WO2013062586A1 - Procédure de sondage pour réseaux sans fil - Google Patents
Procédure de sondage pour réseaux sans fil Download PDFInfo
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- WO2013062586A1 WO2013062586A1 PCT/US2011/058361 US2011058361W WO2013062586A1 WO 2013062586 A1 WO2013062586 A1 WO 2013062586A1 US 2011058361 W US2011058361 W US 2011058361W WO 2013062586 A1 WO2013062586 A1 WO 2013062586A1
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- 238000000034 method Methods 0.000 title claims abstract description 47
- 230000004044 response Effects 0.000 claims abstract description 180
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- 238000012545 processing Methods 0.000 claims description 10
- 230000008569 process Effects 0.000 description 21
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Classifications
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W76/00—Connection management
- H04W76/10—Connection setup
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W48/00—Access restriction; Network selection; Access point selection
- H04W48/08—Access restriction or access information delivery, e.g. discovery data delivery
- H04W48/14—Access restriction or access information delivery, e.g. discovery data delivery using user query or user detection
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W8/00—Network data management
- H04W8/005—Discovery of network devices, e.g. terminals
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W84/00—Network topologies
- H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
- H04W84/10—Small scale networks; Flat hierarchical networks
- H04W84/12—WLAN [Wireless Local Area Networks]
Definitions
- the invention relates to the field of radio communications and, particularly, to probing before connection establishment.
- Fast link setup is a desired feature in wireless networks.
- a wireless device Before a connection establishment, a wireless device may scan for another wireless device with which to establish the connection. This scanning procedure should be optimized so as to discover the candidate(s) for a connection establishment rapidly without excessive signalling overhead in a radio interface.
- Figure 1 illustrates a wireless communication scenario to which embodiments of the invention may be applied
- FIGS. 2 and 3 illustrate signalling diagrams of processes for active scanning according to some embodiments of the invention
- Figure 4 illustrates an embodiment of a structure of a shortened response message used in the active scanning
- Figure 5 illustrates a signalling diagram of a process for identifying a selected responding wireless device according to some embodiments of the invention
- Figures 6 and 7 illustrate structures of wireless apparatuses according to some embodiments of the invention.
- FIG. 1 illustrates groups of wireless communication devices forming wireless networks that may be referred to as basic service sets (BSS).
- BSS may be defined by a group of wireless communication devices comprising an access point (AP) 104, 108, 110 and one or more terminal stations (STA) 112, 114, 116 communicating with the access points 104, 108, 110 of their respective groups.
- a basic service set (BSS) is a basic building block of an IEEE 802.11 wireless local area network (WLAN), and it may have a determined coverage area 100, 102, 106 defined by the coverage area of the AP, for example.
- WLAN wireless local area network
- the most common BSS type is an infrastructure BSS that includes a single AP together with all associated, non-access-point STAs.
- the AP may be a fixed AP as AP 104, 110, or it may be a mobile AP as AP 108.
- the APs 104, 108, 110 may also provide access to other networks, e.g. the Internet.
- at least one of the BSSs is an independent BSS (IBSS) or a mesh BSS (MBSS) without a dedicated AP, e.g. the communication device 108 may in such an embodiment be a non-access-point terminal station.
- IBSS independent BSS
- MBSS mesh BSS
- WiMAX Worldwide Interoperability for Microwave Access
- UMTS LTE Long-term Evolution for Universal Mobile Telecommunication System
- cognitive radio features e.g. transmission medium sensing features and adaptiveness to coexist with radio access networks based on different specifications and/or standards.
- the BSSs are represented by the APs and/or STAs connected to each other, thereby establishing a BSS. Any one of the STAs 112, 114, 116 may establish a connection to any one of the BSSs, provided that the BSSs do not exclude the STAs from their list of devices allowed to connect to the BSSs, e.g. through shared key processes,.
- the connection establishment may include authentication in which an identity of a STA is established in the AP.
- the authentication may comprise exchanging an encryption key used in the BSS.
- the AP and the STA may carry out association in which the STA is fully registered in the BSS, e.g. by providing the STA with an association identifier (AID) for frame transmissions.
- the STA 112 may establish a connection to any one of the APs 104, 108, 110.
- the 802.11 ⁇ specifies a data transmission mode in which a STA can have oniy one secondary channel which results in a maximum bandwidth of 40 MHz.
- the primary channel is used in all transmissions, and with associated devices supporting only the 20 MHz mode.
- the secondary channel may be used with clients supporting wider transmission bandwidths, wherein the primary channel communication is extended by using the secondary channel as additional bandwidth.
- a further definition in 802.11 ⁇ is that the primary and secondary channels are adjacent.
- IEEE 802.11ac task group is developing an extension with a data transmission model to provide for wider bandwidths by increasing the number of secondary channels from 1 up to 7, thus resulting in bandwidths of 20 MHz, 40 MHz, 80 MHz, and 160 MHz.
- the primary channel may be used for connection establishment leading to association between two wireless apparatuses between which the connection is to be established.
- a wireless apparatus preparing for the association may scan for channels in order to detect a signal indicating presence of another wireless apparatus for association.
- the wireless apparatus may be in a completely unassociated state or it may have at least one existing association while seeking for a new association.
- IEEE 802.11 network discovery mechanisms define two modes: passive and active scanning. In the passive scanning, the wireless apparatus scans a channel for a determined period of time. If a wireless network is discovered, the wireless apparatus may proceed to connection establishment or, otherwise, it tunes to another channel.
- the wireless apparatus may scan for beacon frames or any other frames originated from any AP or that are destined to any AP or, alternatively, frames that meet given criteria e.g.
- the wireless apparatus uses the active scanning, it generates probe request frames and transmits them to request APs or, in general, other wireless apparatuses to reply with probe response frames.
- the rules applied to the scanning device (e.g. a STA) and the responding device (e.g. an AP) during the active scanning may be defined as follows.
- the scanning device may transmit one or more probe request frames comprising a service set identifier (SSID) field and/or a BSS identifier field specifying condition(s) as to which wireless apparatus should respond to the probe request.
- the scanning device may also reset a probe timer to zero and start it upon transmitting the probe request.
- the scanning device If the scanning device detects no signal with sufficiently high energy on the channel on which the probe request was transmitted before the probe timer reaches a minimum probe response time, it tunes to a next channel if any. Otherwise, the scanning device may wait on the channel until the probe timer reaches a maximum probe response time and, thereafter, the scanning device processes all received probe responses. Optionally, the scanning device may then tune to scan the next channel, if any.
- the probing procedure provides the scanning device with information on the wireless networks present in the area and, as a consequence, enables the scanning device to select a wireless network with which to establish a connection.
- the responding device receiving the probe request may respond with a probe response if an address 1 field in the probe request frame is a broadcast address or an individual medium access control (MAC) address of the responding device, if the SSID in the probe request is a so-called wildcard SSID, the SSID in the probe request is the specific SSID of the responding device, or the specific SSID of the responding device is included in an SSID list element of the probe request, or the specific Mesh ID in the probe request is the specific Mesh ID of the responding device, or an address 3 field in the probe request is a wildcard BSSID, or the BSSID of the responding device, or the MAC address of the peer device in mesh BSS. Further conditions for responding to the probe request may also be set. In general, the probe request specifies the conditions defining the devices that should respond with the probe response. All devices that fulfil the conditions may attempt to transmit the probe response frame.
- MAC medium access control
- Figure 2 illustrates a signalling diagram of an embodiment of such a method which comprises features in one wireless apparatus denoted by a requesting device in Figure 2 and in at least one other wireless apparatus denoted by a responding device or a responder as in Figure 2.
- a requesting device is scanning for presence of wireless networks in its vicinity.
- the requesting device may employ an active scanning procedure as follows.
- the requesting device transmits a first request message comprising an information element requesting at least one responding wireless apparatus to transmit a response message of a first type as a response to the first request message.
- the response message of the first type as a shortened response message below.
- At least two responding devices (Responder 1 and Responder 2) acquire the first request message originated from the requesting device, in respective blocks 202 and 204, the responding devices process the request message so as to determine whether the conditions specified in the request message oblige them to respond to the request message. Let us assume that they both are obliged to respond to the request message and, as a consequence, they determine to respond to the first request message and transmit a shortened response message to the requesting device in respective blocks 202, 204.
- the first shortened response may be transmitted within the minimum response time specifying a time limit configuring the requesting device to tune to another channel, if it receives no responses.
- the other shortened response messages may be transmitted within a maximum response time.
- the requesting device acquires the at least two shortened response messages originated from the responding devices.
- the requesting device processes the received shortened response messages and selects at least one responding device.
- the selected device may form a subset of a group comprising said at least two different responding wireless apparatuses from which the shortened response message has been received. In other words, the requesting device may select only some of the responding devices, not necessary all of them.
- the requesting device transmits a second request message to the selected at least one responding wireless apparatus, wherein the second request message comprises an information element causing the at least one selected responding apparatus to transmit a response message of a second type as a response to the second request message.
- the response message of the second type may contain more information on the wireless network of the responding device than the shortened response message, while the shortened response message contains a limited amount of information on the network compared with the detailed response message.
- the second request message may differ from the first request message in that the second request message may configure a different set of responding devices to respond, wherein the different set is the subset of a set of responding device configured by the first request message to respond. New minimum and maximum response times may be applied to the second request message.
- the second request message (block 208) is transmitted within the maximum response time of the first request message.
- the responding devices acquire the second request message and process it so as to determine whether or not to respond, in block 210, the second responding device (Responder 2) processes said information element identifying the selected at least one responding wireless apparatus and determines whether or not to respond to the second request message. Let us assume that the second request message indicates that the second responding device is not configured to respond and, therefore, the second responding device prevents the response in block 210.
- the first responding device (Responder 1) processes said information element identifying the selected at least one responding wireless apparatus and determines whether or not to respond to the second request message. Let us assume that the second request message indicates that the first responding device is configured to respond and, upon determining to respond, the first responding device transmits the detailed response message to the requesting device.
- the requesting device acquires said detailed response message originated from the selected responding wireless apparatus and, optionally, acknowledges the reception of the detailed response message in block 214. Thereafter, the requesting device may start connection establishment with the first responding device in 216 on the basis of the detailed response message.
- the shortened response message transmitted in blocks 202, 204 may be shorter than the detailed response message of block 212.
- the shortened response message does not contain medium access control (MAC) data, while the detailed response message contains the MAC data.
- the null data packet may comprise a physical layer convergence protocol (PLCP) header.
- PLCP physical layer convergence protocol
- PSDU physical service data unit
- the probe response message is a relatively long message that is typically transmitted with a robust modulation and coding scheme, and the reduction in the number of the transmitted probe responses improves the spectral efficiency.
- the shortened response message may be seen as a type of "Hello" message which merely indicates the present wireless networks but does not necessarily contain sufficient information needed for the connection establishment.
- the shortened response message may comprise an identifier of the wireless network or other information enabling the identification of the wireless network in the selection block 206.
- the detailed response message may then contain characteristics of the responding device, e.g. beacon interval, capability information, SSID, supported data rates, and/or other information needed to identify the responding device as a candidate for the actual connection establishment.
- the request messages are both probe request messages, wherein the second request message may comprise an additional field comprising at least one information element specifying the selected responding device(s).
- the shortened response message may be a null data packet which may also have another use purpose in the wireless network(s).
- the null data packet may be used in estimation of channel state for multi-antenna transmission, e.g. beamforming.
- the null data packet may be used for the channel estimation when the requesting device is in a connected state, while the null data packet may be used as the above-mentioned shortened response message when the requesting device is in an unconnected state.
- the requesting device may, however, perform channel estimation, e.g.
- the requesting device may select the wireless network providing the best channel quality, e.g. the lowest path loss estimate. It should be noted that the selection may equally be based on other criteria.
- the request message is a generic advertising service (GAS) request message
- a corresponding detailed response message may be a GAS response message.
- GAS provides for Layer 2 transport of advertisement protocol frames between a mobile device (ST A) and a server in the network prior to authentication.
- An AP may be responsible for relaying a STA's query to a server in the carrier's network and for delivering the server's response back to the STA.
- the request-response process may be carried out between a STA and the AP or between the STA and the server via an AP.
- the server may function as the above-described responding device.
- the shortened response message may be the null data packet in this embodiment, too.
- the request messages are new types of messages and let us denote them as Null Data Packet (NDP) Scan (NSCAN) requests.
- NDP Null Data Packet
- NSCAN Null Data Packet
- the NSCAN request may have a structure similar to that of a probe request or another conventional request message, but it may include an additional field comprising an information element used for indicating whether a shortened response message or a detailed response message is requested by the requesting device.
- the information element is one bit.
- the information element may have a first value (e.g. a bit value 1) for the shortened response message and another value (e.g. a bit value 0), or the field may even be omitted, for the detailed response message.
- the NSCAN request may comprise an information element identifying the NSCAN request as an action management frame having a unique type. This information element may specify the frame to be the NSCAN request.
- Figure 3 illustrates an embodiment where the request message is a conventional probe request message comprising the above-mentioned additional information element. Additionally, the signalling diagram shows an embodiment of the operation of a conventional (legacy) device not supporting the shortened response messages.
- the requesting device transmits in block 300 the first request message which may be the probe request message comprising an information element used for indicating whether a shortened response message or a detailed response message is requested by the requesting device.
- the requesting device may be configured to request for the shortened response.
- the first responding device (Responder 1) is a wireless apparatus that is able to discriminate the additional information element in the probe request
- the second responding device (Responder 2) is a legacy device not supporting the new information element requests. Therefore, the legacy devices may be configured to ignore the new information element and to respond with a conventional probe response. Accordingly, this ensures operation of the embodiment when the wireless networks comprise both legacy devices and devices supporting the shortened responses.
- both responding devices receive the first probe request and determine to respond.
- the first responding device gains the access to the channel first, e.g. through channel contention, and transmits the shortened response message, e.g. the null data packet, in block 202 in the above- described manner.
- There may be a guard period e.g. a distributed coordination function inter-frame space (DIFS), and a backoff computation between the end of the probe request and the beginning of the null data packet transmission.
- DIFS distributed coordination function inter-frame space
- the requesting device may acknowledge the null data packet by transmitting another null data packet in block 302.
- the null data packet transmitted as the acknowledgment may have the same format as the null data packet transmitted by the responding device in block 202.
- Table 1 below shows an embodiment of an orthogonal frequency division multiplexing (OFDM) null data packet that may be used as the acknowledging null data packet in a wireless network based on IEEE 802.11.
- OFDM orthogonal frequency division multiplexing
- the acknowledging null data packet may comprise a legacy short training field (L-STF), a legacy long training field (L-STF), legacy signal (L-SIG) field, and they may comprise the same contents as specified in the IEEE 802.11.
- L-STF legacy short training field
- L-STF legacy long training field
- L-SIG legacy signal
- Table 2 shows an embodiment of the L-SIG field.
- the Rate and Length fields may be set to 0 in an OFDM NDP.
- the acknowledgment may be carried out without the need for the payload, i.e. MAC headers or data.
- a guard period e.g. a short inter-frame space (SIFS)
- SIFS short inter-frame space
- the second responding device may gain access to the channel to transmit the response message in block 304, e.g. after another guard period which may be a point coordination function inter-frame space (PIFS).
- PIFS point coordination function inter-frame space
- This response message may be the detailed response message, e.g. the probe response message, as the legacy device did not recognize the request for the shortened response message in the first probe request message.
- the requesting device may acknowledge the reception of the detailed response message by transmitting a conventional acknowledgment message in block 306.
- the requesting device may carry out the selection of the wireless network in block 206, and the process may proceed in the above-described manner.
- Figure 4 illustrates an embodiment of the structure of the null data packet.
- the null data packet in the present embodiment comprises a legacy short training field (L-STF), a legacy long training field (L-.LTF), legacy signal (L-SIG) field, a very high throughput signal (VHT-SIG) A field, a very high throughput short training field (VHT-STF), a very high throughput long training field (VHT-LTF), and very high throughput signal (VHT-SIG) B field.
- L-STF legacy short training field
- L-.LTF legacy long training field
- L-SIG legacy signal
- VHT-SIG very high throughput signal
- VHT-SIG very high throughput signal
- VHT-SIG very high throughput signal
- VHT-SIG very high throughput signal
- VHT-SIG A or VHT-SIG B may be changed to identify that the null data packet is the shortened response message or the conventional null data packet used for channel estimation, for example.
- one bit value in VHT-SIG B field may be changed to realize this, e.g. the value of bit 4, as shown in Tables 3 and 4 below.
- Table 3 shows the bit values of the VHT-SIG B field for the conventional null data packet
- Table 4 shows the bit values of the VHT-SIG B field for the shortened response message.
- a high throughput signal (HT-SIG) field of the null data packet frames may be arranged to comprise an information element discriminating the null data packet used for the channel estimation from the shortened response message.
- the HT-SIG field may comprise a "Not Sounding" field or another corresponding field defining whether or not the null data packet relates to the channel sounding or to the shortened response.
- the reserved bit below the "Not Sounding” field may be used to discriminate the shortened response (block 202) and the acknowledging null data packet frame (block 302).
- the reserved field may be set to bit value 1 for the shortened response (block 202) and to bit value 0 for the acknowledging null data packet (block 302).
- the second request message may comprise an information element comprising the identifier of the selected responding device, thereby specifying the responding device that should respond with the detailed response message.
- the selected responding device may be specified in the second request message by reference to a timing of the shortened response message transmitted by the selected responding device.
- the timing of the shortened response message is used as means for identifying the selected responding device with reference to a signalling diagram of Figure 5.
- the requesting device transmits the first request message, as described above, thereby requesting for shortened response messages.
- Figure illustrates the communication only between the requesting device and the first responding device for the sake of simplicity. Other devices may naturally also respond to the first request message.
- the first responding device Upon reception of the first request message and upon determining to respond to the first request message with the shortened response message, the first responding device (Responder 1) prepares the shortened response message, e.g. the null data packet, in block 502 and transmits it to the requesting device. Additionally, the first responding device may store a timing of the shortened response message, e.g. its transmission timing. Then, the requesting device selects the responding device (Responder 1) in block 206 in the above-described manner and transmits the second request message in block 504, thereby configuring the first responding device to transmit the detailed response message.
- the responding device selects the responding device (Responder 1) in block 206 in the above-described manner and transmits the second request message in block 504, thereby configuring the first responding device to transmit the detailed response message.
- the requesting device may insert in the second request message a time reference related to the timing of the shortened response message.
- the time reference may be derived from the timing of the shortened response message so as to enable the responding device to determine that it should transmit the detailed response message.
- the time reference included in the second request message is reception timing of the shortened response message in the requesting device.
- devices of an IEEE 802.11 based system are synchronized to a common reference clock, e.g. GPS (Global Positioning System) time and, thus, the requesting device and the responding devices have the same system clock.
- the reception timing is relatively close to the transmission timing and, thus, enables matching them with each other in the first responding device.
- the reception timing may relate to the start or to the end of the reception of the shortened response message.
- the timing stored by the responding device may relate to the start or to the end of the transmission of the shortened response message. Providing the actual timing may require adding many bits in the second request message.
- the time reference included in the second request message is a timing offset related to the shortened response message.
- Figure 5 illustrates two embodiments for the timing offset.
- the timing offset is a time difference between the first request message and the short response message denoted by T1 in Figure 5.
- the responding device may be configured to store the reception timing of the first request message so as to derive T .
- the timing offset is a time difference between the second request message and the short response message denoted by T2 in Figure 5.
- the offset may be specified in determined time units, e.g. in increments of 32 ps. As a consequence, the number of bits needed to specify the time reference may be reduced with respect to reporting the absolute time.
- Tabie 6 shows an embodiment of some of the fields of the second request message, wherein the fields may collectively be referred to as null data packet (NDP)
- NDP null data packet
- the transmitter address may be set to the MAC address of the requesting device which is the transmitter of the first request message.
- the length of the field may be 6 octets.
- the Sequence Control field may specify a sequence number of the first request message. Each request message or active scanning procedure may be associated with the sequence number, so the Sequence Control field enables the responding device to determine the request message the second request message relates to.
- the Timing Offset field may specify the above-mentioned timing offset T1 or T2, for example. Otherwise, the second request message may comprise the same parameters as the first request message, e.g. it may define the same conditions for the responding device as the first request message. The timing offset may be used to further narrow the responding devices to one (or more).
- Block 506 may comprise determining the conditions that were determined from the first request message. Additionally, block 506 may comprise extracting the Timing Offset field and comparing the value of the Timing Offset field with a timing stored in the responding device. For example, if the system uses the timing offset T1 , the responding device has stored the time offset between the reception of the first request message and the transmission of the shortened response message.
- the responding device has stored the time offset between the reception of the second request message and the transmission of the shortened response message.
- the responding device may apply some tolerance so as to account for the system clock drift between the requesting device and the responding device, processing time, channel propagation time, etc.
- both the requesting device and the responding device may be configured to use the same timing instance of the first request message, the shortened response message and/or the second request message, e.g. the start or the end of the transmission/reception of the message.
- the responding device Upon detecting that the stored time offset provides a sufficient match with the timing offset included in the second request message, the responding device determines that it is requested to respond to the second request message with the detailed response message. As a consequence, the responding device may proceed to block 212.
- Figure 6 illustrates an embodiment of an apparatus comprising means for carrying out the above-mentioned functionalities of the wireless apparatus configured to process received request messages and respond to then, if applicable.
- the apparatus of Figure 6 may thus be considered as a structural embodiment of the above-mentioned responding device.
- the apparatus may be a communication apparatus of an IEEE 802.11 network or another wireless network, e.g. an AP.
- the apparatus may be a computer (PC), a laptop, a tablet computer, a cellular phone, a palm computer, a fixed base station operating as the AP, or any other apparatus provided with radio communication capability.
- the apparatus is comprised in such a communication apparatus, e.g. the apparatus may comprise a physical circuitry, e.g. a chip, a processor, a micro controller, or a combination of such circuitries in the communication apparatus.
- the apparatus may comprise a communication controller circuitry 10 configured to control the communications in the communication apparatus.
- the communication controller circuitry 10 may comprise a control part 12 handling control signalling communication with respect to transmission, reception, and extraction of control frames including the request messages, the response messages, and the acknowledgment messages, as described above.
- the communication controller circuitry 10 may further comprise a data part 16 that handles transmission and reception of payload data during transmission opportunities of the communication apparatuses (transmission) or transmission opportunities of other communication apparatuses (reception).
- the communication controller circuitry 10 may further comprise a request processor 14 configured to carry out at least some of the request processing procedures described above.
- the request processor 14 may acquire a request message through the control part 12 and to process the request message so as to determine whether or not to respond to the request and the type of the response message to be used.
- the request processor 14 Upon determining that the request should be responded, the request processor 14 is configured to start the preparation of either the shortened response message or the detailed response message, as described above.
- the communication control circuitry 10 may further comprise a timer 18 configured to keep track of the system time.
- the request processor 14 may be configured to store the timing of at least the transmitted shortened response messages, and the timing may be acquired from the timer 18 in connection with the transmission of the shortened response messages. The timing may then be stored in a memory unit 20.
- the circuitries 12 to 18 of the communication controller circuitry 10 may be carried out by the one or more physical circuitries or processors. In practice, the different circuitries may be realized by different computer program modules. Depending on the specifications and the design of the apparatus, the apparatus may comprise some of the circuitries 12 to 18 or all of them.
- the memory 20 may further store computer programs (software) configuring the apparatus to perform the above-described functionalities of the communication apparatus.
- the memory 20 may also store communication parameters and other information needed for the wireless communications, e.g. the stored timings of the request/response messages.
- the apparatus may further comprise radio interface components 22 providing the apparatus with radio communication capabilities within its wireless network and/or with other wireless networks.
- the radio interface components 22 may comprise standard well-known components such as amplifier, filter, frequency-converter, (de)modulator, and encoder/decoder circuitries and one or more antennas.
- the apparatus may further comprise a user interface enabling interaction with the user of the communication device.
- the user interface may comprise a display, a keypad or a keyboard, a loudspeaker, etc.
- the apparatus carrying out the embodiments of the invention in the communication apparatus comprises at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to carry out the functionality of the responding device in any one of the processes of Figures 2 to 5.
- the at ieast one processor, the memory, and the computer program code form processing means for carrying out embodiments of the present invention in the wireless communication apparatus processing request messages.
- Figure 7 illustrates an embodiment of an apparatus comprising means for carrying out the above-mentioned functionalities of the wireless apparatus configured to carry out an active scanning process involving transmission of request messages and response messages.
- the apparatus may be a communication apparatus of an IEEE 802.11 network or another wireless network, e.g. a STA.
- the apparatus may be a computer (PC), a laptop, a tablet computer, a cellular phone, a palm computer, or any other apparatus provided with radio communication capability.
- the apparatus is comprised in such a communication apparatus, e.g. the apparatus may comprise a physical circuitry, e.g. a chip, a processor, a micro controller, or a combination of such circuitries in the communication apparatus.
- the apparatus may comprise a communication controller circuitry 50 configured to control the communications in the communication apparatus.
- the communication controller circuitry 50 may comprise a control part 52 handling control signalling communication with respect to transmission, reception, and extraction of control frames including the request messages, the response messages, and the acknowledgment messages, as described above.
- the communication controller circuitry 50 may further comprise a data part 56 that handles transmission and reception of payload data during transmission opportunities of the communication apparatuses (transmission) or transmission opportunities of other communication apparatuses (reception).
- the communication controller circuitry 50 may further comprise a probing controller 54 configured to carry out active scanning procedures in the above-mentioned requesting device.
- the probing controller 54 may process and transmit the request message through the control part 52 as a part of the active probing procedure and to process any response message received as a response to the request message(s).
- the probing controller 54 may be configured to request a first set of responding devices to respond to a first request message with a shortened response message and, thereafter, the probing controller 54 may be configured to select a subset of responding devices to provide a detailed response to a second request message.
- the communication controller circuitry 50 may further comprise a timer 58 measuring the above-mentioned minimum and maximum response time and, in some embodiments, the timing of the shortened response message(s) and the timing of at least some of the request messages. The measured timings may be stored in a memory unit 60.
- the circuitries 52 to 58 of the communication controller circuitry 50 may be carried out by the one or more physical circuitries or processors. In practice, the different circuitries may be realized by different computer program modules. Depending on the specifications and the design of the apparatus, the apparatus may comprise some of the circuitries 52 to 58 or all of them.
- the apparatus may further comprise the memory 60 to store computer programs (software) configuring the apparatus to perform the above- described functionalities of the communication apparatus.
- the memory 60 may also store communication parameters and other information needed for the wireless communications, e.g. the timings of the received shortened response messages and, optionally, timing of at least one of the first request message and the second request message.
- the apparatus may further comprise radio interface components 62 providing the apparatus with radio communication capabilities within the BSS and/or with other BSSs.
- the radio interface components 62 may comprise standard well-known components such as amplifier, filter, frequency-converter, (de)modulator, and encoder/decoder circuitries and one or more antennas.
- the apparatus may further comprise a user interface enabling interaction with the user of the communication device.
- the user interface may comprise a display, a keypad or a keyboard, a loudspeaker, etc.
- the apparatus carrying out the embodiments of the invention in the communication apparatus comprises at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to carry out the functionality of the requesting device in any one of the processes of Figures 2 to 5.
- the at least one processor, the memory, and the computer program code form processing means for carrying out embodiments of the present invention in the apparatus functioning in the requesting device.
- circuitry refers to all of the following: (a) hardware-only circuit implementations, such as implementations in only analog and/or digital circuitry, and (b) to combinations of circuits and software (and/or firmware), such as (as applicable): (i) a combination of processor(s) or (ii) portions of processor(s)/software including digital signal processor(s), software, and memory(ies) that work together to cause an apparatus to perform various functions, and (c) to circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present.
- circuitry would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and/or firmware.
- circuitry would also cover, for example and if applicable to the particular element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in server, a cellular network device, or other network device.
- the processes or methods described in Figures 2 to 5 may also be carried out in the form of a computer process defined by a computer program.
- the computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of distributable or a non-distributable carrier, which may be any entity or device capable of carrying the program.
- Such carriers include a record medium, computer memory, readonly memory, electrical carrier signal, telecommunications signal, and software distribution package, for example.
- the computer program may be executed in a single electronic digital processing unit or it may be distributed amongst a number of processing units.
- the present invention is applicable to wireless networks defined above but also to other suitable communication systems.
- the invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.
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Abstract
L'invention concerne un procédé, un appareil et un programme informatique pour préparer l'établissement d'une connexion. La préparation consiste à demander une transmission d'un message de réponse raccourci depuis un premier ensemble de dispositifs de réponse. Lors de la réception des messages de réponse raccourcis, un sous-ensemble des dispositifs de réponse peut être choisi, et on demande aux dispositifs de réponse choisis de transmettre un message de réponse détaillé qui peut servir de base pour l'établissement de la connexion.
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PCT/US2011/058361 WO2013062586A1 (fr) | 2011-10-28 | 2011-10-28 | Procédure de sondage pour réseaux sans fil |
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PCT/US2011/058361 WO2013062586A1 (fr) | 2011-10-28 | 2011-10-28 | Procédure de sondage pour réseaux sans fil |
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Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20140247746A1 (en) * | 2011-11-07 | 2014-09-04 | Lg Electronics Inc. | Link adaptation and device in active scanning method |
US20140355462A1 (en) * | 2013-05-30 | 2014-12-04 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (rtt) exchange |
CN105684520A (zh) * | 2013-08-30 | 2016-06-15 | 三星电子株式会社 | 用于建立无线局域网通信连接的方法及其电子设备 |
WO2017041629A1 (fr) * | 2015-09-09 | 2017-03-16 | 华为技术有限公司 | Procédé de traitement par balayage actif et dispositif associé, et système de communication |
WO2017172187A1 (fr) * | 2016-03-31 | 2017-10-05 | Intel IP Corporation | Prise en charge de ssid caché dans des réseaux dmg |
US10015736B2 (en) | 2012-06-18 | 2018-07-03 | Nokia Technologies Oy | Scanning by determining an access point based on received downlink frames |
EP3487231A1 (fr) * | 2012-05-08 | 2019-05-22 | Electronics and Telecommunications Research Institute | Procédé de balayage dans un système de réseau local sans fil et dispositif de prise en charge associé |
EP3468244A4 (fr) * | 2016-12-07 | 2019-07-03 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Procédé de traitement d'informations et dispositif terminal |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030083015A1 (en) * | 2001-10-26 | 2003-05-01 | Arto Palin | Accelerating a set-up procedure for wireless connections between devices |
US20070191033A1 (en) * | 2006-02-16 | 2007-08-16 | Softwired Ag | Scalable wireless messaging system |
US20090003275A1 (en) * | 2003-09-17 | 2009-01-01 | Research In Motion Limited | System and Method for Asynchronous Wireless Services Using Reverse Service Schema Generation |
-
2011
- 2011-10-28 WO PCT/US2011/058361 patent/WO2013062586A1/fr active Application Filing
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20030083015A1 (en) * | 2001-10-26 | 2003-05-01 | Arto Palin | Accelerating a set-up procedure for wireless connections between devices |
US20090003275A1 (en) * | 2003-09-17 | 2009-01-01 | Research In Motion Limited | System and Method for Asynchronous Wireless Services Using Reverse Service Schema Generation |
US20070191033A1 (en) * | 2006-02-16 | 2007-08-16 | Softwired Ag | Scalable wireless messaging system |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9781615B2 (en) * | 2011-11-07 | 2017-10-03 | Lg Electronics Inc. | Link adaptation and device in active scanning method |
US20140247746A1 (en) * | 2011-11-07 | 2014-09-04 | Lg Electronics Inc. | Link adaptation and device in active scanning method |
EP3487231A1 (fr) * | 2012-05-08 | 2019-05-22 | Electronics and Telecommunications Research Institute | Procédé de balayage dans un système de réseau local sans fil et dispositif de prise en charge associé |
US10716055B2 (en) | 2012-05-08 | 2020-07-14 | Electronics And Telecommunications Research Institute | Scanning method in wireless LAN system and supporting device therefor |
US11218953B2 (en) | 2012-05-08 | 2022-01-04 | Electronics And Telecommunications Research Institute | Scanning method in wireless LAN system and supporting device therefor |
US10015736B2 (en) | 2012-06-18 | 2018-07-03 | Nokia Technologies Oy | Scanning by determining an access point based on received downlink frames |
US10129120B2 (en) | 2013-05-30 | 2018-11-13 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (RTT) exchange |
US9699052B2 (en) | 2013-05-30 | 2017-07-04 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (RTT) exchange |
US9923792B2 (en) | 2013-05-30 | 2018-03-20 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (RTT) exchange |
US9459337B2 (en) | 2013-05-30 | 2016-10-04 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (RTT) exchange |
US20190052557A1 (en) * | 2013-05-30 | 2019-02-14 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (rtt) exchange |
US20140355462A1 (en) * | 2013-05-30 | 2014-12-04 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (rtt) exchange |
US10637759B2 (en) | 2013-05-30 | 2020-04-28 | Qualcomm Incorporated | Methods and systems for enhanced round trip time (RTT) exchange |
EP3041292A4 (fr) * | 2013-08-30 | 2017-01-18 | Samsung Electronics Co., Ltd. | Procédé pour établir une connexion de communication de réseau local sans fil et dispositif électronique à cet effet |
CN105684520A (zh) * | 2013-08-30 | 2016-06-15 | 三星电子株式会社 | 用于建立无线局域网通信连接的方法及其电子设备 |
US10624022B2 (en) | 2013-08-30 | 2020-04-14 | Samsung Electronics Co., Ltd. | Method for establishing wireless LAN communication connection and electronic device therefor |
WO2017041629A1 (fr) * | 2015-09-09 | 2017-03-16 | 华为技术有限公司 | Procédé de traitement par balayage actif et dispositif associé, et système de communication |
US10057357B2 (en) | 2016-03-31 | 2018-08-21 | Intel IP Corporation | Support for hidden SSID in DMG networks |
WO2017172187A1 (fr) * | 2016-03-31 | 2017-10-05 | Intel IP Corporation | Prise en charge de ssid caché dans des réseaux dmg |
EP3468244A4 (fr) * | 2016-12-07 | 2019-07-03 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Procédé de traitement d'informations et dispositif terminal |
US10813058B2 (en) | 2016-12-07 | 2020-10-20 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Method for processing information and terminal device |
US10813057B2 (en) | 2016-12-07 | 2020-10-20 | Guangdong Oppo Mobile Telecommunications Corp., Ltd. | Method for processing information and terminal device |
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