CN1817053A - Antenna steering for an access point based upon probe signals - Google Patents
Antenna steering for an access point based upon probe signals Download PDFInfo
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- CN1817053A CN1817053A CNA2004800171796A CN200480017179A CN1817053A CN 1817053 A CN1817053 A CN 1817053A CN A2004800171796 A CNA2004800171796 A CN A2004800171796A CN 200480017179 A CN200480017179 A CN 200480017179A CN 1817053 A CN1817053 A CN 1817053A
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Abstract
A method for operating an access point in a wireless local area network (WLAN) is provided. The access point includes a directional antenna for communicating with a plurality of remote stations, and the directional antenna includes an omni angle and a plurality of directional angles. The method includes selecting one of the remote stations from the plurality of remote stations, transmitting a first probe signal via the omni angle of the directional antenna to the selected remote station, and measuring a first probe response signal received via the omni angle from the selected remote station responding to the first probe signal. A respective second probe signal is transmitted via each one of the plurality of directional angles of the directional antenna to the selected remote station, and a second probe response signal received via each directional angle from the selected remote station responding to the respective second probe signal is measured. The measured first probe response signal and the respective measured second probe response signals from the selected remote station are stored in an antenna database.
Description
Technical field
The present invention is the antenna steering algorithm about the access point that operates in WLAN about WLAN specifically.
Background technology
There are various standards to allow that distant station (such as portable computer) moves and be connected in a WLAN (WLAN) and are connected to one of cable network access point (AP) via radio frequency (RF) transmission.This cable network is commonly called wiring system (distribution system).Above-mentioned various standard comprises IEEE 802.11 standards and corresponding alphabetical revision version thereof, such as 802.11b and 802.11g.
Physical layer provides the low order transmission to use to allow these stations communicate by letter with access point one of in distant station and in access point.On this physical layer, there is medium access control (MAC) layer to provide such as authenticate, remove services such as authentication, the right of privacy, foundation association and disassociation.
In operation, when a distant station is reached the standard grade, at first can between the physical layer in this station and the access point, set up online.Just can connect the MAC layer then.Generally speaking, with regard to distant station and access point, physical layer RF signal utilizes unipole antenna to transmit and receive.
One unipole antenna is with all direction radiation, with regard to a vertical orientation assembly substantially with a horizontal plane radiation.Unipole antenna is easy to take place the communication quality deterioration between distant station and the access point, for example causes radio wave signal to reflect or diffraction because of object between two parties.Object comprises wall, desk and people for instance between two parties.These objects produce multipath, the decline of normality statistics, Rayleigh (Rayleigh) decline etc.Therefore, once had for the effort that the Signal Degrade that effect causes such as alleviates therefore.
A kind of technology that is used for offseting the deterioration of RF signal is to use two antennas that the diversity effect is provided.This two antenna is coupled to and is in the antenna diversity switch that distant station and access point one of them or the two have concurrently.Use two antennas in the hope of the basic theory of antenna diversity effect to be: no matter at any given time, at least one antenna receives that possibly one is not subjected to the signal of Multi-Path Effects in the middle of these antennas.Therefore, this antenna promptly is that distant station or access point are chosen the antenna that carries out transmitting/receiving signal via this antenna diversity switch.Need to solve the interior distant station of WLAN and the problem of the RF Signal Degrade between an access point but still have.
Summary of the invention
Because above-mentioned background, one of the present invention purpose is to improve communicating by letter between the access point and distant station in the WLAN.
A kind ofly surmount the improvement of simple diversity effect by a kind of antenna steering program that is used in the access point (that is radio network gateway) of WLAN.Directional antenna improves the circulation of network, and strengthens the scope between access point and distant station (that is wireless user's device).One directed antenna in most of the cases provides one to be higher than the signal to noise ratio of omnidirectional antenna, thereby allows that link operates with higher data transmission rate.
This antenna steering program can be in medium access control (MAC) layer that is present in access point, and is that the basis is chosen a best or preferable directional antenna and arranged with the signal quality metrics that can be provided by physical layer after the distant station received signal.
According to the present invention's principle, in the process of the exchanges data between for example login, authentication or subsequent access point and a selected distant station, judge and controlled one of access point antenna preferred direction.In one embodiment, make this judgement by software or firmware in the access point running.This access point antenna Control Software/firmware can be set up a database that comprises distant station identity and the antenna direction relevant with this station to reach the optimization usefulness of communicating by letter.
Can use the arrange in pairs or groups intrinsic diversity of traditional 802.11 equipment of hardware to select the circuit running to choose preferable directional antenna angle.Access point can utilize to post a letter and cause distant station to launch a probe response signal, and wherein this access point is measured the signal quality of this probe response signal.Whether this access point can be relatively should carry out a new antenna scanning operation to last tolerance corresponding to the signal of receiving from distant station with an omnidirectional antenna pattern to judge corresponding to the tolerance of the signal of receiving from distant station with a directed antenna mode.Hiding node occurs if access point is judged, it may utilize such as the defined request transmission/clears to send of 802.11 standards (RTS/CTS) cause a protection mechanism.
Adding with a directed antenna allly has double advantage in access point: promote multi-user's ability more in the circulation of indivedual distant stations and the network enabled.In most of RF environment, the signal bits that distant station is received will definitely be via allowing access point improve with the mode of the shaping antenna beam emission of the direction at this station of aiming.This shaping antenna beam can provide a 3-5dB gain benefit that is better than being deployed in traditionally the omnidirectional antenna of access point for instance.The signal level that strengthens allows that linking with higher data transmission rate between access point and the distant station operates, and particularly covering frequency band outside the ripple district.This directional antenna manipulative procedure is present in the access point with the operation of support with distant station.
More particular words it, the present invention is directed to the method for the interior access point of a kind of WLAN of operation, this access point comprises one and is used for being exchanged for directional antenna that basis communicate to comprise one of a plurality of control picture frames and data picture frame packet data with at least one distant station in a forward link.This directional antenna comprises a plurality of antenna patterns illustrated.This method comprise via one of this directional antenna first antenna patterns illustrated from this at least one distant station receive one first control picture frame, one first data picture frame is transmitted to this at least one distant station, and receives one second control picture frame from this at least one distant station via one of this directional antenna second antenna patterns illustrated.
This method more comprises the signal quality of the first control picture frame that measurement is received via this first antenna patterns illustrated and the signal quality of the second control picture frame received via this second antenna patterns illustrated, and relatively more relevant with this first and second antenna patterns illustrated corresponding signal quality that records.If relevant with this second antenna patterns illustrated signal quality that records surpasses relevant signal quality one predetermined threshold that records with this first antenna patterns illustrated, then choose this second antenna patterns illustrated this at least one distant station is launched one second data picture frame.
The operation of launching the first data picture frame can be and utilizes the preferable antenna patterns illustrated of one of this directional antenna to carry out, and wherein this more more comprises corresponding signal quality and the signal quality relevant with this preferable antenna patterns illustrated of recording that comparison is relevant with this first and second antenna patterns illustrated.If relevant with this second antenna patterns illustrated record signal quality surpass with this first with preferable antenna patterns illustrated relevant signal quality one predetermined threshold that records, then choose this second antenna patterns illustrated this at least one distant station launched one second data picture frame.
This first antenna patterns illustrated can comprise omnidirectional's angle, and this second antenna patterns illustrated can comprise a directed angle.Another selection, this first antenna patterns illustrated can comprise one first directional angle, and this second antenna patterns illustrated can comprise one second directional angle.This first control picture frame that is received can comprise a clear to send message, and this second control picture frame that is launched can comprise that one confirms message.
Another viewpoint of the present invention is at a kind of method of operating the access point in the WLAN, and this access point comprises one and is used for being exchanged for directional antenna that basis communicate to comprise one of a plurality of control picture frames and data picture frame packet data with at least one distant station in a backward chaining.This directional antenna comprises a plurality of antenna patterns illustrated.
This method comprises that more receiving one first via one of this directional antenna first antenna patterns illustrated from this at least one distant station controls picture frame, one second control picture frame is transmitted to this at least one distant station, and receives one first data picture frame from this at least one distant station via one of this directional antenna second antenna patterns illustrated.The signal quality of the signal quality of the first control picture frame that measurement is received via this first antenna patterns illustrated and the first data picture frame of receiving via this second antenna patterns illustrated.The relatively more relevant corresponding signal quality that records with this first and second antenna patterns illustrated.
This method more comprise when relevant with this second antenna patterns illustrated record signal quality surpass be correlated with this first antenna patterns illustrated record signal quality one predetermined threshold, then choose this second antenna patterns illustrated this at least one distant station launched one second data picture frame.
This first antenna patterns illustrated can comprise omnidirectional's angle, and this second antenna patterns illustrated can comprise a directed angle.Another selection, this first antenna patterns illustrated can comprise one first directional angle, and this second antenna patterns illustrated can comprise one second directional angle.This first control picture frame that is received can comprise that a request sends message, and this second control picture frame that is launched can comprise a clear to send message.
Another viewpoint of the present invention is at a kind of access point that is used for WLAN (WLAN), and it comprises that a directional antenna and that contains a plurality of antenna patterns illustrated is connected in the controller that this directional antenna is controlled.This controller can be configured as and be used for communicating by letter in a forward link with at least one distant station as previously mentioned.Another selection, this controller can be configured as and be used for communicating by letter in a backward chaining with at least one distant station as previously mentioned.
For further specifying above-mentioned purpose of the present invention, design feature and effect, the present invention is described in detail below with reference to accompanying drawing.
Description of drawings
Figure 1A is the sketch of the WLAN (WLAN) of utilization principle of the present invention;
Figure 1B is the sketch that is carrying out one of the antenna scanning access point in the WLAN of a Figure 1A;
Fig. 2 A one has the sketch of Figure 1A access point of exterior orientation antenna array;
Fig. 2 B is the sketch of Fig. 2 A access point, and wherein this directional antenna array is merged in the inner pcmcia card;
Fig. 3 A is the sketch of Fig. 2 A figure directional antenna array;
Fig. 3 B one is used for choosing the sketch of one of Fig. 3 A directional antenna antenna module state of switch;
Fig. 4 is the calcspar of a utilization according to the 1A figure access point of subsystem, layer and an antenna steering program of principle of the present invention;
Fig. 5 A one optionally is used for the signal sketch of Fig. 4 antenna steering program;
Fig. 5 B one optionally is used for the substitution signal sketch of Fig. 4 antenna steering program;
Fig. 6 is the alternative calcspar of a Fig. 4, wherein uses the antenna diversity circuit;
Fig. 7 one optionally is used for the signal sketch of the utilization concealed nodes technology of Fig. 4 antenna steering program;
Fig. 8 one possesses the vertical view of two-way Fig. 1 network of posting a letter;
Fig. 9 one possesses the vertical view of Fig. 1 network of antenna beam reading;
Figure 10 is one to be the flow chart of method of the access point of fundamental operation WLAN with the space diversity according to the present invention;
Figure 11 is one to be the flow chart of method of the access point of fundamental operation WLAN with the detectable signal according to the present invention;
Figure 12 and Figure 13 are respectively to be the flow chart of method of the access point of fundamental operation WLAN with the control picture frame in forward direction and the backward chaining according to the present invention; And
Figure 14 one is recognized as the flow chart of method of the access point of fundamental operation WLAN according to the present invention with concealed nodes.
Embodiment
Appended graphic the present invention of illustrating in greater detail of preferred embodiment of the present invention is drawn in following reference.Right the present invention can also many multi-form enforcement and should be illustrated as and only limit to the described embodiment of this specification; These embodiment just are used for allowing this specification more thoroughly complete, and can contain scope of the present invention fully to haveing the knack of this skill person.Full content indicates same components with same numbers, and uses the stress mark to indicate similar assembly in alternate embodiment.
Explanation has the WLAN (WLAN) 100 of a wiring system 105 with reference to Figure 1A at the beginning.Access point 110a, 110b and 110c are connected to wiring system 105 via wired connection such as cable data network connected mode.Each access point 110a, 110b and 110c have respective regions 115a, 115b, the 115c that can communicate by letter with distant station 120a, 120b, 120c via radio frequency (RF) signal.Distant station 120a, 120b, 120c are equipped with the WLAN hardware and software with access wiring system 105.In the following description, when desire is made a general name address to access point, distant station and zone, can use reference number 110,120 and 115 respectively.
Current techniques provides antenna diversity for access point 110 and distant station 120.Antenna diversity allows that access point 110 and distant station 120 are that the basis is chosen two antennas and wherein one provided the work of transmitting and receiving with the signal quality of receiving.A reason of bypassing other antenna and choosing an antenna occurs in the situation of multipath decline, wherein one adopts the signal in two different paths to cause the signal cancellation effect at an antenna, but can not at another antenna.Another example is to cause in the interference because of two unlike signals that the same antenna is received.Choose two antennas wherein another reason system of one for example shown in arrow 125, taken to from the 3rd district 115c in the first or second district 115a, the 115b as a distant station 120c because environment change.
Figure 1B is the calcspar of one of network shown in Figure 1A 100 subclass, wherein draws the directional antenna lobe 130a-130i of the access point 110b of utilization principle of the present invention in more detail.Directional antenna lobe 130a-130i also can totally be denoted as reference number 130.Access point 110b in an environmental scanning process in regular turn by antenna lobe 130 to judge a preferable antenna direction.
In the one scan process, access point 110b uses just like Fig. 2 A and the more detailed directional antenna scanning search distant station 120b RF signals transmitted of drawing of Fig. 2 B.In each scanning direction (that is angle or antenna patterns illustrated), access point 110b measures a signal or probe response and calculates the corresponding tolerance of one of this scanning angle.The example of tolerance comprises received signal intensity reading (RSSI), carrier wave-interference ratio (C/I), and energy-position is than (Eb/No), or other suitable tolerance of the quality of received signal or signal environment, such as signal to noise ratio (snr).The combination of one of these measuring values also can be used to judge best or preferable antenna alignment, can understand easily as those of ordinary skills.Record signal quality metrics according to these, access point 110b judges the preferable aerial angle or the direction of communicating by letter with distant station 120b.
These scannings can be certified and taken place with before or after wiring system 105 combines at distant station 110b.Therefore, initial antenna scanning may be to finish in the MAC layer.Another selection, initial antenna scanning can be beyond the MAC layer and finish.Similarly, authenticated and can be with the scanning that takes place after wiring system 105 combines and in the MAC layer, finish or finish at distant station 110b by the program that occurs in beyond the MAC layer.
Fig. 2 A is the sketch of the access point 110 of a use one exterior orientation antenna array 200a.Directional antenna array 200a comprises five one pole passive antenna element 205a, 205b, 205c, 205d and 205e and an one pole active antenna 206. Passive antenna element 205a, 205b, 205c, 205d and 205e totally indicate with reference number 205 hereinafter.Directional antenna array 200a is connected to access point 110 via a universal serial bus (USB) port 215.Directional antenna array 200a also accepts being connected of other type with 110 of access points.
Passive antenna element 205 in the directional antenna array 200a is coupled to active antenna 206 autoeciously to allow scanning.In this manual, at least one antenna beam that " scanning " means directional antenna array 200a can rotate with the increment relevant with the quantity of passive antenna element 205, and it optionally can revolve three-sixth turn.
One of directional antenna array 200a describes in detail and to be provided on January 24th, 2002 invention disclosed name and to be called in No. the 2002/0008672nd, the U.S. Patent Publication case of " adaptive antennas that is used for wireless communication system ", and this case is incorporated herein by reference and its existing assignee to the present invention of having been amortized.Received or the signal launched is that the sample method of basic optimization antenna direction also is disclosed in this case with directional antenna array 200a.
Fig. 2 B figure one possesses the isometric views of the access point 110 of an inner orientation antenna 220b.In this embodiment, directional antenna array 200b is positioned on the pcmcia card 220.Pcmcia card 220 is to carry and be connected in a processor (not shown) by access point 110.Directional antenna array 200b provides the identical functions with the 200a of directional antenna array shown in the 2A figure.
It will be appreciated that still has the directional antenna of numerous other forms array to use.Example comprise be disclosed in the denomination of invention of awarding card on January 4th, 2003 for No. the 6515635th, the United States Patent (USP) of " adaptive antennas that is used for wireless communication system " and March in 2002 bulletin on the 28th denomination of invention be No. the 2002/0036586th, the United States Patent (USP) bulletin case of " adaptive antennas that is used for wireless communication system ", the two is incorporated herein by reference and its assignee that has now to the present invention of having been amortized.
Fig. 3 A is just like the preceding described details drawing that comprises the directional antenna array 200a of passive antenna element 205 and active antenna 206.Directional antenna array 200a also comprise one with the ground plane 330 of passive antenna element electric coupling, it is described to see below Fig. 3 B.
Still with reference to Fig. 3 A, directional antenna array 200a provides one from antenna module 205a and the oblique directional antenna lobe of leaving 300 of 205e.This is in the sign that a reflective-mode and antenna module 205b, 205c and 205d are in a transmission mode for antenna module 205a and 205e.In other words, coupling mutually between active antenna 206 and the passive antenna element 205 allowed directional antenna array 200a scan orientation antenna lobe 300, and in present case, this lobe is led as shown in the figure because of the pattern of both establishing of passive component 205.As have the knack of this skill person and can understand, the different mode combination of passive antenna element 205 can cause different antenna lobes 300 field patterns and angle.
Fig. 3 B one can be used to passive antenna element 205 is set at the sketch of the example circuit of reflective-mode or transmission mode.Reflective-mode is indicated by a representative long dotted line 305, and transmission mode is indicated by a short dash line 310. Representative mode 305 and 310 is respectively to cause via the mode that an Inductive component 320 or a capacitance component 325 are coupled to a ground plane 330.Passive antenna element 205a is undertaken by coupling via a switch 315 of Inductive component 320 or capacitance component 325.Switch 315 can be the mechanical switch or the electric switch that passive antenna element 205a can be coupled to ground plane 330.Switch 315 is to set via a control signal 335.
That be coupled to ground plane 330 via inductor 320 is passive antenna element 205a, and it is prolonged shown in long representative dotted line 305 effectively.This can be considered is to provide one " backboard (backboard) " for a RF signal that is coupled in passive antenna element 205a via coupling mutually of passive antenna element 205a and active antenna 206.In 3A field pattern example, the two is connected in ground plane 330 via corresponding Inductive component 320 passive antenna element 205a and 205e.At the same time, in Fig. 3 A example, other passive antenna element 205b, 205c and 205d are electrically connected on ground plane 330 via corresponding capacitance assembly 325.
The capacitive coupling effect is shortened passive antenna element effectively shown in short representative dotted line 310.All the capacitive coupling effect of passive component 325 makes directional antenna array 200a become an omnidirectional antenna effectively.It will be appreciated that also the technology of coupling that substitutes to be used between passive antenna element 205 and the ground plane 330, for example delay line and lumped impedance.
Jump to Fig. 9, it provides by utilization directional antenna array 200a or 200b and makes access point 110b produce the vertical view of an omni-directional antenna pattern 905 and a directed antenna patterns illustrated 910.Access point 110b communicates by letter with a plurality of station 120a-120d.Because access point 110 is installed as and is not had barrier or mobile reflector in its vicinity (for example being mounted on the wall on eminence or the ceiling) usually by long distance, the selection of preferable antenna patterns illustrated direction probably not can with the online whole process of a given distant station 120 in change.
Icon access point 110b may use a directed antenna 200a that downlink data picture frame is transmitted to a selected distant station 120c.With regard to great majority broadcasting and control picture frame, access point can use omni-directional antenna pattern 905 and minimum available data transmission rate all can receive to guarantee all distant stations 120.Directional antenna 200a can't add the area of containing of macroreticular 100, but may improve the message transmission rate of the data picture frame that sends to distant station 120.The downlink transmissions speed that strengthens has its benefit, because the most data that shift on network 100 obviously are downlink (for example webpage access, archives shift).It is to be required utilization switch type space diversity in the omni-directional mode reception at access point 110b that one option is arranged.For instance, the link enough and to spare that may increase of 5dB provides 300% circulation recruitment.
Any distant station in contention (CP), sends on the access point 110b row link data picture frame by selected distant station 120c and utilizes omni-directional antenna pattern to receive, because all may be launched this picture frame.With regard to big picture frame, network configuration may require distant station to adopt request transmission/clear to send (RTS/CTS) mechanism to subscribe wireless medium.In this case, access point 110b can a directed pattern receive to strengthen the message transmission rate of uplink.How much this is the message transmission rate selection algorithm that depends in distant station 120c utilization.
In downlink transmissions, access point 110b may determine to use in contention an omnidirectional's field pattern and a lower data transmission rate to launch little package.It is former because distant station (such as distant station 120e) can't hear that the access point that sends from the directional antenna field pattern back to its sensings transmits content one of on the side of region of convergence " another ".This is many " concealed nodes " problems of being familiar with, and wherein two distant stations 120 are not heard the other side mutually and finished emission at one time.In this case, this two distant station is 120c and 120e.A kind of avoid this problem, particularly to big data picture frame effective method hereinafter with reference to Fig. 7 explanation.
Be can be for providing the higher data transmission rate with downlink and uplink data picture frame as distant station 120 exchanges of network traffic main body with the directional antenna field pattern at access point 110 places.Network on-line is maintained at the nominal gain of the omnidirectional antenna of access point 110.That is to say that distant station 120 can combine and keep online with access point 110 and need not use directional antenna 200a.
Must be defined as utilizing the omnidirectional of directional antenna 200a and the advantage of directional characteristic as the regular collection that table 1 provided.Table 1 comprises the address and the selection of existing antenna direction thereof of the relevant distant station 120 of current and access point 110.Table 1 can be that basic description example antenna direction is selected according to the picture frame sequence of 802.11 standards (table 21 and 22 within it).In table 1, " Dir " finger direction, " UL " refers to uplink, and " DL " refers to downlink.
Table 1-example antenna selective rule
| Sequence | Dir | It line options | |
| Beacon | DL | Omnidirectional | |
| Data | DL | Directed | Referring to Fig. 5 A |
| The RTS-CTS data | UL | Omnidirectional/orientation | Referring to Fig. 5 B |
One program can be judged the regular collection explanation of when choosing omnidirectional's field pattern and when choosing a directed field pattern by one.For instance, access point 110 can be chosen a directed field pattern in the time interval to 120 emissions of single distant station or reception the time.
One calcspar that the interface of access point 110 is shown is plotted in Fig. 4.Icon access point 110 comprises a plurality of subsystems and layer.One antenna subsystem 405 can comprise directional antenna 220b and be used for operating support circuit, bus and the software of this directional antenna.Antenna subsystem 405 has a common boundary with physical layer 410 and provides RF signal 412 to the latter.
Hereinafter illustrate according to the present invention and be used for judging the various technology of a directed antenna 220b being pointed to the preferred direction of a distant station 120 from an access point 110.First kind of technology used a space diversity choice mechanism.Second kind of technology utilization is in the detectable signal sequence of access point 110 and 120 exchanges of distant station.The third technology utilization control message (for example ACK or CTS) is made the signal quality measuring value of reception antenna direction at access point 110.The third technology can be applicable to forward direction and backward chaining the two.
First kind of technology supposes that existing 802.11 devices are included the diversity scanning/control of antenna switch type in and following 802.11 devices such as the 802.11a/802.11g/802.11n also can support the switch type diversity.This first technology is authenticated and with available after a network combines at a distant station 120.It is supposed that initial antenna scanning ties up in the MAC/ network layer protocol and finishes.Use an orientation or multi-component antenna 220a, this first technology can utilize diversity protocol to make aerial position/selection keep upgrading.
Modern with reference to Fig. 6, the effect of this first technology is as follows.Icon access point 110 ' comprises a controller 600 ' that is connected in antenna subsystem 405 '.Controller 600 ' comprises that one is endowed a physical layer 410 ' and the MAC layer (Fig. 4) to the access of antenna control signal.This MAC layer writes the sky line options in buffer A 605a ' and the buffer B 605b '.Buffer A 605a ' holds selected aerial position, and buffer B 605b ' holds an alternate antenna position.Physical layer 410 ' is also communicated by letter with a multiplexer 610 '.Physical layer 410 ' selects control mode that multiplexer 610 ' is sent a diversity selector switch control signal 607 ' with a traditional diversity, but uses the diversity selector switch control signal of holding within control buffer A 605a ' or the buffer B 605b ' in this case.
Should selected aerial position during network authentication/, select at the very start in conjunction with agreement.This alternate antenna position is any other aerial position (comprising an omni-directional mode).This alternate antenna position changes with a predefined procedure after receiving an effective package or after not receiving any package through one period scheduled time.
After successfully receiving a package, physical layer 410 ' sends at the received signal quality of this two aerial position the MAC layer and measures (signal strength signal intensity, signal to noise ratio, multipath/equalizer tolerance etc.).In the package receiving course, physical layer 410 ' is as operating as being used for 802.11 now; That is to say that switching and use receive best aerial position to package between this two aerial position.After physical layer 410 ' is received effective package, the signal quality metrics of this two aerial position is sent to the MAC layer.The MAC layer upgrades selected aerial position and alternate antenna position.It is best position, basis that this selected aerial position is replaced by with the data of receiving from physical layer 410 '.Can utilize filtering/hysteresis to avoid " ping-pong phenomenon (ping-ponging) " between two aerial positions.
As previously mentioned, the advantage of the existing 802.11 antenna switch type deversity schemes of this technology utilization.It will be appreciated that this first technology can comprise hardware, software/firmware or above combination.
Modern with reference to Figure 10, it will illustrate with the space diversity flow chart of the preceding method that is one of the interior access point 110 of fundamental operation one WLAN 100.From starting point (square 1000), this method comprises utilizes the existing angle of one of directional antenna 220b to communicate by letter with distant station 120, as square 1010.What carry out at square 1020 is that inswept directional antenna 220b is used for more than distant station 120 is communicated by letter for using angle during lead code.What carry out at square 1030 is to measure via existing angle and a plurality of for the corresponding signal of receiving from distant station 120 with angle.At square 1040, during this lead code with record signal be the basis choose this existing angle or a plurality of for angle wherein an angle be one to continue the preferred angle communicate by letter with distant station 120.This method finishes at square 105.
Second kind of technology is with the emission of the RTS message of 110 pairs of distant stations 120 of access point and the distant station basis that is received as to the CTS message of access point response emission.802.11 standard also defines one and surveys requirements/probe response and exchange, this is used for judging link quality to other stations 120 by distant station 120 usually.
Be used for by access point 110 judging that preferable pointing direction to a selected distant station 120 is when (as shown in Figure 8), access point 110 may directed field pattern 130 emissions one detection require signal with omnidirectional's field pattern and each, and measures from the signal quality of the probe response signal 810 of distant station 110 loopbacks in corresponding field pattern running.
The measurement of these response picture frames 810 becomes than aforementioned diversity selection technology it more the technology of leaning on.This second technology preferably is to use immediately with after access point 110 combines at a distant station 120 at least.Though use extra detection require/the probe response signal can impact network efficiency, these exchanges may seldom take place.
Modern with reference to Figure 11, it will illustrate with the detectable signal flow chart of the preceding method that is one of the interior access point 110 of fundamental operation one WLAN 100.From starting point (square 1100), this method is included in square 1110 and chooses a distant station 120, via omnidirectional's angle of directional antenna 220b this selected distant station is launched one first detectable signal at square 1120, and measure via this omnidirectional's angle at square 1130 and one of to receive the first probe response signal in response to this first detectable signal from this selected distant station.
At square 1140, each angle more than directional antenna 200b in the middle of the directional angle is to selected distant station 120 emissions one corresponding second detectable signal, and measures via each directional angle at square 1150 and one of to receive the second probe response signal in response to this corresponding second detectable signal from this selected distant station.At square 1160, in the future free decide distant station 120 record the first probe response signal and the corresponding second probe response signal that records is stored in the antenna database.
At square 1170, recording the second probe response signal with these serves as that a preferable directional angle is chosen at selected distant station 120 in the basis.At square 1180, relatively derive from recording the first probe response signal and deriving from the second probe response signal that records of this preferable directional angle of this omnidirectional's angle.This first detectable signal comprises that a request sends (RTS) message and this first probe response signal comprises a clear to send (CTS) message.Similarly, this second detectable signal comprises that a RTS message and this second probe response signal comprise a CTS message.At square 1190, relatively be that the basis is chosen the preferable directional angle of this omnidirectional's angle or this and continued and select distant station 120 and communicate by letter with this.This method finishes at square 1195.
The utilization of the third technology is used in the control picture frame of the normality exchanges data of 120 of access point 110 and distant stations.This technology can be used in forward link communication and backward chaining and communicates by letter in the two.Because clear to send (CTS) and confirm that (ACK) message system sends with lower data transmission rate, access point 110 can be with these message comparison omnidirectional field patterns 905 and the directed field pattern of selecting for use now 130.This is plotted in Fig. 5 A, in sky line options timing dotted line is arranged among the figure.It can be used as and is used for judging and selects for use direction 130 whether can possess the method that it surmounts the advantage of omnidirectional's field pattern 905 now.This advantage is switched normally based on a predetermined threshold in order to avoid having between two antenna patterns illustrated of similarity signal quality metric frequently.
For instance, during the CTS message, available omni-directional mode receives this message to calculate one first signal quality measuring value.During the ACK message, an available test antenna direction receives this message to calculate a secondary signal quality measuring value.Carry out the comparison of this first and second signal qualitys measuring value and judge whether this test antenna direction should be stored.That is to say whether directional pattern provides a gain that is higher than omni-directional mode.Also can carry out two comparisons between the different directional antenna directions.
The direction table 425 of Fig. 4 can add from the omnidirectional of aforementioned program and the signal quality measuring value of preferential direction antenna patterns illustrated.If advantage is low below a predetermined threshold, then access point 110 is replied to omnidirectional's selection and is utilized above-mentioned preceding two kinds of technology one of them carries out the antenna search.
Just in case the lay-up period that distant station 120 enters an energy saver mode or do not have data to shift for a long time, access point 110 are replied the field pattern selection for omnidirectional.When distant station 120 becomes once more active, access point 110 can carry out the search of another antenna.
Modern with reference to Figure 12 and Figure 13, illustrate with the control picture frame in forward direction and the backward chaining to be the flow chart of the method for one of the interior access point 120 of fundamental operation one WLAN 100 respectively.From starting point (square 1200), this method is included in square 1210 and receives one first control picture frame via one of directional antenna 220b first antenna patterns illustrated from distant station 120 in a forward link, and at square 1,220 one first data picture frame is transmitted to this distant station, and receives one second control picture frame via one of this directional antenna second antenna patterns illustrated from this distant station at square 1230.Measure the signal quality of the second control picture frame that the signal quality and of first a control picture frame of receiving via this first antenna patterns illustrated receives via this second antenna patterns illustrated at square 1240.Compare corresponding the record signal quality relevant at square 1250 with this first and second antenna patterns illustrated.If relevant with this second antenna patterns illustrated signal quality that records surpasses relevant signal quality one predetermined threshold that records with this first antenna patterns illustrated, then choose this second antenna patterns illustrated in order to distant station 120 is launched one second data picture frame at square 1260.The first control picture frame of receiving comprises a clear to send message, and the second control picture frame of receiving comprises that one confirms message.This method finishes at square 1270.
Being used for the control picture frame in the backward chaining is that the method for access point 120 comprises from starting point (square 1300) one of in fundamental operation one WLAN 100, receive one first control picture frame via one of directional antenna 220b first antenna patterns illustrated from distant station at square 1310, at square 1,320 one second control picture frame is transmitted to this distant station, and receives one first data picture frame via one of this directional antenna second antenna patterns illustrated from this distant station at square 1330.Measure the signal quality of the first data picture frame that the signal quality and of first a control picture frame of receiving via this first antenna patterns illustrated receives via this second antenna patterns illustrated at square 1340.Compare corresponding the record signal quality relevant at square 1350 with this first and second antenna patterns illustrated.If relevant with this second antenna patterns illustrated signal quality that records surpasses relevant signal quality one predetermined threshold that records with this first antenna patterns illustrated, then choose this second antenna patterns illustrated and allow 110 pairs of distant stations of access point 120 launch one second data picture frame at square 1360.The first control picture frame of receiving comprises that a request sends message, and the second control picture frame of emission comprises a clear to send message.This method finishes at square 1370.
The 4th kind of technology is a concealed nodes resist technology, and it provides a protection mechanism to reduce or the incidence of the concealed nodes of preventing when access point 110 uses a directed antenna 220b.Concealed nodes occur in be not in the network 100 all distant stations 120 can both hear in the communicating by letter of access point 110 and 120 of selected distant stations that therefore the distant station of not heard may be launched in being used at medium.This can cause collision, particularly at access point 110.
When access point 110 has the data that will be transmitted to a distant station 120, whether control program is set selected antenna direction in the mode of the direction table 425 of scintigram 4 has potential concealed nodes to judge.For instance, access point 110 can be just in contrast to the direction finding distant station 120 of selecting antenna direction.
With reference to the chronogram of Fig. 7, if judging, Control Software might have concealed nodes, access point 110 at first utilizes the omni-directional mode of antenna 220a that one known untapped MAC Address is launched a CTS message.This program system is used for informing in the network that all distant stations 120 have an exchanging operation to take place and can not launch before exchange is finished.Access point 110 switches to the selected antenna direction of expection distant station 120 and communicates then.The another program that prevents hidden node problem is to hope that with first phase distant station 120 carries out four-way picture frame exchange agreement (RTS, CTS, data and ACK).
If Control Software judges that concealed nodes can not be arranged, access point 110 can not send the CTS message and can become in access point 110 antenna settings and begin communication immediately in the correct direction.If procotol has requirement, the RTS message must be fed to the receiver of expection, causes a CTS message to get back to access point 110 and is used as the affirmation message, shown in Fig. 5 A.
It is also noted that in the described program of reference Fig. 7 usefulness is not to be promoted by access point 110 emissions because of the RTS message, just only needs the CTS message because will make distant station 120 stop emission.The distant station of pointing out in the ID section of standard 802.11 agreement headers 120 guarantees that this assigning remote station receives the data picture frame.
Modern with reference to Figure 14, the method that is recognized as one of the interior access point 120 of fundamental operation one WLAN 100 with concealed nodes be described.From starting point (square 1400), this method is included in 1410 by being that related mode is created an antenna database with the corresponding signal quality that records corresponding to a plurality of antenna patterns illustrated between access point 110 and each distant station 120.These corresponding signal qualitys that record serve as that the basis is judged by access point 110 with itself and communicating by letter of each distant station 120.Serves as that the basis is judged and to be used for the preferable antenna patterns illustrated of one of each distant station 120 at square 1420 with this antenna database, and chooses a distant station and corresponding preferable antenna patterns illustrated to communicate at square 1430.At square 1440, based on this antenna database and with judge whether have any distant station that is not selected also not know in taking place in that these communications are actual before selected distant station is communicated by letter.This be by relatively more relevant with the preferable antenna patterns illustrated of this selected distant station record signal quality and when not being selected distant station and using identical preferable antenna patterns illustrated the mode of relevant corresponding signal quality judge.
If have a concealed nodes, then give expression to the message that access point 110 and selected distant station 120 are about to mutual communication in square 1450 broadcasting one.As previously mentioned, this broadcasting can be and is one and sends to the form of the active clear to send message of distant station 120 via omni-directional antenna pattern.This CTS has a not use address that does not correspond to any distant station 120.Another selection is carried out four-way picture frame exchange agreement (RTS, CTS, data and ACK) in case hidden node problem with selected distant station 120.This method finishes at square 1460.
Though below with reference to the present invention's preferred embodiment specifically scheming and explanatory note the present invention, have the knack of this skill person and will appreciate that can not break away from the invention scope that the claim item contained makes various variation with regard to form and details.For instance, access point is not limited to IEEE 802.11 standards.Access point antenna algorithm as previously mentioned as have the knack of this skill person can understand the LAN that can be applicable to other type easily, such as the defined LAN of IEEE 802.16 standards.
Claims (36)
1. the method for the access point in the operate wireless LAN (WLAN), this access point comprises a directed antenna, be used in a forward link, being exchanged for the basis and communicating to comprise one of a plurality of control picture frames and data picture frame packet data with at least one distant station, this directional antenna comprises a plurality of antenna patterns illustrated, and this method comprises:
Via one first antenna patterns illustrated of this directional antenna, receive one first control picture frame from this at least one distant station;
Launch one first data picture frame to this at least one distant station;
Via one second antenna patterns illustrated of this directional antenna, receive one second control picture frame from this at least one distant station;
One signal quality of one signal quality of this first control picture frame that measurement is received via this first antenna patterns illustrated and this second control picture frame of being received via this second antenna patterns illustrated; And
Relatively more relevant corresponding measures signal quality with this first and second antenna patterns illustrated.
2. the method for claim 1, it is characterized in that: also comprise when relevant with this second antenna patterns illustrated measures signal quality surpasses measures signal quality one predetermined threshold relevant with this first antenna patterns illustrated, then choose this second antenna patterns illustrated to launch one second data picture frame to this at least one distant station.
3. the method for claim 1, it is characterized in that: the step of launching the first data picture frame is to utilize a preferable antenna patterns illustrated of this directional antenna to carry out; And wherein this comparison step more comprise corresponding measures signal quality that comparison is relevant with this first and second antenna patterns illustrated and with this preferable antenna patterns illustrated one of relevant signal quality.
4. method as claimed in claim 3, it is characterized in that: also comprise when the measures signal quality relevant with this second antenna patterns illustrated surpasses with this first measures signal quality one predetermined threshold relevant with preferable antenna patterns illustrated, then choose this second antenna patterns illustrated, in order to launch one second data picture frame to this at least one distant station.
5. the method for claim 1, it is characterized in that: this first antenna patterns illustrated comprises omnidirectional's angle, and this second antenna patterns illustrated comprises a directed angle.
6. the method for claim 1, wherein this first antenna patterns illustrated comprises one first directional angle, and this second antenna patterns illustrated comprises one second directional angle.
7. the method for claim 1 is characterized in that: this first control picture frame that is received comprises a clear to send message, and this second control picture frame that is received comprises that one confirms message.
8. the method for claim 1 is characterized in that: comprise that also generation one comprises the antenna database of the corresponding measures signal quality relevant with this first and second antenna patterns illustrated.
9. the method for claim 1 is characterized in that: also comprise and choose this first antenna patterns illustrated and this second antenna patterns illustrated, and wherein this is chosen step and ties up to this access point and get medium access control (MAC) layer and carry out.
10. the method for claim 1 is characterized in that: the step of measuring the corresponding signal quality comprise judge that a received signal intensity reading, one carrier wave-interference ratio, an energy-position are compared and a signal to noise ratio at least one of them.
11. the method for claim 1 is characterized in that: this access point is based on an IEEE 802.11 standards and one of them the standard running of an IEEE 802.16 standards.
12. the method for claim 1, wherein this directional antenna comprises at least one driving component and a plurality of passive component.
13. the method for the access point in the operate wireless LAN (WLAN), this access point comprises a directed antenna, be used in a backward chaining, being exchanged for the basis and communicating to comprise one of a plurality of control picture frames and data picture frame packet data with at least one distant station, this directional antenna comprises a plurality of antenna patterns illustrated, and this method comprises:
Via one first antenna patterns illustrated of this directional antenna, receive one first control picture frame from this at least one distant station;
Launch one second control picture frame to this at least one distant station;
One second antenna patterns illustrated via this directional antenna receives one first data picture frame from this at least one distant station;
One signal quality of one signal quality of this first control picture frame that measurement is received via this first antenna patterns illustrated and this first data picture frame of being received via this second antenna patterns illustrated;
Relatively more relevant corresponding measures signal quality with this first and second antenna patterns illustrated.
14. method as claimed in claim 13, it is characterized in that: also comprise when the measures signal quality relevant with this second antenna patterns illustrated surpasses measures signal quality one predetermined threshold relevant with this first antenna patterns illustrated, then choose this second antenna patterns illustrated, in order to launch one second data picture frame via this access point to this at least one distant station.
15. method as claimed in claim 13 is characterized in that: this first antenna patterns illustrated comprises omnidirectional's angle, and this second antenna patterns illustrated comprises a directed angle.
16. method as claimed in claim 13 is characterized in that: this first antenna patterns illustrated comprises one first directional angle, and this second antenna patterns illustrated comprises one second directional angle.
17. method as claimed in claim 13 is characterized in that: this first control picture frame that is received comprises that a request sends message, and this second control picture frame of being launched comprises a clear to send message.
18. method as claimed in claim 13 is characterized in that: comprise that also generation one comprises the antenna database of the corresponding measures signal quality relevant with this first and second antenna patterns illustrated.
19. method as claimed in claim 13 is characterized in that: this directional antenna comprises at least one driving component and a plurality of passive component.
20. an access point that is used for WLAN (WLAN), it comprises:
One contains the directional antenna of a plurality of antenna patterns illustrated; And
One is connected in the controller that this directional antenna is controlled, and this controller and at least one distant station are exchanged for the basis with a packet data that comprises a plurality of control picture frames and a data picture frame and communicate this controller in a forward link
Via one first antenna patterns illustrated of this directional antenna, receive one first control picture frame from this at least one distant station;
Launch one first data picture frame to this at least one distant station;
Via one second antenna patterns illustrated of this directional antenna, receive one second control picture frame from this at least one distant station;
One signal quality of one signal quality of this first control picture frame that measurement is received via this first antenna patterns illustrated and this second control picture frame of being received via this second antenna patterns illustrated; And
Relatively more relevant corresponding measures signal quality with this first and second antenna patterns illustrated.
21. access point as claimed in claim 20 is characterized in that: this directional antenna comprises at least one driving component and a plurality of passive component.
22. access point as claimed in claim 20, it is characterized in that: when this controller surpasses measures signal quality one predetermined threshold relevant with this first antenna patterns illustrated in the measures signal quality relevant with this second antenna patterns illustrated, choose this second antenna patterns illustrated, in order to launch next number according to picture frame to this at least one distant station.
23. access point as claimed in claim 20 is characterized in that: the step of launching this data picture frame is to utilize a preferable antenna patterns illustrated of this directional antenna to carry out by this controller; And wherein the comparison step of being undertaken by this controller more comprises comparison corresponding measures signal quality relevant with this first and second antenna patterns illustrated and a signal quality relevant with this preferable antenna patterns illustrated.
24. access point as claimed in claim 23, it is characterized in that: this controller the measures signal quality relevant with this second antenna patterns illustrated surpass with this first and this preferable antenna patterns illustrated be correlated with measures signal quality one predetermined threshold the time, choose this second antenna patterns illustrated, in order to launch one second data picture frame to this at least one distant station.
25. access point as claimed in claim 20 is characterized in that: this first antenna patterns illustrated comprises omnidirectional's angle, and this second antenna patterns illustrated comprises a directed angle.
26. access point as claimed in claim 20 is characterized in that: this first antenna patterns illustrated comprises one first directional angle, and this second antenna patterns illustrated comprises one second directional angle.
27. access point as claimed in claim 20 is characterized in that: this first control picture frame that is received comprises a clear to send message, and this second control picture frame of being launched comprises that one confirms message.
28. access point as claimed in claim 20 is characterized in that: this controller produces one and comprises the antenna database of the corresponding measures signal quality relevant with this first and second antenna patterns illustrated, and stores this antenna database.
29. access point as claimed in claim 20 is characterized in that: this controller comprises a physical layer and medium access control (MAC) layer, and the step of choosing of this first antenna patterns illustrated and this second antenna patterns illustrated is to carry out at this MAC layer.
30. access point as claimed in claim 20 is characterized in that: this controller is to judge that one of them is a basic measurement corresponding signal quality at least for a received signal intensity reading, one carrier wave-interference ratio, an energy-position ratio and a signal to noise ratio.
31. an access point that is used for WLAN (WLAN), it comprises:
One contains the directional antenna of a plurality of antenna patterns illustrated; And
One is connected in the controller that this directional antenna is controlled, and this controller and at least one distant station are exchanged for the basis and communicate this controller to comprise one of a plurality of control picture frames and data picture frame packet data in a backward chaining
Via one first antenna patterns illustrated of this directional antenna, receive one first control picture frame from this at least one distant station;
Launch one second control picture frame to this at least one distant station;
One second antenna patterns illustrated via this directional antenna receives one first data picture frame from this at least one distant station;
One signal quality of one signal quality of this first control picture frame that measurement is received via this first antenna patterns illustrated and this first data picture frame of being received via this second antenna patterns illustrated; And
Relatively more relevant corresponding measures signal quality with this first and second antenna patterns illustrated.
32. access point as claimed in claim 31 is characterized in that: this directional antenna comprises at least one driving component and a plurality of passive component.
33. access point as claimed in claim 31, it is characterized in that: when this controller surpasses measures signal quality one predetermined threshold relevant with this first antenna patterns illustrated in the measures signal quality relevant with this second antenna patterns illustrated, choose this second antenna patterns illustrated, in order to launch one second data picture frame to this at least one distant station.
34. access point as claimed in claim 31 is characterized in that: this first antenna patterns illustrated comprises omnidirectional's angle, and this second antenna patterns illustrated comprises a directed angle.
35. access point as claimed in claim 31 is characterized in that: this first antenna patterns illustrated comprises one first directional angle, and this second antenna patterns illustrated comprises one second directional angle.
36. access point as claimed in claim 31 is characterized in that: this first control picture frame that is received comprises that a request sends message, and this second control picture frame of being launched comprises a clear to send message.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US47970103P | 2003-06-19 | 2003-06-19 | |
| US60/479,701 | 2003-06-19 | ||
| US10/870,718 | 2004-06-17 |
Publications (1)
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| CN1817053A true CN1817053A (en) | 2006-08-09 |
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Family Applications (4)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2004800169940A Pending CN1809976A (en) | 2003-06-19 | 2004-06-18 | Antenna steering for an access point based upon spatial diversity |
| CNB2004800171353A Expired - Fee Related CN100438348C (en) | 2003-06-19 | 2004-06-18 | Antenna steering and hidden node recognition for an access point |
| CNB2004800169921A Expired - Fee Related CN100481743C (en) | 2003-06-19 | 2004-06-18 | Access point of wireless local network, and operation method thereof |
| CNA2004800171796A Pending CN1817053A (en) | 2003-06-19 | 2004-06-18 | Antenna steering for an access point based upon probe signals |
Family Applications Before (3)
| Application Number | Title | Priority Date | Filing Date |
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| CNA2004800169940A Pending CN1809976A (en) | 2003-06-19 | 2004-06-18 | Antenna steering for an access point based upon spatial diversity |
| CNB2004800171353A Expired - Fee Related CN100438348C (en) | 2003-06-19 | 2004-06-18 | Antenna steering and hidden node recognition for an access point |
| CNB2004800169921A Expired - Fee Related CN100481743C (en) | 2003-06-19 | 2004-06-18 | Access point of wireless local network, and operation method thereof |
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| CN (4) | CN1809976A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103346826A (en) * | 2013-06-27 | 2013-10-09 | 福建星网锐捷网络有限公司 | Method for selecting intelligent antenna and access point |
| CN111525281A (en) * | 2020-04-07 | 2020-08-11 | 普联技术有限公司 | Intelligent antenna device |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7769348B2 (en) * | 2006-11-24 | 2010-08-03 | Sony Ericsson Mobile Communications Ab | Ad-hoc connectivity system and method |
| ATE504984T1 (en) * | 2007-02-07 | 2011-04-15 | Sony Deutschland Gmbh | METHOD FOR SENDING A SIGNAL IN A WIRELESS COMMUNICATIONS SYSTEM AND COMMUNICATIONS SYSTEM |
| EP2111068B1 (en) * | 2008-04-14 | 2014-01-01 | Alcatel Lucent | A picocell base station for wireless telecommunications providing radio coverage lobes as well as a method of identifying which subset of the lobes covers a user terminal |
| EP3185437B1 (en) * | 2014-08-24 | 2019-08-21 | LG Electronics Inc. | Method for determining weight for beamforming in wireless communication system and apparatus therefor |
| CN105142179B (en) * | 2015-06-12 | 2021-04-06 | 中兴通讯股份有限公司 | Wireless local area network access method and wireless access point |
| CN113259923B (en) * | 2021-07-05 | 2021-09-24 | 军事科学院***工程研究院网络信息研究所 | Directional beam detection method, tracking method, detection system and storage medium |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1202587B1 (en) * | 2000-10-31 | 2004-12-15 | Kabushiki Kaisha Toshiba | Wireless communication system, weight control apparatus, and weight vector generation method |
| US7519030B2 (en) * | 2001-11-19 | 2009-04-14 | At&T Intellectual Property Ii, L.P. | Adaptive MAC fragmentation and rate selection for 802.11 wireless networks |
-
2004
- 2004-06-18 CN CNA2004800169940A patent/CN1809976A/en active Pending
- 2004-06-18 CN CNB2004800171353A patent/CN100438348C/en not_active Expired - Fee Related
- 2004-06-18 CN CNB2004800169921A patent/CN100481743C/en not_active Expired - Fee Related
- 2004-06-18 CN CNA2004800171796A patent/CN1817053A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103346826A (en) * | 2013-06-27 | 2013-10-09 | 福建星网锐捷网络有限公司 | Method for selecting intelligent antenna and access point |
| CN103346826B (en) * | 2013-06-27 | 2016-06-29 | 福建星网锐捷网络有限公司 | The system of selection of smart antenna and access point |
| CN111525281A (en) * | 2020-04-07 | 2020-08-11 | 普联技术有限公司 | Intelligent antenna device |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100438348C (en) | 2008-11-26 |
| CN1809976A (en) | 2006-07-26 |
| CN100481743C (en) | 2009-04-22 |
| CN1809964A (en) | 2006-07-26 |
| CN1809968A (en) | 2006-07-26 |
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