JP5931917B2 - LTE / WI-FI coexistence - Google Patents

Description

  The present invention relates generally to wireless communication, and more particularly to coexistence between communication devices.

(Refer to related applications)
This application is a continuation of US patent application 11 / 647,122 (patent document 1) filed on December 27, 2006 and US patent application 12 / 426,251 filed on April 19, 2009 (patent document 2). Applications are hereby incorporated by reference. This application claims the benefit of US Provisional Application 61 / 430,193, filed January 6, 2011, which is hereby incorporated by reference.

  In a communication system, communication devices of different communication protocols operate close to each other and operate in adjacent or overlapping frequency bands. Due to the proximity of location and frequency, these systems are susceptible to interference.

  Various techniques are known in the prior art for coexistence between different communication protocols. For example, U.S. Patent No. 6,057,096, which is hereby incorporated by reference, establishes a first communication session on a first connection between a wireless terminal and a base station (BS) of a wide area wireless data network, and the session Discloses a communication method that operates according to a first protocol that defines a sequence of time frames. Based on a time frame defined by a base station (BS), a time slot is allocated to establish a second communication session on a second connection between the wireless terminal and a peripheral wireless device, The second session operates according to a second narrow time slot communication protocol that is different from the first protocol. In the time frame for communication on the first connection between the base station (BS) and the wireless terminal, a time interval is assigned, and the assigned time interval alternates with the assigned time slot; And there is no duplication. The first and second communication sessions are processed simultaneously in the assigned time interval and the designated time slot, respectively.

  U.S. Patent No. 6,057,056, which is incorporated herein by reference, includes assigning a time interval for a first communication session on a first connection between a wireless terminal and a base station of a wide area wireless data network, A communication method is described in which a first communication session operates according to a first protocol that defines a time frame, the time frame having a lower link subframe and an upper link subframe. A time slot is assigned to a second communication session on a second connection between the wireless terminal and the peripheral wireless device, the second communication session operates according to a second narrow time slot protocol, and the second protocol Is different from the first protocol and has a retransmission mechanism. The time slot is synchronized with the downlink and uplink subframes defined by the base station (BS). The operation of the second connection invokes the retransmission mechanism and causes the wireless terminal to transmit only during timeslots that do not overlap with the downlink subframe, so that several timeslots overlap with the downlink subframe. Is prohibited.

  U.S. Patent No. 6,057,056, which is hereby incorporated by reference, describes a communication device that includes at least one wireless receiver circuit. The circuit receives and downconverts the first and second radio signals, the radio signals are transmitted according to different first and second network protocols on different first and second radio networks, respectively. Thereby, the first and second down-converted signals are connected. The baseband processing circuit includes a processing element connected to receive the first and second downconverted signals and extract first and second data from the signals. The processing element has a first configuration for restoring the first down-converted signal according to the first network protocol, and a second configuration for restoring the second down-converted signal according to the second network protocol. And have.

  U.S. Pat. Nos. 6,028,038 and 6,086,096, which are hereby incorporated by reference, have the step of establishing a first connection between a wireless terminal and a base station of a wide area wireless data network, A communication method is described that operates according to a first protocol that defines a sequence of time frames for data transfer between a terminal and a base station. A signal is sent from the wireless terminal to the base station that identifies an interval that includes one or more time frames during which the wireless terminal does not receive data from the base station. During the interval, a second connection is established between the wireless terminal and one access point of the wireless LAN (WLAN) according to a second protocol different from the first protocol.

US patent application 11 / 647,122 US patent application 12 / 426,251 US Provisional Patent Application 61 / 430,193 US Patent Application Publication 2007/0275746 US Patent Application Publication 2009/0129367 US Patent 7,542,728 US Patent 7,545,787 US Patent Application Publication 2010/0142504

    One embodiment of the present invention described below provides a communication method in a wireless device. The method includes establishing a first connection with a base station (BS) of a wide area wireless data network and establishing a second connection over a wireless LAN (WLAN). In the wireless device, a time interval for communicating on the second connection is selected. In preparation for the selected time interval, by reporting to the base station (BS) that there is no data waiting to be transmitted from the wireless device prior to the time interval, the base station (BS) Refrain from scheduling data transmissions from the wireless device to the base station (BS) on one connection. During the time interval, the wireless device is used to communicate over a second connection over a wireless LAN (WLAN).

  In some embodiments, reporting that there is no data waiting to be transmitted causes the base station (BS) to schedule transmission of data awaiting transmission outside the time interval, so that some data may be transmitted to the base station ( Even when waiting for transmission to BS). In some embodiments, the method includes reporting to the base station (BS) that there is data waiting to be transmitted from the wireless device in preparation for the end of the time interval. Reporting the data waiting to be transmitted includes reporting a data amount different from the actual size of the data waiting to be transmitted in order to control the size of the scheduled transmission.

    In another embodiment, the wide area wireless data network operates according to the Long Term Evolution (LTE) standard, and reporting that there is no data waiting to be transmitted includes sending a buffer status report (BSR) message. In yet another embodiment, the first connection and the second are reported by alternately performing steps of reporting to the base station (BS) that there is data waiting to be transmitted and reporting that there is no data waiting to be transmitted. Applying a communication pattern that alternately uses connections. In some embodiments, the method includes prohibiting communication on the second connection before and after the selected time interval. Reporting to the base station (BS) includes sending a report message to the base station (BS) at a certain time considering the scheduling delay time (latency) of the first connection.

    According to another embodiment of the present invention, there is further provided a wireless device, wherein the radio frequency (RF) front end and the radio frequency (RF) front end are on a wide area wireless data network and a wireless LAN (WLAN). A baseband circuit configured to exchange RF signals for communication, the baseband circuit via a radio frequency (RF) front end, a base station (BS) on a wide area wireless data network A first connection, and a second connection over a wireless LAN (WLAN), selecting a time interval for communicating over the second connection, and in preparation for the selected time interval, a time interval Before the base station (BS) reports to the base station (BS) that there is no data waiting to be transmitted from the wireless device. To refrain from scheduling data transmissions from the device to the base station (BS) during the time interval, and during the time interval, use the wireless device on a second connection over the wireless LAN (WLAN). A wireless device is provided that is configured to communicate with each other.

  According to an embodiment of the present invention, a method of communication in a wireless device is also provided. The method includes alternating an upper link interval for transmission to a base station (BS) and a lower link interval for receiving from the base station (BS) a first connection with a base station (BS) of a wide area wireless data network. Establishing in the sequence; establishing in the wireless device simultaneously with the first connection a second connection with a wireless LAN (WLAN) station located proximate to the wireless device; and downlink time Interfering with the reception of the base station (BS) on the first connection from the transmission of the station on the second connection by sending a signal from the wireless device to the station to block the station from transmitting during the interval And a step of preventing.

  In an embodiment, the step of preventing interference comprises that the wireless device transmits to the station on the second connection to prevent the station from sending an acknowledgment message to the wireless device during the downlink time interval. Having a blocking step. In another embodiment, preventing interference includes sending a “CTS-to-self” message to the station. In the disclosed embodiment, preventing interference includes scheduling transmissions from the wireless device to the station such that each acknowledgment from the station occurs during an uplink interval of the first connection. . Scheduling transmissions may include setting respective transmission parameters such that acknowledgments occur during the upper link interval. The parameter may include the duration and / or start time of the transmission.

  In other embodiments, preventing interference comprises communicating with a station using a modulation and coding scheme (MCS) such that the transmission of the station falls outside the downlink interval. Selected. The method may comprise transmitting to a station using a modulation and coding scheme (MCS), the scheme comprising: a station on a second connection from a transmission of a wireless device on the first connection. Selected to take into account the interference to the reception.

  In some embodiments, the method includes transmitting an acknowledgment message to the station at a power level lower than a normal power level used for data transmission to the station, and the acknowledgment message to conform to the power level. Setting a modulation and coding scheme (MCS). In other embodiments, preventing interference includes transmitting the signal at a power level selected to block the station but avoid blocking other stations not in close proximity to the wireless device. In yet another embodiment, preventing interference includes synchronizing a time base of the second connection to a frame time base of the first connection at the wireless device.

  According to one embodiment of the present invention, a wireless device is provided that includes a radio frequency (RF) front end and a baseband circuit. The radio frequency (RF) front end is configured to exchange RF signals for communication over a wide area wireless data network and over a wireless LAN (WLAN). The baseband circuit communicates a first connection with a base station (BS) on a wide area wireless data network via a radio frequency (RF) front end and an uplink interval and base for transmission to the base station (BS). Established in an alternating sequence of down link intervals for receiving from a station (BS) and simultaneously establish a second connection with a wireless LAN (WLAN) station located close to the wireless device at the same time as the first connection. And the base station on the first connection from the transmission of the station on the second connection by sending a signal from the wireless device to the station to block the station from transmitting during the downlink time interval ( BS) is set to prevent interference with reception.

  According to an embodiment of the present invention, a method of communication in a wireless device is provided. The method establishes a first connection with a base station (BS) of a wide area wireless data network and establishes a second connection over a wireless LAN (WLAN) simultaneously with the first connection; Communicating on a first connection with a base station (BS) in a mode in which a pattern of activation periods and deactivation periods is preset. In order to reduce interference between the first connection and the second connection, transmission on the second connection is based on a pattern of activation and deactivation periods preset for the first connection. Is set.

  In some embodiments, the first connection operates according to the Long Term Evolution (LTE) standard, and the mode includes semi-persistent scheduling (SPS) and / or discontinuous reception (DRX). In some embodiments, setting up the transmission includes preventing transmission on the second connection from occurring during the activation period of the first connection. In other embodiments, setting up the transmission includes controlling the transmission of the wireless device over the second connection.

  In the disclosed embodiment, setting up transmission includes controlling transmission of opposing endpoints with which the wireless device communicates over the second connection. In other embodiments, configuring the transmission includes controlling the transmission based on at least one parameter selected from the following group of parameters: an activation period assigned to the uplink transmission and a downlink transmission. The identification of one of the activation periods assigned to, the power level to be used for transmission, and the signal type to be used for transmission. Setting up transmission includes synchronizing a time base of the second connection to a frame time base of the first connection at the wireless device.

Further in accordance with an embodiment of the present invention, a wireless device having a radio frequency (RF) front end and a baseband circuit is provided. The radio frequency (RF) front end is configured to exchange RF signals for communication over a wide area wireless data network and over a wireless LAN (WLAN). The baseband circuit establishes a first connection with a base station (BS) on the wide area wireless data network via a radio frequency (RF) front end, and on the wireless LAN (WLAN) simultaneously with the first connection. In a mode in which two connections are established and the pattern of activation and deactivation periods is preset, between the first connection and the second connection, communicating with the base station (BS) on the first connection Is set to set transmission on the second connection based on a pattern of activation and deactivation periods preset for the first connection.
The invention will be more fully understood from the following detailed description of the embodiments with the accompanying figures:

1 is a block diagram schematically illustrating an LTE / Wi-Fi communication system according to an embodiment of the present invention. FIG. 2 is a flowchart schematically illustrating an LTE / Wi-Fi coexistence method according to an embodiment of the present invention. FIG. 6 is a diagram illustrating LTE / Wi-Fi transmission timing according to an embodiment of the present invention. FIG. FIG. 6 is a diagram illustrating LTE / Wi-Fi transmission timing according to an embodiment of the present invention. FIG. FIG. 3 is a block diagram schematically illustrating an LTE / Wi-Fi communication system according to another embodiment of the present invention. FIG. 6 is a diagram illustrating LTE / Wi-Fi transmission timing according to an embodiment of the present invention. FIG. 6 is a flowchart schematically illustrating an LTE / Wi-Fi coexistence method according to still another embodiment of the present invention.

(Introduction)
Some communication devices simultaneously communicate over a wide area data network (eg, Long Term Evolution (LTE) network) and over a wireless LAN (WLAN). In practice, transmissions on one network interfere with reception on other networks, especially when the transmitter and receiver are collocated and the two networks operate in adjacent or overlapping frequency bands. give.

  The embodiments of the invention described below provide improved methods and systems of coexistence, which help to reduce or eradicate such interference. Although the embodiments described herein are primarily described for LTE and WLAN (also referred to as Wi-Fi), the disclosed techniques are equally applicable to other compatible network types.

  In certain disclosed embodiments, the wireless device communicates simultaneously with one LTE base station (BS) and WLAN station (STA) or access point (AP). In accordance with the LTE standard, the LTE base station (BS) schedules uplink transmissions from the wireless device in response to a buffer status report (BSR) message in which the wireless device reports the amount of data awaiting transmission. The wireless device uses the BSR mechanism to generate a time interval that is free of LTE uplink and thus usable for Wi-Fi communication without interference.

  In some embodiments, the wireless device selects a time interval to be used for Wi-Fi communication. In preparation for the selected time interval, the wireless device transmits a zero BSR to the LTE base station (BS), i.e., reports no waiting data to the LTE base station (BS). To ensure that there is no LTE upward link. Upon receiving a BSR = 0 message, the LTE base station (BS) does not schedule any uplink data transfer from the wireless device until a non-zero BSR is received. Thus, the wireless device uses the time interval following the BSR = 0 message for Wi-Fi communication without the risk of LTE interference.

  In another disclosed embodiment, the wireless device communicates with an LTE base station (BS) in a time division (TD) LTE mode in a sequence of alternating upper and lower link intervals. At the same time, the wireless device communicates with a Wi-Fi station (STA) located near the wireless device. Because of the proximity, out-of-band emissions that overlap the LTE band from the Wi-Fi transmitter of the Wi-Fi station (STA) can cause interference in LTE reception. In one embodiment, this interference is reduced by the wireless device transmitting a signal to a neighboring Wi-Fi station (STA) to prevent the Wi-Fi station (STA) from transmitting during the downlink time interval. To prevent.

  In other disclosed embodiments, the wireless device is configured to communicate in a sparse pattern of active periods (eg, LTE subframes) separated by LTE base stations (BS) with inactive periods. For example, the wireless device may be configured to operate in a semi-persistent scheduling (SPS) mode and / or a discontinuous reception (DRX) mode, both defined in the LTE standard. In some embodiments, the wireless device may adapt communications on the WLAN based on LTE active / inactive patterns to reduce interference.

(System description)
FIG. 1 is a block diagram schematically illustrating an LTE / Wi-Fi communication system 20 according to an embodiment of the present invention. System 20 includes a communication device 24 that communicates simultaneously over both a wide area data network and a WLAN.

  In this case, the wide area data network operates according to the Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard. LTE, also referred to as E-UTRA, is a 3GPP technical standard, eg TS 36.300, version 9.6, entitled “Technical Standards Group Radio Access Network; E-URA and E-URAN; General Description; Stage 2 (Release 9)”. 0.0, December 2010, which is referenced and incorporated herein. In the context of the patent application and claims of the present invention, “LTE standard” refers generically to any standard or standard that defines LTE communications, including variations and extensions of the standard. In other embodiments, the wide area data network may operate based on other compatible current or future protocol standards.

  The current case WLAN operates according to IEEE 802.11. For example, WLAN operation in the 2.4 GHz frequency band is IEEE standard 802.11-2007, titled “IEEE Standard for IT—Telecommunication and Intersystem Information Exchange—Local and Metropolitan Networks—Specific Requirements: Part 11: Wireless LAN “Media Access Control (MAC) and Physical Layer (PHY) Standard”, defined by June 12, 2007, which is hereby incorporated by reference. WLAN is also called Wi-Fi. In the context of the patent application and claims of the present invention, “WLAN” and “Wi-Fi” refer to the original IEEE 802.11 and all variations and extensions of the above standards (eg, IEEE 802.11n-2009). As well as any other suitable WLWLAN type.

  In the embodiment of FIG. 1, the communication device 24 communicates with an LTE base station (BS) 28, also referred to as eNodeB. Accordingly, the communication device 24 functions as an LTE user equipment (UE). On a Wi-Fi network, the communication device 24 functions as a Wi-Fi station (STA) in some embodiments, and functions as a Wi-Fi access point (AP) in other embodiments. Accordingly, the communication device 24 communicates with the Wi-Fi station (STA) or the Wi-Fi access point (AP) 32 over the WLAN. Communication device 24 may be implemented in a multi-mode communication device, such as a smartphone, mobile router, fixed router, or other suitable device.

  In various embodiments, LTE and Wi-Fi communication are communicated in adjacent frequency bands. In one case, the communication device 24 operates in band 7 according to LTE frequency division duplex (FDD), the upper link (UL) is transmitted in the 2500-2570 MHz range, and the lower link (DL) is transmitted in 2620-2690 MHz. And transmitted on the Wi-Fi network in the 2400-2480 MHz range. Alternatively, other operating modes (eg time division duplex communication TDD) and frequency bands can be used. Due to the close location and frequency, operations in one network may be subject to interference from other networks. As described in detail below, the communication device 24 applies a coexistence scheme that reduces or eliminates such interference. When these technologies are applied, the communication device 24 can simultaneously execute LTE and Wi-Fi communication sessions with little or no performance degradation for either network.

  Although the embodiments described herein primarily describe a single communication device with LTE and Wi-Fi capabilities, some of the techniques disclosed herein are isolated but proximate LTE with interference problems. It is equally applicable to Wi-Fi devices.

  In the embodiment of FIG. 1, the communication device 24 has an antenna 36 and a radio frequency (RF) front end 40, using which the communication device 24 is an LTE base station (BS) 28 and a Wi-Fi station (STA). Alternatively, an RF signal is exchanged with the Wi-Fi access point (AP) 32, and communication is performed on the LTE and Wi-Fi networks. The LTE baseband (BB) processor 44 performs the LTE user equipment (UE) processing function of the device. A Wi-Fi baseband (BB) processor 48 performs the Wi-Fi (STA or AP) processing function of the device.

  In one embodiment, LTE and Wi-Fi baseband (BB) processors communicate with each other over a coexistence interface to exchange information that contributes to LTE / Wi-Fi coexistence. The RF front end 40 is shared by LTE and Wi-Fi, i.e. performs transmission and reception for both LTE and Wi-Fi networks. The RF front end 40 may have a suitable filter that mitigates or reduces LTE / Wi-Fi interference.

  The configuration of the communication device 24 shown in FIG. 1 is an exemplary configuration and was selected only for the purpose of clarifying the concept. In other embodiments, other suitable device configurations can be used. For example, LTE and Wi-Fi communication may be performed via a separate RF front end and antenna. As another example, LTE baseband (BB) processor 44 and Wi-Fi baseband (BB) processor 48 may be implemented by a single baseband (BB) processor. In this description, LTE baseband (BB) processor 44 and Wi-Fi baseband (BB) processor 48 are collectively referred to as baseband circuits that implement the disclosed techniques. Certain elements of communication device 24 may be implemented using hardware such as one or more application specific ICs (ASICs) or field programmable gate arrays (FPGAs). Alternatively, certain elements of the communication device 24 may be implemented using software or a combination of hardware and software elements.

  In certain embodiments, the functions of communication device 24 may be performed using a general purpose computer programmed in software to perform the functions described herein. The software may be downloaded to the computer in electronic form, for example over a network, or additionally provided and / or stored on a non-transitory accessible medium such as magnetic, optical, electronic memory.

(Coexistence using buffer status report (BSR))
In an embodiment, the communication device 24 generates a time interval without LTE uplink (from the communication device 24 to the LTE base station (BS) 28) using a buffer status report (BSR) defined in LTE. . These time intervals can then be used for Wi-Fi communication without the risk of LTE transmission from the communication device 24 affecting the device's Wi-Fi reception.

  The Buffer Status Reporting (BSR) mechanism is defined in section 11.3 of 3GPP TS 36.300 cited above, but also has the title “Technical Standards Group Radio Access Network; E-URA; MAC Protocol Standard (Release 9) 3GPP Technical Standard, TS 36.300, Version 9.3.0, June 2010, also defined in section 5.4.5 of 3GPP TS 36.321, which is hereby incorporated by reference. . In accordance with this definition, the LTE user equipment (UE) uses a buffer status report (BSR) message to report to the LTE base station (BS) the amount of data buffered in its transmission buffer and awaiting transmission. A zero BSR means there is no data waiting. The LTE base station (BS) schedules uplink transmissions for various UEs based on the BSR messages they transmit. In particular, if a particular UE reports BSR = 0, the LTE base station (BS) will not schedule uplink data transmissions for that UE until it subsequently receives a non-zero BSR.

  In one embodiment, the LTE baseband (BB) processor 44 of the communication device 24 selects a time interval for communication over the Wi-Fi network. In preparation for the selected time interval, the LTE baseband (BB) processor 44 sends a BSR = 0 message (indicating that there is no data waiting to be sent to the BS) to the LTE base station (BS) 28 before that interval. To ensure that there are no LTE uplink transmissions in that time interval. The LTE baseband (BB) processor 44 sends a non-zero BSR message (indicating that there is a certain amount of data waiting to be sent to the BS) towards the end of the interval. In response to receiving the BSR = 0 message, the LTE base station (BS) 28 refrains from scheduling LTE uplink transmissions from the communication device 24. The LTE base station (BS) 28 schedules the LTE uplink transmission after receiving the non-zero BSR message.

  In this way, the LTE baseband (BB) processor 44 allows the system 20 to operate between a time interval intended for LTE uplink transmission and a time interval without LTE uplink transmission (and thus usable for Wi-Fi communication). You may make it operate | move by the pattern which repeats alternately.

  FIG. 2 is a flowchart schematically illustrating an LTE / Wi-Fi coexistence method according to an embodiment of the present invention. The method begins with a non-zero BSR step 60 where the LTE baseband (BB) processor 44 sends a buffer status report (BSR) message reporting non-zero BSR to the LTE base station (BS) 28.

  In one embodiment, in Wi-Fi block step 64, the communication device 24 blocks Wi-Fi communication during the time interval used for LTE uplink transmission. For example, the LTE baseband (BB) processor 44 transmits an appropriate instruction via the coexistence interface, so that the Wi-Fi baseband (BB) processor 48 prohibits Wi-Fi communication.

  Upon receiving a non-zero BSR, the LTE baseband (BB) processor 44 schedules uplink transmissions from the communication device 24. In an LTE uplink transmission step 68, the LTE baseband (BB) processor 44 uses this assignment to transmit waiting data to the LTE base station (BS) 28 during that time interval.

  At the end of the LTE uplink interval, in a zero BSR step 72, the LTE baseband (BB) processor 44 tells the LTE base station (BS) 28 that the BSR is zero (ie, there is no waiting data in the transmit buffer). ) Send a message to report that. In response to the zero BSR message, the LTE base station (BS) 28 does not schedule LTE uplink transmissions from the communication device 24. Thus, in the Wi-Fi communication step 76, the Wi-Fi baseband (BB) processor 48 does not have the risk of interference from LTE uplink transmissions, on the Wi-Fi network, on a Wi-Fi station (STA) or Wi-Fi. -Communicate with Fi access point (AP) 32.

  The method then loops back to step 60 for scheduling another LTE LTE uplink interval. Using this technique, the communication device 24 may force an alternating pattern of LTE upper link intervals and intervals without LTE uplink transmission.

  When using this method, in at least some scenarios, the communication device 24 may report a zero BSR even though there is waiting data in its transmit buffer. This type of report causes the LTE base station (BS) 28 to schedule transmission of this data on the LTE uplink only after subsequent reception of non-zero BSR. In other words, this technique allows the communication device 24 to stretch the transmission of the uplink data until the end of the time interval.

  There is usually a certain delay between the transmission of non-zero BSR messages from the communication device 24 and the scheduling of uplink transmissions by the LTE base station (BS) 28. This delay is due to the LTE protocol, and its magnitude is about 10 ms. The normal LTE baseband (BB) processor 44 takes this delay (latency) into account when setting the timing of the time interval. In some embodiments, the LTE baseband (BB) processor 44 sets the time interval size and / or duty cycle while taking into account the actual throughput of the LTE connection from the communication device 24 to the LTE base station (BS) 28. To do. These parameters can be set, for example, by setting a reported BSR value (a reported value of waiting data).

  For example, assume that the average uplink throughput is 10 Mbps (= 10 Kbps / ms), and the desired activation time (the length of each uplink link interval) is 10 ms. In such a case, sending a BSR message reporting that there is 100 Kb of waiting data causes the LTE base station (BS) 28 to schedule an uplink transmission of about 10 ms. Thus, in at least some cases, the amount of data that communication device 24 reports in a non-zero BSR message is different from the actual amount of data waiting to be transmitted.

  FIG. 3 is a diagram illustrating LTE and Wi-Fi transmission timing according to one embodiment of the present invention. The example of FIG. 3 shows how the communication device 24 uses the BSR mechanism described above to generate a time interval for LTE uplink and a time interval without LTE uplink transmission.

  The upper part of FIG. 3 shows LTE control messaging, in particular a non-zero BSR message 80 and a zero BSR message 88 sent from the communication device 24 to the LTE base station (BS) 28. The middle part of FIG. 3 shows the timing of LTE uplink data transmission. The LTE base station (BS) 28 schedules the LTE uplink transmission 84 with a certain delay (latency, eg 10 ms) after each non-zero BSR. The lower part of FIG. 3 shows the time period of Wi-Fi activity. In particular, Wi-Fi activity is blocked during the Wi-Fi block interval 92 (corresponding to LTE uplink transmission 84) to avoid interference from LTE uplink transmissions.

  The communication device 24 sends a zero BSR message 88 to the LTE base station (BS) 28 towards the end of the LTE uplink transmission. After the zero BSR message, the LTE base station (BS) does not schedule LTE uplink transmission until the next non-zero BSR message 80. These BSR messages thus form a Wi-Fi active period 96 in which the communication device 24 can communicate over the Wi-Fi network without interference from the LTE uplink.

  In one case, each uplink data transmission 84 is 20 ms long and each Wi-Fi active period 96 is 15 ms long. Alternatively, any other suitable length can be used.

  The LTE baseband (BB) processor 44 blocks Wi-Fi communication in various ways during the Wi-Fi block interval 92. In one embodiment, the LTE baseband (BB) processor 44 explicitly tells the Wi-Fi baseband (BB) processor 48 about the timing of the Wi-Fi block interval 92 using a coexistence interface between BB processors. Give information. The Wi-Fi baseband (BB) processor 48 can transmit during any Wi-Fi block interval 92 in any suitable manner, eg 'transmit to itself (CTS-to-self) ending at the end of the LTE uplink transmission interval 84. ) ′ May be used to prohibit Wi-Fi communication by setting a disabled (NAV) interval.

  In other embodiments (eg, when LTE and Wi-Fi baseband (BB) processors are in separate devices and / or not connected by coexistence interfaces), LTE baseband (BB) processor 44 is Information about the timing of the Wi-Fi block interval 92 is not given to the Wi-Fi baseband (BB) processor 48. In these embodiments, Wi-Fi downlink reception during Wi-Fi block interval 92 is subject to interference from LTE uplink transmissions. The level of interference can be, for example, RF front end filter quality, isolation between LTE and Wi-Fi antennas in communication device 24, LTE transmitter transmit power and other RF parameters, Wi-Fi receiver RF parameters, And depends on Wi-Fi modem quality. In case of severe interference, the Wi-Fi packet is dropped and retransmitted until it is successfully received (either in the Wi-Fi block interval 92 or in the subsequent interval 84 without interference).

  The coexistence technique based on the buffer status report (BSR) can be implemented in the communication device 24 by various methods. In some embodiments, a BSR coexistence scheme is performed by the LTE baseband (BB) processor 44. This implementation is advantageous because the LTE baseband (BB) processor 44 running the LTE protocol stack already has the necessary information regarding the transmit buffer status. Further, the LTE baseband (BB) processor 44 may have valuable information regarding LTE base station (BS) behavior, for example, LTE base station (BS) delay when responding to non-zero BSR. Good. This kind of information can be used to optimize the coexistence scheme.

  In other embodiments, buffer status reporting (BSR) based coexistence techniques may be performed by other processors external to the LTE baseband (BB) processor 44. In one case, the coexistence scheme may be performed by a Wi-Fi baseband (BB) processor 48 in the case of a Wi-Fi access point (AP). In these embodiments, the control of the BSR is indirect and by other processors controlling the information rate provided to the LTE baseband (BB) processor 44. In this embodiment, typically other processors should receive explicit information about the average LTE uplink throughput, or should implicitly calculate this throughput by examining the output packets. Such an implementation may be advantageous because, for example, there is no need to change the current LTE baseband (BB) processor or other LTE user equipment (UE) elements.

  Regardless of the implementation, the size of the LTE transmit buffer of the communication device 24 must be large enough to hold the uplink packet and support the LTE uplink inactive duration.

  The above buffer status report (BSR) based scheme assumes that the main interference source of the communication device 24 is for Wi-Fi downlink reception from LTE uplink transmissions. When the interference in the opposite direction, i.e., interference with reception of the Wi-Fi uplink to the LTE downlink transmission, is tolerated or otherwise mitigated (e.g., using sufficient filtering at the RF front end 40) It is assumed.

  In some embodiments, following a zero BSR message, LTE base station (BS) 28 does not schedule data transmissions on the LTE uplink, but may schedule control related uplink transmissions. These control-related transmissions are unlikely to cause interference to the Wi-Fi downlink because their output power is generally less than the output power of the data transmission. In some embodiments, it may be possible to cease control-related transmissions from time to time depending on the expected level of interference.

(BSR-based coexistence for time division LTE user equipment (UE) co-located with Wi-Fi access point)
FIG. 4 is a diagram illustrating the timing of LTE and Wi-Fi transmission according to one embodiment of the present invention. In this embodiment, LTE communication of the LTE baseband (BB) processor 44 follows LTE time division (TD), and the Wi-Fi baseband (BB) processor 48 functions as a Wi-Fi access point (AP). In this case, each LTE time division (TD) downlink link frame and LTE time division (TD) uplink frame is 2.5 ms in length, but any other suitable frame size can be used.

  During the Wi-Fi block interval 92, the Wi-Fi baseband (BB) processor 48 inhibits Wi-Fi communication as described above. During these intervals (corresponding to the LTE upper link transmission interval 84), LTE communication can be performed on both the upper and lower links.

  During the period between Wi-Fi block intervals 92 (ie during the Wi-Fi active period), the LTE uplink transmission 108 does not interfere with Wi-Fi reception due to the above BSR-based mechanism. . However, interference can occur during LTE downlink transmission 112. (In a frequency division duplex (FDD) scenario, it is assumed that FDD band 7 is used, where the LTE downlink frequency is relatively far from the Wi-Fi frequency and the front end isolation is Wi- It is assumed to be sufficient to prevent interference in the Fi active period interval 96).

  In this embodiment, the Wi-Fi access point (AP) is collocated with the LTE user equipment (UE), so this interference can be reduced. In one embodiment, the Wi-Fi access point (AP) (in this example, the baseband (BB) processor 48) is aware of and is synchronized with time division (TD) LTE frame timing. Wi-Fi access point (AP) transmission 100 is synchronized to LTE uplink link interval 108. For this reason, the Wi-Fi access point (AP) (baseband (BB) processor 48) usually knows the start time and duration of the LTE uplink link interval 108 and adapts the Wi-Fi data dimensions to these intervals. (Eg, by fragmenting the packet).

  Further, in some embodiments, the end of each Wi-Fi access point (AP) transmission 100 is aligned with the end of one LTE uplink link 108. Due to the alignment, each Wi-Fi acknowledgment (ACK) 104 (sent from the Wi-Fi station (STA) 32 to the Wi-Fi access point (AP) of the wireless device 24) is received during the LTE downlink interval 112. The

  The Wi-Fi receiver of communication device 24 may be allowed to operate during LTE downlink link interval 112. When the Wi-Fi burst 116 is received, the Wi-Fi access point (AP) of the communication device 24 should transmit an acknowledgment (ACK) burst 120. The transmitted ACK burst may interfere with reception of the LTE downlink. In some embodiments, the Wi-Fi access point (AP) (baseband (BB) processor 48) of the communication device 24 may receive an acknowledgment (ACK) burst 120 at low output power and possibly low (more powerful). This problem is overcome by transmitting with a modulation and coding scheme (MCS).

  Alternatively, the LTE baseband (BB) processor 44 may mitigate interference due to an acknowledgment (ACK) burst 120 as part of LTE downlink reception. Such mitigation is possible, for example, because the acknowledgment (ACK) waveform and associated parameters are known to the communication device 24 and the duration of the acknowledgment (ACK) burst 120 is relatively short. The LTE receiver of this embodiment has been previously informed about the parameters of the acknowledgment (ACK) waveform and cancels this known interference in its demodulation / decoding process.

  In other embodiments, the LTE time division (TD) frame pattern has a finite gap between the upper link interval 108 and the lower link interval 112. These gaps can be used to transmit a Wi-Fi acknowledgment (ACK) message from the Wi-Fi access point (AP) of the communication device 24 without causing interference.

(Coexistence of juxtaposed time division (TD) LTE user equipment (UE), Wi-Fi access point (AP), and neighboring Wi-Fi station (STA))
FIG. 5 is a block diagram schematically illustrating an LTE / Wi-Fi communication system 130 according to another embodiment of the present invention. In system 130, a communication device 134 may use time division (TD) LTE and an LTE base station (BS) (eNodeB) 138, and Wi-Fi using one or more Wi-Fi stations (STAs). Communicate simultaneously. In this case, the communication device 134 communicates with a remote Wi-Fi station (STA) 142 and a nearby Wi-Fi station (STA) 146.

  The communication device 134 may be realized by, for example, a portable router or a smartphone having LTE and Wi-Fi access point (AP) functions. Although the embodiments described herein describe LTE and Wi-Fi, the disclosed techniques are equally applicable to other wide area data networks or WLANs as described with respect to FIG. is there.

  Similar to the communication device 24 of FIG. 1, the communication device 134 includes an antenna 35 and an RF front end 40. The communication device 134 also includes an LTE baseband (BB) processor 150 that functions as a time division (TD) LTE user equipment (UE), and a Wi-Fi baseband (BB) that functions as a Wi-Fi access point (AP). A processor 154; In one embodiment, these baseband (BB) processors 150 and 154 communicate with each other over a coexistence interface.

  In this embodiment, the Wi-Fi station (STA) 146 is located in close proximity to the communication device 134, for example, a distance of less than 1 meter. In this description, “very near” means a distance at which the LTE receiver of the communication device 134 receives interference from the Wi-Fi transmitter of the Wi-Fi station (STA) 146 even if there is no frequency overlap between them. Means. For example, the Wi-Fi station (STA) 146 may emit out-of-band spurious signals or noise that overlap the LTE band and may interfere in the immediate vicinity.

  The Wi-Fi station (STA) 146 may comprise, for example, a netbook, smartphone, tablet computer, laptop computer, or other suitable type of Wi-Fi station (STA). Since the Wi-Fi station (STA) 146 is located in the immediate vicinity of the communication device 134, it interferes with not only the Wi-Fi reception of the neighboring Wi-Fi station (STA) 146 but also the Wi-Fi and LTE reception of the communication device 134. Occurs. The following description provides an example coexistence scheme that mitigates this interference.

  The disclosed technique is between baseband (BB) processors 150 and 154 (ie, juxtaposed within communications device 134) to reduce interference to and from neighboring Wi-Fi stations (STAs) 146. It focuses on protocol level coordination between time division (TD) LTE user equipment (UE) and Wi-Fi access point (AP). As a premise, it is assumed that the Wi-Fi station (STA) 146 is not necessarily designed for coexistence, for example, with respect to receiver linearity and transmitter transmission. It is assumed that a time division (TD) LTE user equipment (UE) and a Wi-Fi access point (AP) co-located within the communication device 134 coexist, for example by using sufficient filtering in the RF front end 40. Yes. This filtering may include interference to Wi-Fi baseband (BB) processor 154 Wi-Fi reception from LTE baseband (BB) processor 150 LTE transmissions, and Wi-Fi baseband (BB) processor 154 Wi-Fi. It is assumed that the LTE baseband (BB) processor 150 from the transmission overcomes interference to LTE reception.

In such a configuration, several different interference modes can occur, as summarized in the following table:

As can be seen from the table, the main form of interference is interference with LTE reception of the communication device 134 from the neighboring Wi-Fi station (STA) 146.
Because the distance between the neighboring Wi-Fi station (STA) 146 and the Wi-Fi access point (AP) of the communication device 134 is short, the neighboring Wi-Fi station (STA) 146 has a high modulation and coding scheme on the Wi-Fi channel. (MCS) can be transmitted, so the burst duration of Wi-Fi transmission is relatively short. In some embodiments, this feature allows Wi-Fi bursts transmitted by neighboring Wi-Fi stations (STAs) 146 to fit within (relatively short) LTE upper and lower intervals (typically about 2.5 ms).

  FIG. 6 is a diagram illustrating the timing of LTE and Wi-Fi transmissions according to one embodiment of the invention. This figure shows an exemplary coexistence scheme, in which communication device 134 uses the scheme for LTE reception of LTE baseband (BB) processor 150 from a Wi-Fi transmission of a neighboring Wi-Fi station (STA) 146. Reduce interference.

  The upper part of FIG. 6 shows a frame pattern of a time division (TD) LTE user equipment (UE) (baseband (BB) processor 150), and the middle part of the figure shows a Wi-Fi access point (AP) (baseband) of the communication device 134. (BB) shows the operation of the processor 154), and the lower part shows the operation of the neighboring Wi-Fi station (STA) 146.

  The LTE user equipment (UE) baseband (BB) processor 150 operates in a pattern in which the lower link interval 160 and the upper link interval 164 alternate. An upper link guard interval 168 is inserted between each lower link interval 160 and the subsequent upper link interval 164. In one embodiment, the lower link interval 160 and the upper link interval 164 are the same size, i.e. the ratio of the lower link and the upper link time is 50% / 50%. In this embodiment, each lower link and upper link interval is approximately 2.2 ms, and the upper link guard interval 168 is approximately 0.6 ms. Alternatively, other suitable numbers can be used.

  In one embodiment, the collocated Wi-Fi access point (AP) (baseband (BB) processor 154) uses the Wi-Fi time base as an LTE frame for LTE user equipment (UE) (baseband (BB) processor 150). Synchronize to the time base. As described below, the Wi-Fi AP (BB processor 154) schedules its Wi-Fi operation based on the LTE frame configuration. During the downlink interval 160, the Wi-Fi AP (BB processor 154) transmits a signal to the neighboring Wi-Fi station (STA) 146 to prevent interference to LTE reception of the LTE UE (BB processor 150). May transmit to the Fi station (STA) 146 and block traffic of the neighboring Wi-Fi station (STA) 146 at least until the beginning of the next uplink guard interval 168 (eg, transmit to itself (CTS-to -Self) using a message or other suitable technique).

  A block interval 172 in which a nearby Wi-Fi station (STA) 146 is blocked from transmitting is shown in the middle of the figure. As can be seen, the neighboring Wi-Fi station (STA) 146 does not transmit during the LTE downlink link interval 160 (i.e. during LTE reception of the LTE UE (BB processor 150)). Thus, the main source of interference in system 130 disappears.

  Due to this blocking, in most scenarios, the neighboring Wi-Fi station (STA) 146 starts a transmission burst 192 during the upper link guard interval. This is because the neighboring Wi-Fi station (STA) 146 is blocked from transmitting until this point. The transmission burst 192 may end either before or after the beginning of the next LTE uplink link 164. In any case, the transmission burst 192 is successfully received by the Wi-Fi AP (BB processor 154). Reception of the transmission burst 192 is indicated by an interval 176 in the figure.

    In most cases, the transmission burst 192 is based on the current LTE uplink interval given the high modulation and coding scheme (MCS) that is enabled by the proximity of the neighboring Wi-Fi station (STA) 146 and the communication device 134. End before 164. As described above, because the neighboring Wi-Fi station (STA) 146 is in close proximity to the communication device 134, communication between the neighboring Wi-Fi station (STA) 146 and the communication device 134 has a high modulation and coding scheme ( MCS), which shortens the communication burst and allows the communication burst to fit outside of the LTE downlink link 160.

  As soon as burst 192 is received, the Wi-Fi access point (AP) (baseband (BB) processor 154) should respond with an acknowledgment (ACK) 180. Acknowledgments (ACKs) may be transmitted at a low bit rate because neighboring Wi-Fi stations (STAs) 146 are slightly reduced in interference or sensitivity by LTE uplink transmission within the uplink interval 164. Because. Reception of acknowledgment (ACK) 180 at the neighboring Wi-Fi station (STA) 146 is indicated by an interval 196. Normally, the neighboring Wi-Fi station (STA) 146 does not start sending a new burst during the same LTE uplink link interval 164. This is because its Clear Channel Assessment (CCA) mechanism can be blocked as a result of LTE transmission. The CCA block period is indicated by interval 200.

  In one embodiment, an expected acknowledgment (ACK) from a Wi-Fi station (STA) 146 (denoted as interval 208 and received as an interval 188 at the Wi-Fi AP (BB processor 154)) is LTE. As long as transmissions are scheduled as calculated during reception in the upper link interval 164 (current LTE upper link interval 164 or subsequent LTE upper link interval 164), the Wi-Fi AP ( The BB processor 154) may schedule its transmission 184 to begin during the LTE upper link interval 164 or during the subsequent LTE lower link interval 160.

  In an embodiment, if the transmission occurs during the LTE uplink link 164, the neighboring Wi-Fi station (STA) 146 is highly modulated in combination with high interference from the LTE uplink transmission of the LTE UE (BB processor 150). And the Wi-Fi AP (BB processor 154) reduces the modulation and coding scheme (MCS) of the transmission 184 to take into account the case where the coding scheme (MCS) cannot be handled.

  In one embodiment, the Wi-Fi AP (BB processor 154) extends the duration of a given transmission 184 beyond the LTE lower link interval 160, and the acknowledgment (ACK) 208 is received during an LTE upper link interval 164. Received. The Wi-Fi AP (BB processor 154) adds the duration of the transmission 184, eg, by deliberately reducing the modulation and coding scheme (MCS) used for the transmission, or adding dummy information bytes to the transmission. Or by concatenating multiple packets to form a single long transmission 184, or using any other suitable technique.

  In some embodiments, towards the end of the LTE uplink interval 164, the Wi-Fi AP (BB processor 154) initiates a new transmission 184 or moves the subsequent LTE downlink link 160 to the Wi-Fi station ( STA) block from sending (using a CTS-to-self process or other suitable technology). This block (interval 172) should end at or after the start of the next upper link guard interval 168. The Wi-Fi AP (BB processor 154) may schedule the transmission burst 184 immediately after the end of the block interval 172, and the transmission burst 184 itself is either at the end of the lower link interval 160 or during the upper link guard interval 168. Either ends in In such a case, a corresponding acknowledgment (ACK) 208 is received during the upper link guard interval 168 or during the subsequent upper link interval 164.

  In an embodiment, the Wi-Fi AP (BB processor 154) of the communication device 134 blocks or defers transmission to a neighboring Wi-Fi station (STA) 146, and the neighboring Wi-Fi station (STA) 146 An acknowledgment (ACK) message for transmission is not transmitted during the downlink link interval of the LTE connection. This technique prevents interference with LTE reception of the LTE UE (BB processor 150) due to the acknowledgment (ACK) transmitted from the neighboring Wi-Fi station (STA) 146.

  In some embodiments, the Wi-Fi AP (BB processor 154) is not in the vicinity (and thus does not interfere with LTE user equipment (UE) reception) additional Wi-Fi stations (STAs) (eg, Wi-Fi station 142). Communicate with. For example, the Wi-Fi AP (BB processor 154) may schedule communication with other Wi-Fi stations (STAs) at any time (eg, during the LTE upper link interval 164 or during the LTE lower link interval 160). . If the Wi-Fi channel is blocked (during an interval 172 that prevents transmission of a neighboring Wi-Fi station (STA) 146), the Wi-Fi AP (BB processor 154) may cause the neighboring Wi-Fi station (STA) to Blocks only 146, but transmits a block transmission (eg, transmission to itself (CTS-to-self)) at low power so that it can communicate with other Wi-Fi stations (STAs). May be.

  In an embodiment, if the LTE downlink signal is received at a level above a certain threshold at the LTE UE (BB processor 150), the Wi-Fi AP (BB processor 154) may be Wi- during the LTE downlink link interval 160. You may refrain from blocking the Fi station (STA).

  In some cases, the LTE uplink transmission signal (at interval 164) is below a certain threshold and the neighboring Wi-Fi station (STA) 146 clear channel assessment (CCA) mechanism is not activated. In one embodiment, the Wi-Fi AP (BB processor 154) may send an explicit Wi-Fi transmission (or block) to prevent neighboring Wi-Fi stations (STAs) 146 from initiating new transmission bursts 192. ) May be used to protect the LTE lower link interval 160. In these embodiments, the block operation should have priority over attempts by neighboring Wi-Fi stations (STA) 146 to transmit another burst 192. This priority is achieved, for example, by changing the Wi-Fi access point (AP) random backoff process (via Wi-Fi carrier sense multiple access (CSMA) media access control (MAC) protocol). Is possible.

  In one embodiment, the block scheme of FIG. 6 can be combined with the BSR-based scheme of FIGS. 2-4 to generate a known (often long) period without LTE uplink data transmission. is there.

  In some embodiments, the LTE UE (BB processor 150) may be required to perform measurements that periodically monitor neighboring LTE base stations (eNodeBs). In these embodiments, the LTE UE (BB processor 150) notifies the co-located Wi-Fi AP (BB processor 154) of the measurement interval, and the Wi-Fi AP (BB processor 154) communicates with a neighboring Wi-Fi station. (STA) 146 may be blocked from transmitting during these intervals. This additional protection mechanism may be applied in the case of a sensitive LTE period, such as a handover period or a known period used for transmission of system control information.

(Coexistence between juxtaposed WI-FI devices and LTE devices operating in SPS / DRX mode)
The LTE standard defines two modes in which LTE user equipment (UE) operates in a pattern with sparse active periods to schedule overhead and / or conserve battery power-semi-persistent scheduling (SPS) And discontinuous reception (DRX). SPS and DRX are defined in Section 5 of 3GPP TS 36.321 above. In both modes (they apply separately or together for the same LTE user equipment (UE)), the LTE user equipment (UE) is pre-configured with a pattern in which active periods are separated by inactive periods. The

  The pattern is synchronized between the LTE user equipment (UE) and the LTE base station (BS), and the LTE user equipment (UE) can predict in advance in which LTE subframe a non-uplink or downlink will occur . Thus, the LTE user equipment (UE) can wake up and communicate with the BS when necessary in the active period, while remaining in sleep mode during the inactive period. For example, the pattern may define an active period of 1 ms every 20 ms, an active period of 5 ms every 15 ms, or other suitable pattern.

  Consider the system configuration of FIG. In certain embodiments, an LTE baseband (BB) processor 44 functioning as an LTE user equipment (UE) operates in an LTE base station (BS) to operate in semi-persistent scheduling (SPS) and / or discontinuous reception (DRX) mode. ) 28. As part of this configuration, the LTE base station (BS) configures the LTE baseband (BB) processor 44 with a desired active and inactive period pattern. The LTE baseband (BB) processor 44 transmits the pattern to the Wi-Fi baseband (BB) processor 48 (acting as a WLAN station (STA) or access point (AP)), possibly with additional information, on the coexistence interface. provide. The Wi-Fi baseband (BB) processor 48 uses that information to set up Wi-Fi operation, reducing mutual interference.

  In various embodiments, the Wi-Fi BB processor 48 may set up its own Wi-Fi transmission and / or transmission of the opposing Wi-Fi endpoint (station (STA) or access point (AP) 32). . Station (STA) or access point (AP) settings may include Wi-Fi transmission and / or receiver functionality settings. This setting is for interference of LTE BB processor 44 LTE reception from Wi-Fi BB processor 48 Wi-Fi transmission and / or Wi-Fi BB processor 48 Wi-Fi reception from LTE BB processor 44 LTE transmission. Can be used for reduction. To facilitate this operation, the LTE BB processor 44 typically provides LTE frame timing to the LTE BB processor 44 via the coexistence interface. The Wi-Fi BB processor 48 synchronizes its internal time base with the LTE frame timing provided by the LTE BB processor 44.

  Typically, the LTE BB processor 44 provides patterns and related information to the Wi-Fi BB processor 48 in advance to allow the Wi-Fi BB processor 48 sufficient time to set up Wi-Fi operation. The information provided is, for example, which subframes are defined as active, which subframes are defined as inactive, which active subframes are used for LTE user equipment (UE) transmission (uplink), which Active subframes are used for LTE user equipment (UE) reception (downlink), including transmission and reception signal power levels, type of signal transmitted or received, and / or any other suitable information .

  In the exemplary embodiment, the Wi-Fi BB processor 48 sets the timing of Wi-Fi transmission based on the pattern of LTE active and inactive periods. Timing is set either or both locally for the Wi-Fi BB processor 48 transmission or remotely for the opposite station (STA) or access point (AP) 32 transmission ( (E.g., using a CTS-to-self process).

  In some embodiments, the Wi-Fi BB processor 48 may suspend all Wi-Fi transmissions during the active LTE period. In other embodiments, the Wi-Fi BB processor 48 may suspend Wi-Fi transmissions at a finer granularity, eg, during the active period used for reception of the LTE BB processor 44, from the communication device 24. Only Wi-Fi transmission may be suspended.

  In one embodiment, the LTE BB processor 44 is required to perform measurements that periodically monitor surrounding base stations (BS, eNodeBs). In these embodiments, the LTE user equipment (UE) informs the co-located Wi-Fi BB processor 48 of the measurement interval, and the Wi-Fi BB processor 48 reduces interference during the reported interval.

  In certain embodiments, the pattern of active / inactive periods is adapted according to various system parameters of LTE and / or Wi-Fi channels, eg, current transmit power, currently used modulation and coding scheme (MCS). The received power of the opposite transmission, the amount of traffic transmitted, and / or any other suitable system parameters.

  FIG. 7 is a flowchart schematically illustrating an LTE / Wi-Fi coexistence method according to still another embodiment of the present invention. In configuration step 210, the method configures LTE base station (BS) 28 to configure LTE user equipment (UE) (BB processor 44) of communication device 24 according to SPS and / or RDX mode in a pattern of active and inactive time periods. Start with steps.

  The Wi-Fi BB processor 48 synchronizes its internal time base with the LTE BB processor 44 LTE frame timing in a synchronization step 214. The LTE BB processor 44 provides the pattern of active and inactive time periods to the Wi-Fi BB processor 48 in the pattern announcement step 218. In the Wi-Fi adaptation step 222, the Wi-Fi BB processor 48 determines the Wi-Fi operation (its own local operation and / or the operation of the opposing Wi-Fi station (STA) or access point (AP)) in the pattern. Adapt based on. Adaptation attempts to reduce or eradicate interference between LTE and Wi-Fi connections.

  The configurations of communication devices 24 and 134 of FIGS. 1 and 5 are exemplary configurations and were selected purely for conceptual clarity. In other embodiments, any other suitable configuration can be used. For example, LTE and Wi-Fi communication can be performed via different antennas. As another example, the functions of baseband (BB) processors 44 and 48 or baseband (BB) processors 150 and 154 can be performed by a single baseband (BB) processor. In the current context, the baseband (BB) processors 44 and 48 of FIG. 1 and the baseband (BB) processors 150 and 154 of FIG. 5 are collectively referred to as baseband circuits that implement the disclosed techniques. Certain elements of the communication devices 24 and 134 can be implemented using one or more hardware such as ASICs or FPGAs. Alternatively, some elements of the communication device 24 or 134 can be implemented in software or using a combination of hardware and software.

  In certain embodiments, the functions of the communication device 24 or 134 can be performed using a general purpose computer programmed with software to perform the functions described herein. The software may be downloaded, for example, in electronic form to a computer, over a network, or alternatively provided and / or stored on a non-transitory contactable medium such as magnetic, optical or electronic memory. Good.

The above embodiments are cited as examples, and the invention is not limited to what has been particularly shown and described herein. Rather, the scope of the present invention includes combinations and subcombinations of the various features described above, as well as variations and modifications not found in the prior art that will occur to those skilled in the art upon reading the above description. Documents incorporated by reference into this application should be considered an integral part of this application. However, if any term defined in the adopted document is explicitly or implicitly different from the definition of the present specification, the definition of the present specification takes precedence.

Claims (14)

A communication method,
Establishing, in a wireless device, a first connection with a base station (BS) of a wide area wireless data network and establishing a second connection over a wireless LAN (WLAN);
Selecting a time interval for communicating on the second connection in the wireless device;
In preparation for the selected time interval, prior to the time interval, by reporting to the base station (BS) that there is no data waiting for transmission from the wireless device, to the base station (BS), Refraining from scheduling data transmissions from the wireless device to the base station (BS) on the first connection during the time interval; and
Communicating over the second connection of the wireless LAN (WLAN) using the wireless device during the time interval;
I have a,
It said step of reporting the data is not waiting for transmission, in order to schedule the transmission of the transmission waiting data outside of the time interval to the base station (BS), several data are the base station (BS) A method characterized in that it is executed even when waiting for transmission.   The method of claim 1, comprising reporting to the base station (BS) that there is data waiting to be transmitted from the wireless device in preparation for the end of the time interval. The step of reporting that there is data waiting to be transmitted includes the step of reporting a data amount different from the actual size of the data waiting to be transmitted in order to control the size of the scheduled transmission. Item 3. The method according to Item 2 . The wide area wireless data network operates in accordance with a Long Term Evolution (LTE) standard, and the step of reporting that there is no data waiting to be transmitted includes the step of transmitting a buffer status report (BSR) message. Item 4. The method according to any one of Items 1-3 . The first connection and the second connection are alternately performed by alternately reporting to the base station (BS) that there is data waiting for transmission and reporting that there is no data waiting for transmission. the method according to any of claims 1 3 including the step of applying the communication patterns used, characterized in that the. 4. A method according to any of claims 1-3 , comprising the step of prohibiting communication on the second connection before and after the selected time interval. The step of reporting to the base station (BS) includes a step of sending a report message to the base station (BS) at a certain time considering the scheduling delay time (latency) of the first connection. The method according to any one of claims 1 to 3 . A wireless device,
For communicating over a wide area wireless data network on and a wireless LAN (WLAN), a said radio frequency (RF) front end that will be set to exchange radio frequency (RF) signals,
A baseband circuit,
The baseband circuit is:
Establishing a first connection with the base station (BS) on the wide area wireless data network and a second connection on the wireless LAN (WLAN) via the radio frequency (RF) front end;
Selecting a time interval for communicating on the second connection;
In preparation for the selected time interval, by reporting to the base station (BS) that there is no data waiting to be transmitted from the wireless device before the time interval, to the base station (BS), To refrain from scheduling data transmissions from the wireless device to the base station (BS) on the first connection during the time interval ;
During the time interval, and communicate using the wireless device in the wireless LAN (WLAN) on the second on the connection, and,
In order to cause the base station (BS) to schedule transmission of the data waiting for transmission outside the time interval, data waiting for transmission is transmitted even when some data is waiting for transmission to the base station (BS). Report that there is no
A wireless device characterized by being set as follows. The baseband circuit, said in preparation for the time interval at the end of, the base station (BS) wherein is set to report that there is transmission waiting data from the wireless device to claim 8, characterized in that A wireless device according to 1. The radio according to claim 9 , wherein the baseband circuit is configured to report a data amount different from an actual size of the transmission-waiting data in order to control a size of transmission scheduled. apparatus. The wide area wireless data network operates according to the Long Term Evolution (LTE) standard, and the baseband circuit is configured to report that there is no data waiting to be transmitted by sending a buffer status report (BSR) message. , claim 8, characterized in that - 10 radio apparatus according to any one of. The baseband circuit alternately performs a step of reporting that there is data waiting to be transmitted to the base station (BS) and a step of reporting that there is no data waiting to be transmitted, so that the first connection and the first 2 of the connection is set to apply the communication patterns used alternately claim 8, characterized in that - 10 radio apparatus according to any one of. The baseband circuit, before and after the selected time interval is set so as to prohibit the communication on the second connection, according to claim 8, characterized in that - to one of the 10 The wireless device described. The baseband circuit is set to send a report message reporting that there is no data waiting to be transmitted to the base station (BS) at a certain time considering the scheduling delay time (latency) of the first connection. The wireless device according to any one of claims 8 to 10 .

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