composed of 40 128-golay sequences and a Channel Estimation Field (CEF) composed of 9 128-golay sequences.
STF and CEF are both low order but robust
(Binary Phase Shift Keying ) configured to detect the presence of a beacon and perform time/frequency synchronization; CEF is used to estimate Channel State Information (CSI), where robust refers to being more resistant to interference and noise than other normally loaded data. Because the payload (including the header and data of the packet) is modulated using a higher order constellation (up to 16-QAM) in combination with Direct Sequence Spread Spectrum (DSSS) or Orthogonal Frequency Division Multiplexing (OFDM), wherein a DSSS module payload is loaded with one of the data packets
(L ow-dense Parity-check) encodes a 32-fold spreading factor of the protection STF and CEF are both more robust than DSSS and OFDM, so the beacon preamble can be used to extract the decoded spatial channel state information.
For example, if there are 1152 symbols for estimating CSI in 9 × and 64 symbols for decoding each bit of the payload data in 32 ×, it can be seen that the SNR (signal-to-NOISE RATIO) of the estimated CSI is lower than the SNR of the estimated payload data
That is, given an RSS (received signal Strength) threshold of decoded payload data bits of-78 dBm, the CSI extraction threshold THCSI may be as low as-78-12.55-90.55 dBm.
S103, obtaining an optimal estimated signal arrival angle according to a preset channel model and the space channel state information;
the arrival angle of the signal is an included angle between the arrival direction of the signal and a space coordinate axis;
in particular, the method comprises the following steps of,
obtaining theoretical channel state information according to a preset channel model, wherein the preset channel model is as follows: a channel model constructed using beamforming of the antenna array;
establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
and solving the target model to obtain the optimal estimated signal arrival angle.
It should be noted that, when receiving signals, the 802.11ad client performs codebook-based beamforming construction using an antenna array, the signal along each spatial direction is the product of the spatial channel response and the gain of the antenna along that direction, therefore, to generate the u-th beam, a series of beam weights are applied to the antenna elements, NRThe beam generation gain of the linear antenna array with the elements in any space direction theta (n), namely a channel model A (u, n), is as follows:
where d is the spacing of the antenna elements, λ is the carrier wavelength, U ∈ [1, U]U is the total number of beams, w (U, i) is the weight vector corresponding to the U-th beam and the i-th antenna element, NRIs the number of elements of the linear antenna array, j is an imaginary number, exp (-) is e(·)I.e. e(·)Is an exponential function with a base number e, N is the number of spatial channels, N ∈ [1, …, N]N is the total number of the space channels, and N and N are positive integers;
obtaining theoretical channel state information according to the channel model
Where x (-) is a continuous spatial channel response function for all spatial angles.
Establishing a target model of the channel state according to the theoretical channel state information, the channel state information and the channel space constraint condition; the specific process is as follows:
the channel of the u-th beam is measured and denoted as hms(u) obtaining a constraint equation according to the theoretical channel state information as follows:
the client obtains all P CSI measurements H along a series of beam Φ directionsmsIs recorded as Hms＝{hms(1),…,hms(P) }, the measurement results are:
AΦ,Nx＝Hms
AΦ,Ngenerating a matrix for the beam; hmsA matrix formed by the channel measurement results; p is the CSI measurement HmsX is a vector formed by x, and x is the continuous spatial channel response of all spatial angles.
The above implementation of the present embodiment is now defined as compressed sensing based beam prediction (CSBP).
It is worth mentioning that in theory the above equation still has a high degree of uncertainty since x is the continuous spatial channel response for all spatial angles, but because of the inherent sparsity for the actual 60GHz channel, it can be passed through a matrix H composed from channel measurementsmsAnd a beam forming matrix AΦ,N recovers a small amount of dominant space angles, namely a recovery problem is treated as an optimization problem by applying a compressed sensing theory, and then a target model with a channel state is as follows:
min‖x‖1
s.t.AΦ,Nx＝Hms
wherein |1Is a first order norm, s.t. represents a constraint condition;
wherein the objective model of the channel state is modeled using a convex optimization algorithmSolving to obtain the optimal solution of the target model, wherein the optimal solution is the optimal estimation signal arrival angle
It should be noted that the objective model may also be solved by using a method such as a genetic algorithm, and the present invention is not limited to the convex optimization algorithm.
S104, performing beam monitoring along the direction of the optimal estimated signal arrival angle;
according to the best estimated signal arrival angle
I.e. the best solution, the client can find the best listening beam
I.e. the beam that produces the strongest channel when combining antenna gain and channel gain:
wherein U is the number of beams,
the best estimated signal arrival angle for the nth direction;
s105, after monitoring a second target beam, decoding a beacon of the second target beam, where the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival; if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful; if the beacon of the second target beam cannot be successfully decoded, executing S106;
the above-mentioned decoding of the beacon of the second target beam, that is, the decoding of the beacon of the beam monitored in the direction of the best estimated signal arrival angle. I.e., the client may control the beam direction selection, thereby increasing the likelihood of quickly decoding the AP beam and completing neighbor discovery.
If the beacon of the beam monitored in the direction of the best estimated signal arrival angle can be decoded successfully, the neighbor considers that the discovery is successful.
S106, storing the second target beam in a beam set for storing the optimal beam.
The stored optimal beam is a beam monitored in the direction of the angle of arrival of the optimal estimated signal.
Therefore, according to the channel model and the channel state information of the beam beacon, the optimal estimated signal arrival angle is obtained, the optimal monitored beam is found according to the optimal estimated signal arrival angle, the beacon of the optimal monitored beam is decoded, and then neighbor discovery is achieved in the wireless network.
After storing the second beam in the beam set for storing the best beam, a manner that can be further implemented is:
obtaining a distance between each beam in a second beam set and each beam in the first beam set, wherein the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
determining a beam corresponding to the largest distance in the second beam set in the obtained distances as a third beam;
and decoding the beacon of the third beam, and successfully discovering the neighbor.
Wherein, the third beam may be understood as searching for a beam having the maximum orthogonality with the beam set of the currently attempted decoding, the currently attempted decoding beam being the beam set formed by the second target beam, and the beam direction of the maximum orthogonality refers to the beam direction having the angle between the second target beam direction and the beam direction in the beam set Φ closest to 90 °. That is, to avoid the CSBP getting stuck in an overfitting infinite loop and failing to decode, it is necessary to listen to a beam that is the largest distance (i.e., most orthogonal) from the previously tried set of beams; based on the purpose, the overfitting optimization of the CSBP can be jumped out with the maximum probability.
In particular, the method comprises the following steps of,
when the number of channel measurements is insufficient, compressed sensing optimization may over-fit the channel characteristics x, the best listening beam predicted from a compressed sensing based beam prediction (CSBP) undecodable prediction
Fall into the set of beams Φ that the client has attempted to query.
In view of this, a Maximum distance based beam prediction (MDBP) is proposed, that is, a beam direction having the Maximum orthogonality with the currently tried beam set is found, where the beam direction having the Maximum orthogonality refers to a beam direction having an angle between the best listening beam, that is, the second target beam direction, and the beam direction in the beam set Φ closest to 90 °, so that based on the distance-maximized beam, the Maximum amount of information can be added to the channel characteristics, thereby helping to quickly converge based on the distance and reduce the ND delay.
To determine orthogonality between beams, a distance matrix is designed in the MDBP. Since the actual beam generated by the antenna array is different from the assumed ideal isomorphic fan beam, the coverage area and beam intensity of the actual beam are heterogeneous. Thus, in MDBP, the distance Δ between beam i and beam ji,jIs defined as:
Δi,j＝||A(i,:)-A(j,:)||1
since the difference between the amplitude and the phase is taken into account, the difference between beams of irregular shapes is reflected, thereby obtaining the distance delta between the beam i and the beam set phi which attempts to search for the optimal listening beam formationi,ΦComprises the following steps:
where i is a beam generated by the antenna array, Φ is a beam set, Φ ═ 1, …, j, … U }
The beam with the largest distance is selected from all the acquired distances.
Specifically, the beam having the largest value among the distances between the beam i and the beam set Φ is selected
Comprises the following steps:
in a clear view of the above, it is known that,
the tried beams in the relative beam set phi are the most orthogonal, so that the monitoring direction of the MDBP control client is obtained
On the beam, Δi,ΦIs a shorthand for Δ (i, Φ).
It is worth mentioning that: MDBP incorporates a "metric" measuring the maximum set of distances between beams and beam sets to guide the selection of the next beam direction that is likely to provide the most orthogonal channel information, thus avoiding over-saturation of CSBP. Neighbor discovery preserves the beacon mechanisms of the 802.11ad physical and MAC layers, and is compatible with the 802.11ad standard.
Signal strength of the beam at the maximum distance
And a set signal strength threshold
Make a comparison if
Greater than or equal to
Obtaining the wave beam with the optimal distance, decoding the beacon of the wave beam with the optimal distance, and successfully finding the neighbor; otherwise, returning to execute the second target wave beam after monitoring the first target wave beamAnd a step of decoding the beacon of a target beam until the beam with the optimal distance is obtained, so that the neighbor discovery delay in the millimeter wave directed network is further reduced, and the client can be connected to the network more quickly.
After determining, as the third beam, the beam corresponding to the maximum distance in the obtained distances in the second beam set, another further implementation manner may be that:
obtaining a distance between each beam in a second beam set and each beam in the first beam set, wherein the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
determining a beam corresponding to the largest distance in the second beam set in the obtained distances as a third beam;
judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value;
if so, executing the steps of decoding the beacon of the third beam and successfully discovering the neighbor;
if not, continuing to monitor the beams supported by the antenna array, and returning to execute the step of decoding the beacon of the first target beam after monitoring the first target beam.
And decoding the beacon of the third beam, and successfully discovering the neighbor.
Based on the foregoing specific implementation manner, in another specific implementation manner of the present application, referring to fig. 2, a flow diagram of a second millimeter wave wireless network neighbor discovery method is provided, where the method includes:
s201, after monitoring a first target beam, decoding a beacon of the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array; if the beacon of the first beam can be successfully decoded, the neighbor discovery is successful, and if the beacon of the first target beam cannot be successfully decoded, the step S202 is executed;
s202, extracting channel state information of the beacon of the first target beam, and accumulating the channel state information of the beacon of the first target beam to spatial channel state information;
s203, obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
s204, establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
s205, solving the target model to obtain an optimal estimated signal arrival angle;
s206, performing beam monitoring along the direction of the optimal estimated signal arrival angle;
s207, after monitoring a second target beam, decoding a beacon of the second target beam, where the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival; if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful; if the beacon of the second target beam cannot be successfully decoded, executing S208;
s208, storing the second target beam in a beam set for storing an optimal beam;
s209, obtaining a distance between each beam in a second beam set and each beam in the first beam set, where the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
s210, determining a beam corresponding to the maximum distance in the second beam set in the obtained distances as a third beam;
s211, judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value; if yes, decoding the beacon of the third beam, and if not, executing S212;
s212, continue to monitor the beams supported by the antenna array, and return to performing S201.
The present embodiment predicts the optimal beam direction using the obtained channel state information and channel model by accumulating spatial channel information using an undecodable beacon; and acquiring the beam with the maximum distance according to the acquired optimal monitoring beam, and quickly and accurately realizing neighbor discovery in the wireless network.
Corresponding to the millimeter wave wireless network neighbor discovery, the embodiment of the application also provides a millimeter wave wireless network neighbor discovery device.
Fig. 3 is a schematic structural diagram of a millimeter wave wireless network neighbor discovery apparatus provided in an embodiment of the present application, where the apparatus includes:
a first decoding module 301, a channel extracting module 302, an optimal estimated signal arrival angle predicting module 303, an optimal listening beam predicting module 304, a second decoding module 305, and a beam set module 306:
a first decoding module 301, configured to decode a beacon of a first target beam after monitoring the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array; if the beacon of the first beam can be successfully decoded, the neighbor discovery is successful, and if the beacon of the first target beam cannot be successfully decoded, the channel extraction module 302 is triggered;
the extract channel module 302 is configured to extract channel state information of a beacon of the first target beam, and accumulate the channel state information of the beacon of the first target beam into spatial channel state information;
an optimal estimated signal arrival angle predicting module 303, configured to obtain an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
a predicted optimal listening beam module 304, configured to perform beam listening in a direction along the optimal estimated signal arrival angle;
a second decoding module 305, configured to decode a beacon of a second target beam after monitoring the second target beam, where the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival; if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful; triggering the beam set module 306 if the beacon of the second target beam cannot be successfully decoded;
the beam set module 306 is configured to store the second target beam in a beam set for storing an optimal beam.
In particular, the method comprises the following steps of,
the device further comprises:
a distance calculating module, configured to obtain a distance between each beam in a second beam set and each beam in the first beam set, where the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
a comparing module, configured to determine, as a third beam, a beam corresponding to a maximum distance in the second beam set among the obtained distances;
and the third decoding module is used for decoding the beacon of the third beam, and the neighbor discovery is successful.
The judging module is used for judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value or not; if so, executing the steps of decoding the beacon of the third beam and successfully discovering the neighbor; triggering a monitoring beam module, if not, triggering the monitoring beam module;
and the beam monitoring module is used for continuously monitoring the beams supported by the antenna array and returning to execute the step of decoding the beacon of the first target beam after the first target beam is monitored.
The channel extracting module 302 includes:
and the channel state information acquisition submodule is used for extracting the lead code of the beacon of the first target beam, decoding the lead code and acquiring the channel state information of the first target beacon.
The module 303 for predicting an optimal estimated signal arrival angle comprises:
the theoretical channel state information submodule is used for obtaining theoretical channel state information according to a preset channel model, wherein the preset channel model is as follows: a channel model constructed using beamforming of the antenna array;
the target model submodule is used for establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
and the optimal estimated signal arrival angle obtaining submodule is used for solving the target model to obtain an optimal estimated signal arrival angle.
The apparatus of the present embodiment predicts the optimal beam direction using the obtained channel state information by accumulating spatial channel information using an undecodable beacon; and acquiring the beam with the maximum distance according to the acquired optimal monitoring beam, and quickly and accurately realizing neighbor discovery in the wireless network.
The embodiment of the invention also provides electronic equipment which comprises a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory complete mutual communication through the communication bus,
a memory for storing a computer program;
the processor is used for realizing the following steps when executing the program stored in the memory:
after monitoring a first target beam, decoding a beacon of the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array;
if the beacon of the first target beam cannot be successfully decoded, extracting the channel state information of the beacon of the first target beam, and accumulating the channel state information of the beacon of the first target beam to the spatial channel state information;
obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
performing beam monitoring along the direction of the optimal estimated signal arrival angle;
decoding a beacon of a second target beam after monitoring the second target beam, wherein the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival;
if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful;
if the beacon of the second target beam cannot be successfully decoded, storing the second target beam in a beam set for storing an optimal beam;
if the beacon of the first beam can be successfully decoded, neighbor discovery is successful.
Therefore, the electronic device provided by this embodiment can obtain the best estimated signal arrival angle according to the channel model and the channel state information of the beam beacon, find the best monitored beam according to the best estimated signal arrival angle, decode the beacon of the best monitored beam, and further implement neighbor discovery in the wireless network.
The implementation of the related neighbor discovery method is the same as the neighbor discovery method provided in the foregoing method embodiment, and is not described here again.
The communication bus mentioned in the electronic device may be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The communication bus may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one thick line is shown, but this does not mean that there is only one bus or one type of bus.
The communication interface is used for communication between the electronic equipment and other equipment.
The Memory may include a Random Access Memory (RAM) or a Non-Volatile Memory (NVM), such as at least one disk Memory. Optionally, the memory may also be at least one memory device located remotely from the processor.
The Processor may be a general-purpose Processor, including a Central Processing Unit (CPU), a Network Processor (NP), and the like; but may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic device, discrete hardware component.
A computer-readable storage medium having a computer program stored therein, which when executed by a processor, performs the steps of:
after monitoring a first target beam, decoding a beacon of the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array;
if the beacon of the first target beam cannot be successfully decoded, extracting the channel state information of the beacon of the first target beam, and accumulating the channel state information of the beacon of the first target beam to the spatial channel state information;
obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
performing beam monitoring along the direction of the optimal estimated signal arrival angle;
decoding a beacon of a second target beam after monitoring the second target beam, wherein the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival;
if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful;
if the beacon of the second target beam cannot be successfully decoded, storing the second target beam in a beam set for storing an optimal beam;
if the beacon of the first beam can be successfully decoded, neighbor discovery is successful.
It can be seen that, when the application program stored in the computer-readable storage medium provided in this embodiment is executed, the best estimated signal arrival angle can be obtained according to the channel model and the channel state information of the beam beacon, the best monitored beam is found according to the best estimated signal arrival angle, the beacon of the best monitored beam is decoded, and then the neighbor discovery is realized in the wireless network.
The implementation of the related neighbor discovery method is the same as the neighbor discovery method provided in the foregoing method embodiment, and is not described here again.
It is thus noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the embodiments of the apparatus, the electronic device, and the computer-readable storage medium, since they are substantially similar to the embodiments of the method, the description is simple, and for the relevant points, reference may be made to the partial description of the embodiments of the method.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.
Claims (12)
1. A millimeter wave wireless network neighbor discovery method is characterized by comprising the following steps:
after monitoring a first target beam, decoding a beacon of the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array;
if the beacon of the first target beam cannot be successfully decoded, extracting the channel state information of the beacon of the first target beam, and accumulating the channel state information of the beacon of the first target beam to the spatial channel state information;
obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
performing beam monitoring along the direction of the optimal estimated signal arrival angle;
decoding a beacon of a second target beam after monitoring the second target beam, wherein the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival;
if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful;
if the beacon of the second target beam cannot be successfully decoded, storing the second target beam in a beam set for storing an optimal beam;
if the beacon of the first target beam can be successfully decoded, the neighbor discovery is successful;
the obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information includes:
obtaining theoretical channel state information according to a preset channel model, wherein the preset channel model is as follows: a channel model constructed using beamforming of the antenna array;
establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
solving the target model to obtain an optimal estimated signal arrival angle;
the calculation method of the optimal estimated signal arrival angle comprises the following steps:
to generate the u-th beam, a series of beam weights are applied to the antenna elements, then NRThe beam generation gain of the linear antenna array with the elements in any space direction theta (n), namely a channel model A (u, u), is as follows:
where d is the spacing of the antenna elements, λ is the carrier wavelength, U ∈ [1, U]U is the total number of beams, w (U, i) is the weight vector corresponding to the U-th beam and the i-th antenna element, NRIs the number of elements of the linear antenna array, j is an imaginary number, exp (-) is e(·)I.e. e(·)Is an exponential function with a base number e, N is the number of spatial channels, N ∈ [1, …, N]N is the total number of the spatial channels, and N and N are positive integers;
obtaining theoretical channel state information according to the channel model
Wherein x (-) is a continuous spatial channel response function for all spatial angles;
establishing a target model of the channel state according to the theoretical channel state information, the channel state information and the channel space constraint condition; the specific process is as follows:
the channel of the u-th beam is measured and denoted as hms(u) obtaining a constraint equation according to the theoretical channel state information as follows:
the client obtains all P CSI measurements H along a series of beam Φ directionsmsIs recorded as Hms＝{hms(1),…,hms(P) }, the measurement results are:
AΦ,Nx＝Hms
AΦ,Ngenerating a matrix for the beam; hmsA matrix formed by the channel measurement results; p is the CSI measurement HmsX is a vector formed by x, and x is the continuous spatial channel response of all spatial angles;
the target model of the channel state is as follows:
min‖x‖1
s.t.AΦ,Nx＝Hms
wherein |1Is a first order norm, s.t. represents a constraint condition;
solving the target model of the channel state by using a convex optimization algorithm to obtain an optimal solution of the target model, wherein the optimal solution is the optimal estimated signal arrival angle
Performing beam monitoring along the direction of the optimal estimated signal arrival angle;
according to the best estimated signal arrival angle
I.e. the best solution, the best listening beam can be found
I.e. the beam that produces the strongest channel when combining antenna gain and channel gain:
wherein U is the number of beams,
the best estimated signal angle of arrival for the nth direction.
2. The method of claim 1, further comprising, after said storing the second target beam in the beam set for storing the best beam:
obtaining a distance between each beam in a second beam set and each beam in the first beam set, wherein the second beam set is as follows: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
determining a beam corresponding to the maximum distance in the second beam set in the obtained distances as a third target beam;
and decoding the beacon of the third target beam, and successfully discovering the neighbor.
3. The method of claim 2, wherein prior to said decoding the beacon of the third target beam, neighbor discovery being successful, further comprising:
judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value;
if so, executing the steps of decoding the beacon of the third target beam and successfully discovering the neighbor;
if not, continuing to monitor the beams supported by the antenna array, and returning to execute the step of decoding the beacon of the first target beam after monitoring the first target beam.
4. The method of any one of claims 1-3, wherein said extracting channel state information for a beacon of the first target beam comprises:
and extracting a preamble of the beacon of the first target beam, decoding the preamble, and obtaining channel state information of the beacon of the first target beam.
5. The method of claim 4, wherein the preamble is formed of a short training field consisting of X M-Golay sequences and a channel estimation field consisting of Y N-Golay sequences, wherein X, Y represents the number of the M-Golay sequences and the N-Golay sequences, respectively, and M, N represents the number of bits of the Golay sequences.
6. The method of claim 1, wherein solving the object model comprises:
and solving the target model by using a convex optimization algorithm.
7. A millimeter wave wireless network neighbor discovery device is characterized by comprising an accumulation spatial channel module, an optimal monitoring beam predicting module and a beam module with the largest distance, wherein the accumulation spatial channel module comprises:
a first decoding module, configured to decode a beacon of a first target beam after monitoring the first target beam, where the first target beam is: randomly selecting a beam supported by the antenna array; if the beacon of the first target beam can be successfully decoded, the neighbor finds that the beacon of the first target beam can not be successfully decoded, and a channel extraction module is triggered;
the channel extracting module is configured to extract channel state information of a beacon of the first target beam, and accumulate the channel state information of the beacon of the first target beam to spatial channel state information;
the optimal estimated signal arrival angle predicting module is used for obtaining an optimal estimated signal arrival angle according to a preset channel model and the spatial channel state information;
a beam monitoring module for predicting the optimal monitoring beam, which is used for performing beam monitoring along the direction of the optimal estimated signal arrival angle;
a second decoding module, configured to decode a beacon of a second target beam after monitoring the second target beam, where the second target beam is: randomly selecting a beam supported by an antenna array along the direction of the optimal estimated signal angle of arrival; if the beacon of the second target beam can be successfully decoded, the neighbor discovery is successful; triggering a beam set module if the beacon of the second target beam cannot be successfully decoded;
the beam set module is configured to store the second target beam in a beam set for storing an optimal beam;
wherein the module for predicting the best estimated signal arrival angle comprises:
the theoretical channel state information submodule is used for obtaining theoretical channel state information according to a preset channel model, wherein the preset channel model is as follows: a channel model constructed using beamforming of the antenna array;
the target model submodule is used for establishing a target model of the channel state of the beacon of the first target beam according to the theoretical channel state information, the channel state information and the channel space constraint condition of the beacon of the first target beam;
an optimal estimated signal arrival angle obtaining submodule, configured to solve the target model to obtain an optimal estimated signal arrival angle;
the calculation method of the optimal estimated signal arrival angle comprises the following steps:
to generate the u-th beam, a series of beam weights are applied to the antenna elements, then NRThe beam generation gain of the linear antenna array with the elements in any space direction theta (n), namely a channel model A (u, n), is as follows:
where d is the spacing of the antenna elements, λ is the carrier wavelength, U ∈ [1, U]U is the total number of beams, w (U, i) is the weight vector corresponding to the U-th beam and the i-th antenna element, NRIs the number of elements of the linear antenna array, j is an imaginary number, exp (-) is e(·)I.e. e(·)Is an exponential function with a base number e, N is the number of spatial channels, N ∈ [1, …, N]N is the total number of the spatial channels, and N and N are positive integers;
obtaining theoretical channel state information according to the channel model
Wherein x (-) is a continuous spatial channel response function for all spatial angles;
establishing a target model of the channel state according to the theoretical channel state information, the channel state information and the channel space constraint condition; the specific process is as follows:
the channel of the u-th beam is measured and denoted as hms(u) obtaining a constraint equation according to the theoretical channel state information as follows:
the client obtains all P CSI measurements H along a series of beam Φ directionsmsIs recorded as Hms＝{hms(1),…,hms(P) }, the measurement results are:
AΦ,Nx＝Hms
AΦ,Ngenerating a matrix for the beam; hmsA matrix formed by the channel measurement results; p is the CSI measurement HmsX is a vector formed by x, and x is the continuous spatial channel response of all spatial angles;
the target model of the channel state is as follows:
min‖x‖1
s.t.AΦ,Nx＝Hms
wherein |1Is a first order norm, s.t. represents a constraint condition;
solving the target model of the channel state by using a convex optimization algorithm to obtain an optimal solution of the target model, wherein the optimal solution is the optimal estimated signal arrival angle
Performing beam monitoring along the direction of the optimal estimated signal arrival angle;
according to the best estimated signal arrival angle
I.e. the best solution, the best listening beam can be found
I.e. the beam that produces the strongest channel when combining antenna gain and channel gain:
wherein U is the number of beams,
the best estimated signal angle of arrival for the nth direction.
8. The apparatus of claim 7, wherein the apparatus further comprises:
a distance calculating module, configured to obtain a distance between each beam in a second beam set and each beam in a first beam set, where the second beam set is: the method comprises the steps of collecting beams supported by an antenna array monitored in a preset time period;
a comparing module, configured to determine, as a third target beam, a beam corresponding to a maximum distance in the second beam set among the obtained distances;
and the third decoding module is used for decoding the beacon of the third target beam, and the neighbor discovery is successful.
9. The apparatus of claim 8, wherein the apparatus further comprises:
the judging module is used for judging whether the signal intensity of the third target beam is greater than or equal to a set signal intensity threshold value or not; if so, executing the steps of decoding the beacon of the third target beam and successfully discovering the neighbor; if not, triggering a monitoring beam module;
and the beam monitoring module is used for continuously monitoring the beams supported by the antenna array and returning to execute the step of decoding the beacon of the first target beam after the first target beam is monitored.
10. The apparatus of any one of claims 7-9, wherein the extract channel module comprises:
and the channel state information acquisition submodule is used for extracting the lead code of the beacon of the first target beam, decoding the lead code and acquiring the channel state information of the beacon of the first target beam.
11. An electronic device is characterized by comprising a processor, a communication interface, a memory and a communication bus, wherein the processor and the communication interface are used for realizing mutual communication by the memory through the communication bus;
a memory for storing a computer program;
a processor for implementing the method of any one of claims 1 to 6 when executing a program stored in a memory.
12. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the method of any one of claims 1 to 6.
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