US007193965B1
`
`(12) United States Patent
`US 7,193,965 B1
`Nevo et al.
`Mar. 20, 2007
`(45) Date of Patent:
`
`(10) Patent No.:
`
`(54) MULTI-WIRELESS NETWORK
`CONFIGURABLE BEHAVIOR
`
`6,633,848 B1 *
`2002/0136268 A1
`
`10/2003 Johnson et al.
`9/2002 Gan et a1.
`
`............. 704/277
`
`(75)
`
`Inventors: Ron Nevo, Hillsboro, OR (US);
`Xudong Zhao, Portland, OR (US);
`Dror Shindelman, Haifa (IL); Michael
`Vakulenko, Zichron Yaacov (IL);
`Ephraim Zehavi, Haifa (IL)
`
`(73) Assignee:
`
`Intel Corporation, Santa Clara, CA
`(US)
`
`FOREIGN PATENT DOCUMENTS
`
`EP
`EP
`EP
`GB
`W0
`W0
`
`0 944 176 Al
`1 220 499 A2
`1 225 709 Al
`2 327 016 A
`WO 01/35578 Al
`WO 01/76295 A2
`
`9/1999
`7/2002
`7/2002
`1/1999
`5/2001
`10/2001
`
`OTHER PUBLICATIONS
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`Negus, K J et al., Home RRTM and Swap: Wireless Networking for
`the Connected Home. Mobile Computing and Communications
`Review, v01. 2, NR. 4, pp. 28-36. ACM, New York, New York,
`United States.
`
`(21) Appl. No.: 09/565,215
`
`(22)
`
`Filed:
`
`May 4, 2000
`
`(51)
`
`Int. Cl.
`(2006.01)
`H04] 1/16
`(2006.01)
`H04] 3/14
`(52) US. Cl.
`...................... 370/230; 370/255; 370/447;
`370/461; 370/466
`(58) Field of Classification Search ................ 370/229,
`370/230, 230.1, 237, 255, 337, 447, 238,
`370/461, 466, 231, 468; 709/220, 230
`See application file for complete search history.
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`............... 370/249
`3/1997 Biegel et a1.
`5,608,720 A *
`4/1998 Abramson .................. 370/342
`5,745,485 A *
`7/1998 Hulyalkar et a1.
`....... 370/310.2
`5,787,080 A *
`6,463,470 B1 * 10/2002 Mohaban et a1.
`........... 709/223
`6,484,261 B1 *
`ll/2002 Wiegel
`....................... 713/201
`
`* cited by examiner
`
`Primary Examinerilohn Pezzlo
`Assistant Examinerilnder Pal Mehra
`
`(74) Attorney, Agent, or FirmiBlakely, Sokoloif, Taylor &
`Zafman LLP
`
`(57)
`
`ABSTRACT
`
`Techniques for supporting multiple potentially overlapping
`wireless protocols with a single electronic system are dis-
`closed. In the description that follows,
`the overlapping
`protocols are Bluetooth and IEEE 802.11 for wireless net-
`working; however, other overlapping protocols can be sup-
`ported in a similar manner. A transaction control policy and
`a collision map are provided to determine which protocol to
`enable/disable when a conflict arises. Based on the transac-
`
`tion control policy and the collision map, one or more
`transceivers that operate according to the wireless protocols
`can be selectively enabled/disabled to avoid actual conflicts.
`
`25 Claims, 6 Drawing Sheets
`
`
`TRANSACTION CONTROL
`
`POLICY
`@
`
`
`
`WLAN
`BLUETOOTH
`
`
`TRANSACTION
`TRANSACTION
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`
`@
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`fl;BACKOFF
`
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`TRANSCEIVER
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`
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`
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`
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`

`

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`U.S. Patent
`
`Mar. 20, 2007
`
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`US 7,193,965 B1
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`Mar. 20, 2007
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`Mar. 20, 2007
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`U.S. Patent
`
`Mar. 20, 2007
`
`Sheet 5 of 6
`
`US 7,193,965 B1
`
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`

`U.S. Patent
`
`Mar. 20, 2007
`
`Sheet 6 of 6
`
`US 7,193,965 B1
`
`FIG. 6
`
`RECEIVE RELEVANT
`
`POLICY ENTRIES
`
`m
`
`SELECT A POLICY
`
`ENTRY
`
`5A)
`
`§£L0
`
`ENABLE/D ISABLE
`
`WIRELESS TRANSCEIVER(S)
`BASED ON ENTRY
`
`gag
`
`TRANSMIT/ RECEIVE
`
`MESSAGE
`
`7
`
`

`

`1
`MULTI-WIRELESS NETWORK
`CONFIGURABLE BEHAVIOR
`
`FIELD OF THE INVENTION
`
`invention relates to the field of wireless
`The present
`communication. More specifically,
`the present
`invention
`relates to the problem of concurrent wireless voice and data
`communication with multiple communication partners of
`different wireless communication protocols.
`
`BACKGROUND OF THE INVENTION
`
`Several wireless communications protocols are available
`for use with electronic systems such as computer systems,
`personal digital assistants (PDAs),
`telephones, networks,
`and other devices. These wireless communications protocols
`include, but are not limited to, IEEE 802.11 direct sequence
`spread spectrum, IEEE 802.11 frequency hopping spread
`spectrum, Bluetooth, Home RF, also known as Shared
`Wireless Access Protocol (SWAP) and HIPERLAN, which
`is a European wireless LAN standard.
`In many situations, it is desirable for a single electronic
`system to support multiple wireless communications proto-
`cols concurrently. For example, a computer system may
`support an IEEE 802.11 protocol for wireless networking
`and Bluetooth for peripheral devices. A telephone system
`may support Bluetooth and SWAP. Unfortunately, the vari-
`ous protocols can overlap in time and frequency causing
`conflicts that can result in loss of data or otherwise disrupt
`operation. Therefore, some technique is desired to resolve
`conflicts between concurrently operating wireless protocols.
`
`SUMMARY OF THE INVENTION
`
`In one embodiment, an apparatus includes a first trans-
`ceiver to transmit/receive data according to a first protocol
`and a second transceiver to transmit/receive data according
`to a second protocol. Amemory to store a transaction control
`policy to indicate whether the first transceiver transmits/
`receives or the second transceiver transmits/receives if a
`
`conflict exists between the first protocol and the second
`protocol. A control circuit is coupled to receive at least a
`portion of the policy from the memory. The control circuit
`is also coupled to the first transceiver and to the second
`transceiver, the control circuit selectively enables/disables
`the first transceiver and the second transceiver according to
`the transaction control policy.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The invention is illustrated by way of example, and not by
`way of limitation,
`in the figures of the accompanying
`drawings in which like reference numerals refer to similar
`elements.
`
`FIG. 1 is a block diagram of one embodiment of an
`electronic system.
`FIG. 2 is a logical diagram of one embodiment of a
`wireless communications interface supporting IEEE 802.11
`and Bluetooth.
`
`FIG. 3 is a block diagram of one embodiment of a
`Bluetooth transmission control circuit.
`
`10
`
`15
`
`20
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`25
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`30
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`35
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`40
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`45
`
`50
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`55
`
`60
`
`FIG. 4 is one embodiment of a state diagram for a WLAN
`transceiver.
`
`65
`
`FIG. 5 is a block diagram of one embodiment of an
`WLAN transmission control circuit.
`
`US 7,193,965 B1
`
`2
`
`FIG. 6 is a flow diagram for concurrent transmissions of
`voice and/or data according to two possibly conflicting
`protocols.
`
`DETAILED DESCRIPTION
`
`In the following description, for purposes of explanation,
`numerous specific details are set forth in order to provide a
`thorough understanding of the invention. It will be apparent,
`however, to one skilled in the art that the invention can be
`practiced without these specific details. In other instances,
`structures and devices are shown in block diagram form in
`order to avoid obscuring the invention.
`Reference in the specification to “one embodiment” or
`“an embodiment” means that a particular feature, structure,
`or characteristic described in connection with the embodi-
`ment is included in at least one embodiment of the invention.
`
`The appearances of the phrase “in one embodiment” in
`various places in the specification are not necessarily all
`referring to the same embodiment.
`Techniques for supporting multiple potentially overlap-
`ping wireless protocols with a single electronic system are
`disclosed. Overlapping wireless protocols are two or more
`protocols in that use, or potentially use, the same frequency
`at
`the same time for operation. In the description that
`
`follows, the overlapping protocols are Bluetooth and IEEE
`802.11 for wireless networking; however, other overlapping
`protocols can be supported in a similar manner. Atransaction
`control policy and a collision map are provided to determine
`which protocol
`to enable/disable when a conflict arises.
`Based on the transaction control policy and the collision
`map, one or more transceivers that operate according to the
`wireless protocols can be selectively enabled/disabled to
`avoid actual conflicts.
`FIG. 1 is a block diagram of one embodiment of an
`electronic system. The electronic system illustrated in FIG.
`1 is intended to represent a range of electronic systems (e. g.,
`desktop computer system, laptop computer system, set top
`box, personal digital assistant, cordless telephone, cellular
`telephone). Alternative electronic systems can include more,
`fewer and/or different components.
`Electronic system 100 includes bus 101 or other commu-
`nication device to communicate information, and processor
`102 coupled to bus 101 to process information. While
`electronic system 100 is illustrated with a single processor,
`electronic system 100 can include multiple processors and/
`or co-processors. Electronic system 100 further includes
`random access memory (RAM) or other dynamic storage
`device 104 (referred to as main memory), coupled to bus 101
`to store information and instructions to be executed by
`processor 102. Main memory 104 also can be used to store
`temporary variables or other intermediate information dur-
`ing execution of instructions by processor 102.
`Electronic system 100 also includes read only memory
`(ROM) and/or other static storage device 106 coupled to bus
`101 to store static information and instructions for processor
`102. Data storage device 107 is coupled to bus 101 to store
`information and instructions. Data storage device 107 such
`as a magnetic disk or optical disc and corresponding drive
`can be coupled to electronic system 100.
`Electronic system 100 can also be coupled via bus 101 to
`display device 121, such as a cathode ray tube (CRT) or
`liquid crystal display (LCD), to display information to a
`electronic user. Alphanumeric input device 122, including
`alphanumeric and other keys, is typically coupled to bus 101
`to communicate information and command selections to
`
`processor 102. Another type of user input device is cursor
`
`8
`
`

`

`US 7,193,965 B1
`
`3
`control 123, such as a mouse, a trackball, or cursor direction
`keys to communicate direction information and command
`selections to processor 102 and to control cursor movement
`on display 121.
`Electronic system 100 further includes network interface
`130 to provide access to a network, such as a local area
`network.
`In one embodiment, network interface 130
`includes one or more transceivers (not shown in FIG. 1) that
`provide transactions (transmit and/or receive) according to
`multiple wireless protocols. These wireless protocols
`include, but are not limited to, IEEE 802.11 direct sequence
`spread spectrum, IEEE 802.11 frequency hopping spread
`spectrum, Bluetooth, Home RF, also known as Shared
`Wireless Access Protocol (SWAP).
`Instructions are provided to memory from a storage
`device, such as magnetic disk, a read-only memory (ROM)
`integrated circuit, CD-ROM, DVD, via a remote connection
`(e. g., over a network via network interface 130) that is either
`wired or wireless, etc. In alternative embodiments, hard-
`wired circuitry can be used in place of or in combination
`with software instructions to implement the present inven-
`tion. Thus, the present invention is not limited to any specific
`combination of hardware circuitry and software instructions.
`A machine-readable medium includes any mechanism
`that provides (i.e., stores and/or transmits) information in a
`form readable by a machine (e.g., a computer). For example,
`a machine-readable medium includes read only memory
`(ROM); random access memory (RAM); magnetic disk
`storage media; optical storage media; flash memory devices;
`electrical, optical, acoustical or other form of propagated
`signals (e.g., carrier waves, infrared signals, digital signals).
`FIG. 2 is a logical diagram of one embodiment of a
`wireless communications interface supporting IEEE 802.11
`and Bluetooth. While communication is described in terms
`of supporting IEEE 802.11 (WLAN) and Bluetooth concur-
`rently, other potentially overlapping protocols can be sup-
`ported in a similar manner.
`Transaction control policy 200 is provided to Bluetooth
`transaction control 210 and to wireless local area network
`(WLAN) transaction control 220. Bluetooth transaction con-
`trol 210 is described in greater detail below with respect to
`FIG. 3. WLAN transaction control 220 is described in
`greater detail below with respect to FIG. 5. In one embodi-
`ment, transaction control policy 200 is stored in a dynamic
`memory of an electronic system (e.g., main memory 104 of
`electronic system 100); however, in alternate embodiments,
`transaction control policy 200 can be stored in another
`storage device (e.g., ROM 106 of electronic system 100, a
`memory (not shown in FIG. 1) within network interface 130
`of electronic system 100).
`Bluetooth transaction control 210 receives Bluetooth
`(BT) state information from Bluetooth transceiver 230.
`Bluetooth transaction control 210 also generates an enable
`
`10
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`15
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`20
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`25
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`30
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`35
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`45
`
`4
`
`(ENAB) signal that is used to enable and disable Bluetooth
`transceiver 230. Bluetooth transceiver 230 generates a trans-
`action time (Tx_TIME) signal that indicates valid transac-
`tion times for Bluetooth transceiver 230 according to the
`Bluetooth protocol.
`In one
`embodiment ENAB and
`Tx_TIME are input to AND gate 235. The signal output by
`AND gate 235 enables/disables Bluetooth transceiver 230.
`Other logic configurations can be used to accomplish the
`same result.
`WLAN transaction control 220 receives WLAN state
`information from WLAN transceiver 240. WLAN transac-
`tion control 220 also generates an enable (ENAB) signal that
`is used to enable and disable WLAN transceiver 240.
`WLAN transceiver 240 generates a backolf (BACKOFF)
`signal that indicates whether WLAN transceiver 240 should
`backofl
`transmitting.
`In one embodiment ENAB and
`BACKOFF are input to AND gate 245. The signal output by
`AND gate 245 enables/disables WLAN transceiver 240.
`Other logic configurations can be used to accomplish the
`same result.
`
`Bluetooth state information is provided to WLAN trans-
`action control 220 and WLAN state information is provided
`to Bluetooth transaction control 210. Based on the state of
`the opposing transceiver and transaction policy 200, a trans-
`ceiver can be controlled to operate concurrently with another
`potentially conflicting protocol in a non-conflicting manner.
`Control of the various transceivers and transaction policy
`200 are described in greater detail below.
`FIG. 3 is a block diagram of one embodiment of a
`Bluctooth transmission control circuit. In onc cmbodimcnt
`
`transaction control policy 200 is stored in the memory of the
`electronic device (e.g., main memory 104) that communi-
`cates in a wireless manner. In alternate embodiments, policy
`table can be stored in a local memory (e.g., a memory of
`network interface 130) or in any other manner.
`In one embodiment,
`transaction control policy 200 is
`stored in the form of one or more policy tables, such as
`policy table 300. In one embodiment, control circuit 320
`receives a column of policy table 300 for each Bluetooth
`message to be processed. The column is selected based on
`the type of Bluetooth message to be processed. One example
`of policy table 300 is illustrated below in Table 1; however,
`other tables can also be used. In Table 1, an entry of “1”
`indicates that the Bluetooth transaction is enabled in the case
`of a conflict, a “0” indicates that the Bluetooth transaction is
`disabled in the case of a conflict, and a “X” is a don’t care
`state. For Table 1 as well as the state diagram of FIG. 4, for
`IEEE 802.11 states, “DCF” refers to “distributed coordi-
`nated functions,” which are transactions when there is no
`network master and “PCF” refers to “point coordinated
`functions,” which are transactions when there is a network
`master. DCF and PCF are known to those skilled in the art
`
`and are defined in the IEEE 802.11 standard.
`
`TABLE 1
`
`Transaction control policy Table Example for IEEE 802.11 and Bluetooth.
`Bluetooth
`Msg.
`Type
`IEEE
`802.11
`State
`
`SCO
`Tx
`Low Page
`1
`1
`
`SCO
`Tx
`1
`
`Snifl
`Hold
`Link
`Estab. Mode Mode
`1
`1
`1
`
`POLL ACL
`1
`1
`
`SCO
`Rx
`X
`
`State #
`
`401
`
`402
`
`403
`
`DCF
`IDLE
`DCF PL
`Rx
`DCF Rx
`Current
`
`1
`
`1
`
`1
`
`0
`
`1
`
`1
`
`1
`
`1
`
`1
`
`1
`
`1
`
`1
`
`1
`
`0
`
`1
`
`0
`
`X
`
`X
`
`SCO
`Rx
`Low
`X
`
`X
`
`X
`
`9
`
`

`

`US 7,193,965 B1
`
`5 T
`
`ABLE 1-continued
`
`State #
`404
`
`405
`
`406
`
`407
`
`408
`409
`
`410
`
`SCO
`TX
`
`SCO
`TX
`Low Page
`1
`1
`
`Hold Sniff
`Link
`Es ab. Mode Mode
`1
`1
`
`POLL ACL
`1
`1
`
`SCO
`RX
`Low
`X
`
`SCO
`RX
`X
`
`1
`
`0
`
`0
`
`0
`0
`
`0
`
`1
`
`0
`
`0
`
`0
`0
`
`0
`
`0
`
`0
`
`1
`
`0
`
`0
`
`0
`0
`
`0
`
`1
`
`0
`
`0
`
`0
`0
`
`0
`
`0
`
`0
`
`0
`
`0
`0
`
`0
`
`0
`0
`
`0
`
`0
`
`0
`
`0
`0
`
`0
`
`0
`0
`
`X
`
`1
`
`X
`
`1
`X
`
`1
`
`X
`X
`
`X
`
`0
`
`X
`
`0
`X
`
`0
`
`X
`X
`
`Transaction control policy Table Example for IEEE 802.11 and Bluetooth.
`Blue ooth
`Msg.
`Type
`IE 3E
`802.11
`State
`)C : RX
`0 1er
`)C : RX
`Broadcast
`)C : TX
`ACK
`)C : RX
`Fragment
`)C : TX
`)C : RX
`ACK
`)C : TX
`Fragment
`PCF Idle
`)C 5 PL
`RX
`)C : RX
`Current
`)C : RX
`0 1er
`)C : RX
`Broadcast
`)C : TX
`
`
`
`0
`
`0
`
`1
`1
`
`1
`
`1
`
`0
`
`0
`
`1
`1
`
`1
`
`1
`
`0
`
`0
`
`0
`
`1
`
`0
`
`0
`
`0
`
`1
`
`0
`
`0
`
`X
`
`X
`
`X
`
`1
`
`X
`
`X
`
`X
`
`0
`
`
`
`
`
`
`411
`412
`
`413
`
`414
`
`415
`
`416
`
`
`
`1
`0
`
`1
`
`1
`
`1
`
`0
`
`1
`1
`
`1
`
`1
`
`0
`
`0
`
`Control circuit 300 selects an entry from the column
`received based on the WLAN state received from WLAN
`
`transceiver 310. A state diagram corresponding to the states
`ofTable 1 is provided in FIG. 4. In one embodiment, WLAN
`transceiver 310 operates according to IEEE 802.11 proto-
`cols; however, other protocols can also be used.
`For example, if a Bluetooth message is a SCO transmit
`(Tx), control circuit 320 receives the column from Table 1
`corresponding to SCO TX. If the IEEE 802.11 WLAN
`message to be transmitted is a DCF TX message, control
`circuit 320 selects the corresponding entry from the column
`received. In the example of Table 1, the entry is a “1”, so
`control circuit 320 outputs a logical “1” to OR gate 350.
`Collision map 340 provides a second input to OR gate
`350. Collision map 340 determines the frequency to be used
`for the Bluetooth message and compares the frequency to
`the frequency range used for WLAN transmissions. Colli-
`sion map 340 outputs a signal indicating whether a collision
`(or conflict) will occur (COLLISION CURRENT SLOT
`signal). In one embodiment, WLAN transceiver 310 trans-
`mits and receives messages using a 22 MHZ frequency range
`centered around a predetermined center frequency. In an
`alternate embodiment, WLAN transceiver 310 transmits and
`receives messages using a 16 MHZ frequency range; how-
`ever, other frequency ranges can be used based on, for
`example, the filtering characteristics used.
`The output of OR gate 350 generates an enable (BT
`ENABLE) signal
`to Bluetooth transceiver 330, which
`enables Bluetooth transceiver 330 when asserted. The BT
`
`ENABLE signal is also input to AND gate 360. AND gate
`360 logically ANDs the BT ENABLE signal with a signal
`(Tx ACTIVE) from WLAN transceiver 310 that indicates
`whether WLAN transceiver 310 is currently transmitting a
`message. AND gate 360 generates the WLAN ABORT
`signal, which aborts the transmission of WLAN transceiver
`310.
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`In one embodiment, WLAN transceiver 310 also outputs
`a signal (WLAN STATE) that indicates the state of WLAN
`transceiver 310. One embodiment of a state diagram describ-
`ing the states of WLAN transceiver 310 is provided with
`respect to FIG. 4.
`In one embodiment, Bluetooth transceiver 330 generates
`a Tx SLOT START signal that is provided to control circuit
`320 to indicate the start of a message transmission by
`Bluetooth transceiver 330. Control circuit 320 can use the
`
`Tx SLOT START signal, for example, to begin processing of
`a subsequent message.
`FIG. 4 is one embodiment of a state diagram for a WLAN
`transceiver. State 401 is the idle (DCF IDLE) state where the
`state machine begins operation or the state to which the state
`machine returns after processing a message. WLAN mes-
`sages are transmitted in states 408410.
`At the start of a message transmission, the state machine
`transitions to state 408 (DCF Tx) for transmission of the
`WLAN message or a fragment of the WLAN message. At
`the end of the message transmission,
`the state machine
`transitions to state 409 (DCF Rx ACK) to receive an
`acknowledge message from the destination of the transmis-
`sion of state 408. If all fragments are transmitted, the state
`machine returns to state 401. Otherwise, the state machine
`transmits fragments in state 410 (DCF Tx Fragment) and
`receives acknowledgments in state 409 until the message is
`completely transmitted.
`If a preamble of a message is received in state 401, the
`state machine transitions to state 402 (DCF PL Rx). If the
`preamble is a current message, the state machine transitions
`to state 403 to receive the message or a fragment of the
`message. The state machine causes an acknowledge mes-
`sage to the message or message fragment to be sent in state
`406 (DCF Tx ACK). If additional fragments are to be
`received, the state machine transitions to state 407 (DCF Rx
`Fragment). Fragments are received and acknowledged in
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`US 7,193,965 B1
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`7
`states 406 and 407 until the message is complete, at which
`time the state machine returns to state 401.
`
`If, in state 402, the preamble indicates a broadcast mes-
`sage, the state machine transitions to state 405 (DCF Rx
`Broadcast) to receive the broadcast. If the message is not a
`Beacon signal, the broadcast message is received in state
`405 and the state machine returns to state 401.
`
`If, in state 405, the message is a Beacon signal, the state
`machine transitions to state 411 (PCF IDLE). The state
`machine moves to PCF mode, which corresponds to a
`network master. When a preamble is detected in state 411,
`the state machine transitions to state 412 (PCF PL Rx). If, in
`state 412, the preamble is for a broadcast message, the state
`machine transitions to state 415 (PCF Rx Broadcast) to
`receive the broadcast message. The state machine then
`returns to state 411 unless the broadcast message ends the
`PCP state, in which case the state machine returns to state
`401.
`
`If, in state 411, the preamble is for a current message, the
`state machine transitions to state 413 (PCF Rx Current) to
`begin receiving the message. Message fragments are
`received in state 413 and acknowledgments are transmitted
`in state 416 (PCF Tx) until the end of the message (EOM),
`when the state machine returns to state 411.
`
`If, in state 411, the message is an “other” type of message,
`which is for any other type of message, the state machine
`transitions to state 414 for receipt of the message. The state
`machine then returns to state 411.
`
`If, in state 402, the message is an “other” type of message,
`which is for any other type of message, the state machine
`transitions to state 404 for receipt of the message. The state
`machine then returns to state 401.
`
`FIG. 5 is a block diagram of one embodiment of an
`WLAN transmission control circuit. Transaction control
`policy 200 provides Bluetooth (BT) priorities corresponding
`to the Bluetooth messages to be transmitted. In one embodi-
`ment, priorities for three Bluetooth messages (the current
`message, the next message and the subsequent (or after next)
`message) are used in controlling transmissions by WLAN
`transceiver 310; however, any number of message priorities
`can be used in a similar manner. In one embodiment, the
`Bluetooth priorities are columns from Table 1. In alternate
`embodiments, Bluetooth priorities can be determined in
`another manner. The Bluetooth priorities are input to selec-
`tors 510, 520, and 530.
`The message type of the WLAN message is used to
`provide the selection signals for selectors 510, 520, and 530.
`The selection signals select the entry in the column corre-
`sponding to the WLAN message type. The output signal
`from selectors 510, 520, and 530 are the entries from Table
`1 that correspond to the Bluetooth column and the WLAN
`row. The output signals from selectors 510, 520, and 530 are
`input to AND gates 515, 525 and 535, respectively.
`AND gates 515, 525 and 535 also receive entries from
`collision map 340 for the current Bluetooth slot, the next
`Bluetooth slot and the after next Bluetooth slot, respectively.
`The respective entries from collision map 340 indicate
`whether a conflict exists for the WLAN message and the
`current Bluetooth slot, the next Bluetooth slot and the after
`next Bluetooth slot.
`
`AND gate 515 receives, as a third input (BT Modem
`Active) signal, an indication of whether Bluetooth trans-
`ceiver 330 is active. The WLAN message duration and the
`time to the next Bluetooth slot are input to comparator 540.
`Similarly, the WLAN message duration and the time to the
`after next Bluetooth slot are input to comparator 545. The
`
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`output signals from comparators 540 and 545 are input to
`AND gates 525 and 535, respectively.
`The output signals generated by AND gates 515, 525 and
`535 indicate whether a conflict exists between the WLAN
`
`message and a current Bluetooth message as well as the next
`Bluetooth message and the after next Bluetooth message if
`the WLAN message is long enough to overlap multiple
`Bluetooth messages. AND gate 550 receives, as input sig-
`nals, the output signals from AND gates 515, 525 and 535
`as well as an Access Permitted signal from WLAN trans-
`ceiver 310. The Access Permitted signal indicates whether
`WLAN transceiver 310 can be disabled because of a conflict
`
`with a Bluetooth message.
`If no conflicts exist, based on transaction control policy
`200, collision map 340 and the timing information WLAN
`transceiver 310 is enabled by AND gate 550. If a conflict
`exists, WLAN transceiver 310 is disabled by AND gate 550.
`FIG. 6 is a flow diagram for concurrent transmissions of
`voice and/or data according to two possibly conflicting
`protocols. Relevant policy entries are received at 610. In one
`embodiment, a selected column from a policy table 's
`received. The column can be selected, for example, based on
`a type of message (e.g., Bluetooth SCO transmission, IEEE
`802.11 DCF transmission), or on other criteria. In an alte‘-
`nate embodiment, a complete policy table can be received.
`A policy entry from the relevant policy entries is selected
`at 620.
`In one embodiment, a type of message to be
`transmitted can be used to select the specific entry to be
`used. For example, if the type of Bluetooth message is used
`to select the relevant entries, the type of WLAN message is
`used to select the entry from the relevant entries. The reverse
`can also be used. That is, if the type of WLAN message is
`used to select the relevant entries, the type of Bluetooth
`message is used to select the entry from the relevant entries.
`One or more wireless transceivers are enabled or disables
`
`
`
`based, at least in part, on the selected entry at 630. For
`example, if both a WLAN message and a Bluetooth message
`are to be transmitted at the same time and on overlapping
`frequencies, one of the WLAN transceiver and the Bluetooth
`transceiver is enabled and the other transceiver is disabled.
`
`The message(s) are transmitted/received at 640.
`In the foregoing specification,
`the invention has been
`described with reference to specific embodiments thereof. It
`will, however, be evident that various modifications and
`changes can be made thereto without departing from the
`broader spirit and scope of the invention. The specification
`and drawings are, accordingly, to be regarded in an illus-
`trative rather than a restrictive sense.
`What is claimed is:
`
`1. An apparatus comprising:
`a first transceiver to transmit/receive data according to a
`first wireless communication protocol;
`a second transceiver to transmit/receive data according to
`a second wireless communication protocol;
`a memory to store a transaction control policy to indicate
`whether the first transceiver transmits/receives or the
`second transceiver transmits/receives if a conflict exists
`
`between the first wireless communication protocol and
`the second wireless communication protocol; and
`a control circuit coupled with the memory to receive at
`least a portion of the transaction control policy from the
`memory, wherein the portion of the transaction control
`policy received is based, at least in part, on a type of
`message to be transmitted by the first
`transceiver,
`wherein the control circuit is also coupled with the first
`transceiver and with the second transceiver, the control
`circuit to selectively enable/disable the first transceiver
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`US 7,193,965 B1
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`9
`and to selectively enable/disable the second transceiver
`according to the portion of the transaction control
`policy.
`2. The apparatus of claim 1 wherein the transaction
`control policy comprises a policy table and the apparatus
`further comprises a collision map.
`3. The apparatus of claim 1 wherein the portion of the
`transaction control policy includes a set of entries,
`the
`control circuit to select an entry from the set of entries based
`on the state of the second transceiver, wherein the control
`circuit further comprises facilities to selectively enable/
`disable the first transceiver and to selectively enable/disable
`the second transceiver according to the selected entry.
`4. The apparatus of claim 1, wherein the first wireless
`communication protocol and the second wireless commu-
`nication protocol comprise different ones of the following
`protocols: IEEE 802.11 direct sequence spread spectrum,
`IEEE 802.11 frequency hopping spread spectrum, Blue-
`tooth, SWAP and HlPERLAN.
`5. The apparatus of claim 1, wherein the first wireless
`communication protocol comprises a synchronous protocol
`and the second wireless communication protocol comprises
`an asynchronous protocol.
`6. An apparatus comprising:
`a transceiver to transmit/receive data according to a first
`wireless communication protocol and to transmit/re-
`ceive data according to a second wireless communica-
`tion protocol;
`a memory to store a transaction control policy to indicate
`whether the transceiver transmits/receives according to
`the first wireless communication protocol or according
`to the second wireless communication protocol if a
`conflict exists between the first wireless communica-
`
`tion protocol and the second wireless communication
`protocol; and
`a control circuit coupled with the memory to receive at
`least a portion of the transaction control policy from the
`memory, wherein the portion of the transaction control
`policy received is based, at least in part, on a type of
`message to be transmitted according to the first wireless
`communication protocol, wherein the control circuit is
`also coupled with, said transceiver, the control circuit to
`selectively enable/disable said transceiver according to
`the portion of the transaction control policy.
`7. The apparatus of claim 6 wherein the transaction
`control policy comprises a policy table and the apparatus
`further comprises a collision map.
`8. The apparatus of claim 6 wherein the portion of the
`transaction control policy includes a set of entries,
`the
`control circuit to select an entry from the set of entries based
`on a type of message to be transmitted according to the
`second wireless communication protocol, wherein the con-
`trol circuit further comprises facilities to selectively enable/
`disable said transceiver according to the selected entry.
`9. The apparatus of claim 6, wherein the first wireless
`communication protocol and the second wireless commu-
`nication protocol comprise different ones of the following
`protocols: IEEE 802.11 direct sequence spread spectrum,
`IEEE 802.11 frequency hopping spread spectrum, Blue-
`tooth, SWAP and HlPERLAN.
`10. The apparatus of claim 6, wherein the first wireless
`communication protocol comprises a synchronous protocol
`and the second wireless communication protocol comprises
`an asynchronous protocol.
`11. A method comprising:
`s