PATENT DOCUMENT

Publication Number: US-8781519-B2
Application Number: US-201213628013-A
Country: US
Kind Code: B2

Title: Transmission power modulation to facilitate in-device coexistence between wireless communication technologies

Abstract:
A method of modulating transmission power to facilitate in-device coexistence between wireless communication technologies is provided. The method can include determining a scheduled time period during which data is received by a device via a first wireless communication technology. The method can further include reducing a transmission power of a transmission from the device via a second wireless communication technology to a threshold level prior to the scheduled time period and controlling the transmission power so that the transmission power does not exceed the threshold level during the scheduled time period. The method can additionally include, subsequent to the time period, increasing the transmission power to a level exceeding the threshold level.

Claims:
What is claimed is: 
     
       1. A method comprising:
 determining, with a processor, a scheduled time period during which data is received by a device via Bluetooth; 
 reducing a transmission power of a cellular transmission from the device to a threshold level prior to the scheduled time period and controlling the transmission power so that the transmission power does not exceed the threshold level during the scheduled time period, wherein the transmission power is reduced in an instance in which the data received during the scheduled time period comprises data satisfying a threshold priority criterion; and 
 subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. 
 
     
     
       2. The method of  claim 1 , wherein the threshold level is a pre-determined power level at which the cellular transmission does not inhibit concurrent data reception via Bluetooth. 
     
     
       3. The method of  claim 1 , further comprising receiving a message from a Bluetooth control module, the message including an indication of the scheduled time period, and wherein determining the scheduled time period comprises determining the scheduled time period based at least in part on the indication. 
     
     
       4. The method of  claim 1 , wherein the cellular transmission comprises a transmission in accordance with one of a Long Term Evolution (LTE) cellular communication technology, a Universal Mobile Telecommunications System (UMTS) cellular communication technology, a Global System for Mobile Communications (GSM) cellular communication technology, a Code Division Multiple Access (CDMA) cellular communication technology, or a CDMA 2000 cellular communication technology. 
     
     
       5. The method of  claim 1 , wherein data satisfying the threshold priority criterion comprises a Link Manager Protocol (LMP) message, wherein the transmission power is not reduced for reception of data other than LMP messages. 
     
     
       6. The method of  claim 1 , further comprising adjusting an operational parameter of a power amplifier applied to the cellular transmission to increase a linearity of the power amplifier during the scheduled time period. 
     
     
       7. An apparatus comprising:
 a first wireless transceiver configured to emit transmissions via a first wireless communication technology; and 
 processing circuitry coupled to the first wireless transceiver, wherein the processing circuitry is configured to: 
 determine a scheduled time period during which data is received by a second wireless transceiver co-located with the first wireless transceiver via a second wireless communication technology; 
 reduce a transmission power of a transmission emitted by the first wireless transceiver prior to the scheduled time period and control the transmission power so that the transmission power does not exceed the threshold level during the scheduled time period, wherein the transmission power is reduced in an instance in which the data received during the scheduled time period comprises data satisfying a threshold priority criterion; and 
 subsequent to the scheduled time period, increase the transmission power to a level exceeding the threshold level. 
 
     
     
       8. The apparatus of  claim 7 , wherein the processing circuitry is coupled to an interface, and wherein the processing circuitry is further configured to:
 receive, via the interface, a message sent by a control module configured to control the second wireless transceiver, the message including an indication of the scheduled time period; and 
 determine the scheduled time period at least in part by determining the scheduled time period based at least in part on the indication. 
 
     
     
       9. The apparatus of  claim 8 , wherein the apparatus is implemented on a chipset for the first wireless communication technology, wherein the control module comprises a chipset for the second wireless communication technology, and wherein the interface comprises an interface between the chipset for the first wireless communication technology and the chipset for the second wireless communication technology. 
     
     
       10. The apparatus of  claim 9 , wherein the chipset for the first wireless communication technology comprises a cellular chipset, and wherein the second wireless communication technology comprises a wireless communication technology utilizing an industrial, scientific, and medical (ISM) band. 
     
     
       11. The apparatus of  claim 7 , wherein the apparatus is implemented on a mobile communication device, the mobile communication device further comprising the second wireless transceiver. 
     
     
       12. A method comprising:
 determining a scheduled time period during which data is received by a device via a first wireless communication technology; 
 determining, with a processor, that a transmission power of a transmission from the device via a second wireless communication technology should be reduced to a threshold level during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period, wherein determining that the transmission power should be reduced comprises determining that the data to be received during the scheduled time period comprises data satisfying a threshold priority criterion; and 
 sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power so that it does not exceed the threshold level during the scheduled time period. 
 
     
     
       13. The method of  claim 12 , wherein the transmission power is not reduced for data that does not satisfy the threshold priority criterion. 
     
     
       14. The method of  claim 13 , wherein the first wireless communication technology comprises Bluetooth, and wherein determining that data to be received during the scheduled time period comprises data satisfying the threshold priority criterion comprises determining that a Link Manager Protocol (LMP) message is received during the scheduled time period, wherein the transmission power is not reduced for reception of data other than LMP messages. 
     
     
       15. The method of  claim 12 , wherein sending the message comprises sending a message from a control module for the first wireless communication technology to the control module for the second wireless communication technology via an interface between the control module for the first wireless communication technology and the control module for the second wireless communication technology. 
     
     
       16. The method of  claim 12 , further comprising determining a plurality of scheduled time periods during which data is received via the first wireless communication technology and the transmission power should be reduced to the threshold level, and wherein sending the message comprises sending a message including an indication of the plurality of scheduled time periods. 
     
     
       17. The method of  claim 16 , wherein determining the plurality of scheduled time periods comprises determining the plurality of scheduled time periods based at least in part on a schedule of reception time slots for a synchronous connection supported by the first wireless communication technology. 
     
     
       18. An apparatus comprising:
 a first wireless transceiver configured to receive data via a first wireless communication technology; and 
 processing circuitry coupled to the first wireless transceiver, wherein the processing circuitry is configured to: 
 determine a scheduled time period during which data is received by the first wireless transceiver; 
 determine that a transmission power of a transmission by a second wireless transceiver co-located with the first wireless transceiver via a second wireless communication technology should be reduced to a threshold level during the scheduled time period so that transmission by the second wireless transceiver does not inhibit data reception via the first wireless communication technology during the scheduled time period, wherein the transmission power is reduced in an instance in which the data received during the scheduled time period comprises data satisfying a threshold priority criterion; and 
 send a message to a control module configured to control the second wireless transceiver, the message including an indication of the scheduled time period to request that the control module reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power so that it does not exceed the threshold level during the scheduled time period. 
 
     
     
       19. The apparatus of  claim 18 , wherein the processing circuitry is further configured to determine that the transmission power should be reduced at least in part by determining that a control message is received during the scheduled time period, wherein the transmission power is not reduced for non-control messages. 
     
     
       20. The apparatus of  claim 18 , wherein the apparatus is implemented on a chipset for the first wireless communication technology, wherein the control module comprises a chipset for the second wireless communication technology, and wherein the processing circuitry is configured to send the message via an interface between the chipset for the first wireless communication technology and the chipset for the second wireless communication technology. 
     
     
       21. The apparatus of  claim 20 , wherein the apparatus is implemented on a mobile communication device, the mobile communication device further comprising the second wireless transceiver. 
     
     
       22. An apparatus comprising:
 first control circuitry for a first wireless communication technology; 
 second control circuitry for a second wireless communication technology; and 
 an interface configured to enable communication between the first control circuitry and the second control circuitry, 
 wherein the first control circuitry is configured to determine a scheduled time period during which data is received by a device via a first wireless communication technology and send a message over the interface to the second control circuitry to request that the second control circuitry reduce a transmission power of a transmission via the second wireless communication technology to a threshold level during the scheduled time period, wherein the transmission power is reduced in an instance in which the data received during the scheduled time period comprises data satisfying a threshold priority criterion; and 
 wherein the second control circuitry is configured to receive the message sent over the interface by the first control circuitry and, in response to the message, to reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level. 
 
     
     
       23. The apparatus of  claim 22 , wherein the first control circuitry is further configured to:
 determine whether the transmission power should be reduced to the threshold level during the scheduled time period; and 
 to send the message to the second control circuitry only in an instance in which it is determined that the transmission power should be reduced to the threshold level during the scheduled time period. 
 
     
     
       24. The apparatus of  claim 22 , wherein the second control circuitry is further configured to adjust an operational parameter of a power amplifier applied to the cellular transmission to increase a linearity of the power amplifier during the scheduled time period in response to the message.

Description:
FIELD OF THE DESCRIBED EMBODIMENTS 
     The described embodiments relate generally to wireless communications and more particularly to transmission power modulation to facilitate in-device coexistence between wireless communication technologies. 
     BACKGROUND 
     Many wireless communication devices support multiple wireless communication technologies and may concurrently communicate via multiple wireless communication technologies. In many instances, wireless communication technologies used by a device use adjacent, or at least proximate, channel bands. In such instances, energy from a band used by one technology can leak into a band used by another technology. This energy leakage can cause a problem known as adjacent channel interference. In many instances, adjacent channel interference can negatively impact the use of certain channel bands and, in severe cases, can render certain channel bands unusable. Accordingly, adjacent channel interference poses a problem for in-device coexistence of multiple wireless communication technologies. 
     A particularly troublesome adjacent channel interference problem can result in a scenario in which a device emits a transmission via a first wireless communication technology, referred to as an aggressor technology, while the device is receiving data via a second wireless communication technology, referred to as a victim technology. Data receipt by the victim technology can be damaged by the aggressor transmission, particularly in instances in which the aggressor technology uses a relatively high transmission power. In this regard, received packet errors, or even complete deafening of the victim technology receiver can result from the adjacent channel interference caused by the aggressor technology transmission. For example transmission of a cellular signal by a device at a time when a Bluetooth signal is received can deafen the Bluetooth receiver, causing errors and, in some cases, complete loss of the Bluetooth connection. 
     SUMMARY OF THE DESCRIBED EMBODIMENTS 
     Some embodiments disclosed herein reduce the occurrence of adjacent channel interference, including blocker interference, out-of-band emissions, and harmonic interference. In this regard, some example embodiments provide for transmission power modulation of transmissions by an aggressor wireless technology during a time period in which data is received via a victim technology. Additionally or alternatively, some example embodiments provide for increasing a linearity of a power amplifier applied to a transmission via an aggressor wireless technology during a time period in which data is received via a victim technology. Accordingly, such embodiments facilitate in-device coexistence between wireless communication technologies. Devices implementing various embodiments disclosed herein can experience reduced loss and corruption of received data due to reduced adjacent channel interference. Further, devices sending data to a device implementing an embodiment disclosed herein can experience benefits due to a reduction in lost data and, consequently, reduced retransmission of data. 
     In a first embodiment, a method is provided. The method of the first embodiment can include determining a scheduled time period during which data is received by a device via a first wireless communication technology; reducing a transmission power of a transmission from the device via a second wireless communication technology to a threshold level prior to the scheduled time period and controlling the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level; and subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. 
     In a second embodiment, an apparatus is provided. The apparatus of the second embodiment can include a first transceiver configured to emit transmissions via a first wireless communication technology and processing circuitry coupled to the first wireless transceiver. The processing circuitry can be configured to determine a scheduled time period during which data is received by a second wireless transceiver via a second wireless communication technology; reduce a transmission power of a transmission emitted by the first wireless transceiver prior to the scheduled time period and control the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level; and subsequent to the scheduled time period, increase the transmission power to a level exceeding the threshold level. 
     In a third embodiment, a computer program product is provided. The computer program product of the third embodiment can include at least one non-transitory computer readable storage medium having program code stored thereon. The program code can include program code for determining a scheduled time period during which data is received by a device via a first wireless communication technology; program code for reducing a transmission power of a transmission from the device via a second wireless communication technology to a threshold level prior to the scheduled time period and controlling the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level; and program code for, subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. 
     In a fourth embodiment, an apparatus is provided that can include means for determining a scheduled time period during which data is received by a device via a first wireless communication technology; means for reducing a transmission power of a transmission from the device via a second wireless communication technology to a threshold level prior to the scheduled time period and controlling the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level; and means for, subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. 
     In a fifth embodiment, a method is provided. The method of the fifth embodiment can include determining a scheduled time period during which data is received by a device via a first wireless communication technology; determining that a transmission power of a transmission from the device via a second wireless communication technology should be reduced to a threshold level during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power so that it does not exceed the threshold level during the scheduled time period. 
     In a sixth embodiment, an apparatus is provided. The apparatus of the sixth embodiment can include a first transceiver configured to receive data via a first wireless communication technology and processing circuitry coupled to the first wireless transceiver. The processing circuitry can be configured to determine a scheduled time period during which data is received by the first wireless transceiver; determine that a transmission power of a transmission by a second wireless transceiver via a second wireless communication technology should be reduced to a threshold level during the scheduled time period so that transmission by the second wireless transceiver does not inhibit data reception via the first wireless communication technology during the scheduled time period; and send a message to a control module configured to control the second wireless transceiver, the message including an indication of the scheduled time period to request that the control module reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power so that it does not exceed the threshold level during the scheduled time period. 
     In a seventh embodiment, a computer program product is provided. The computer program product of the seventh embodiment can include at least one non-transitory computer readable storage medium having program code stored thereon. The program code can include program code for determining a scheduled time period during which data is received by a device via a first wireless communication technology; program code for determining that a transmission power of a transmission from the device via a second wireless communication technology should be reduced to a threshold level during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and program code for sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power so that it does not exceed the threshold level during the scheduled time period. 
     In an eighth embodiment, an apparatus is provided that can include means for determining a scheduled time period during which data is received by a device via a first wireless communication technology; means for determining that a transmission power of a transmission from the device via a second wireless communication technology should be reduced to a threshold level during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and means for sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power so that it does not exceed the threshold level during the scheduled time period. 
     In a ninth embodiment, an apparatus is provided that can include first control circuitry for a first wireless communication technology; second control circuitry for a second wireless communication technology; and an interface configured to enable communication between the first control circuitry and the second control circuitry. The first control circuitry can be configured to determine a scheduled time period during which data is received by a device via a first wireless communication technology and send a message over the interface to the second control circuitry to request that the second control circuitry reduce a transmission power of a transmission via the second wireless communication technology to a threshold level during the scheduled time period. The second control circuitry can be configured to receive the message sent over the interface by the first control circuitry and, in response to the message, to reduce the transmission power to the threshold level prior to the scheduled time period and control the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level. 
     In a tenth embodiment, a method is provided. The method of the tenth embodiment can include determining a scheduled time period during which data is received by a device via a first wireless communication technology; and adjusting an operational parameter of a power amplifier applied to a cellular transmission from the device to increase a linearity of the power amplifier during the scheduled time period. 
     In an eleventh embodiment, an apparatus is provided. The apparatus of the eleventh embodiment can include a first transceiver configured to emit transmissions via a first wireless communication technology and processing circuitry coupled to the first wireless transceiver. The processing circuitry can be configured to determine a scheduled time period during which data is received by a second wireless transceiver via a second wireless communication technology; and adjust an operational parameter of a power amplifier applied to a cellular transmission from the device to increase a linearity of the power amplifier during the scheduled time period. 
     In a twelfth embodiment, a computer program product is provided. The computer program product of the twelfth embodiment can include at least one non-transitory computer readable storage medium having program code stored thereon. The program code can include program code for determining a scheduled time period during which data is received by a device via a first wireless communication technology; and program code for adjusting an operational parameter of a power amplifier applied to a cellular transmission from the device to increase a linearity of the power amplifier during the scheduled time period. 
     In a thirteenth embodiment, an apparatus is provided that can include means for determining a scheduled time period during which data is received by a device via a first wireless communication technology; and means for adjusting an operational parameter of a power amplifier applied to a cellular transmission from the device to increase a linearity of the power amplifier during the scheduled time period. 
     In a fourteenth embodiment, a method is provided. The method of the fourteenth embodiment can include determining a scheduled time period during which data is received by a device via a first wireless communication technology; determining that a linearity of a power amplifier applied to a transmission from the device via a second wireless communication technology should be increased during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module increase the linearity of the power amplifier during the scheduled time period. 
     In a fifteenth embodiment, an apparatus is provided. The apparatus of the fifteenth embodiment can include a first transceiver configured to receive data via a first wireless communication technology and processing circuitry coupled to the first wireless transceiver. The processing circuitry can be configured to determine a scheduled time period during which data is received by the first wireless transceiver; determine that a linearity of a power amplifier applied to a transmission from the device via a second wireless communication technology should be increased during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and send a message to a control module configured to control the second wireless transceiver, the message including an indication of the scheduled time period to request that the control module increase the linearity of the power amplifier during the scheduled time period. 
     In a sixteenth embodiment, a computer program product is provided. The computer program product of the sixteenth embodiment can include at least one non-transitory computer readable storage medium having program code stored thereon. The program code can include program code for determining a scheduled time period during which data is received by a device via a first wireless communication technology; program code for determining that a linearity of a power amplifier applied to a transmission from the device via a second wireless communication technology should be increased during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and program code for sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module increase the linearity of the power amplifier during the scheduled time period. 
     In a seventeenth embodiment, an apparatus is provided that can include means for determining a scheduled time period during which data is received by a device via a first wireless communication technology; means for determining that a linearity of a power amplifier applied to a transmission from the device via a second wireless communication technology should be increased during the scheduled time period so that transmission via the second wireless communication technology does not inhibit data reception via the first wireless communication technology during the scheduled time period; and means for sending a message including an indication of the scheduled time period to a control module for the second wireless communication technology in advance of the scheduled time period to request that the control module increase the linearity of the power amplifier during the scheduled time period. 
     In an eighteenth embodiment, an apparatus is provided that can include first control circuitry for a first wireless communication technology; second control circuitry for a second wireless communication technology; and an interface configured to enable communication between the first control circuitry and the second control circuitry. The first control circuitry can be configured to determine a scheduled time period during which data is received by a device via a first wireless communication technology and send a message over the interface to the second control circuitry to request that the second control circuitry increase a linearity of a power amplifier applied to a transmission via the second wireless communication technology during the scheduled time period. The second control circuitry can be configured to receive the message sent over the interface by the first control circuitry and, in response to the message, to adjust an operational parameter of the power amplifier to increase the linearity of the power amplifier during the scheduled time period. 
     The above summary is provided merely for purposes of summarizing some example embodiments so as to provide a basic understanding of some aspects of the disclosure. Accordingly, it will be appreciated that the above described example embodiments are merely examples and should not be construed to narrow the scope or spirit of the disclosure in any way. Other embodiments, aspects, and advantages will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The described embodiments and the advantages thereof may best be understood by reference to the following description taken in conjunction with the accompanying drawings. These drawings are not necessarily drawn to scale, and in no way limit any changes in form and detail that may be made to the described embodiments by one skilled in the art without departing from the spirit and scope of the described embodiments. 
         FIG. 1  illustrates a prior art time domain view of an in-device coexistence problem between wireless communication technologies that can be addressed by various example embodiments. 
         FIG. 2  illustrates an example time domain view of transmission power modulation to facilitate in-device coexistence between wireless communication technologies in accordance with some example embodiments. 
         FIG. 3  illustrates an example transmission power waveform in accordance with some example embodiments. 
         FIG. 4  illustrates a block diagram of a mobile communication device in accordance with some example embodiments. 
         FIG. 5  illustrates interfaced chipsets configured to facilitate in-device coexistence between wireless communication technologies in accordance with some example embodiments. 
         FIG. 6  illustrates an example system in which some example embodiments can be implemented to facilitate in-device coexistence between wireless communication technologies. 
         FIG. 7  illustrates a flowchart according to an example method for performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 8  illustrates a flowchart according to another example method for performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 9  illustrates a flowchart according to an example method for enabling performance of transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 10  illustrates a flowchart according to a further example method for performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 11  illustrates examples of current biasing to achieve increased linearity of a power amplifier according to some example embodiments. 
         FIG. 12  illustrates a flowchart according to an example method for increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 13  illustrates a flowchart according to another example method for increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 14  illustrates a flowchart according to an example method for enabling increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 15  illustrates a flowchart according to a further example method for increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
         FIG. 16  illustrates a flowchart according to an example method for increasing linearity of a power amplifier and performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. 
     
    
    
     DETAILED DESCRIPTION OF SELECTED EMBODIMENTS 
     Representative applications of systems, methods, apparatuses, and computer program products according to the instant specification are described in this section. These examples are being provided solely to add context and aid in the understanding of the described embodiments. It will thus be apparent to one skilled in the art that the described embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the described embodiments. Other applications are possible, such that the following examples should not be taken as limiting. 
     In the following detailed description, references are made to the accompanying drawings, which form a part of the description and in which are shown, by way of illustration, specific embodiments in accordance with the described embodiments. Although these embodiments are described in sufficient detail to enable one skilled in the art to practice the described embodiments, it is understood that these examples are not limiting; such that other embodiments may be used, and changes may be made without departing from the spirit and scope of the described embodiments. 
     Some example embodiments address an in-device coexistence problem between wireless communication technologies. More particularly, some example embodiments described further herein address a situation in which a transmission is emitted by a device via an aggressor technology while the device is to receive data via a victim technology. In such situations, the aggressor technology transmissions can inhibit data reception via the victim technology, potentially resulting in received data errors, or in extreme cases, even completely deafening the victim technology receiver. For example, victim technology data reception can suffer from blocker interference in which the victim technology receiver can capture a high-power signal from an aggressor technology transmission that can desense the victim signal. As another example, victim technology data reception can suffer from interference from out-of-band (OOB) emissions in which an aggressor technology transmission can be in a band adjacent to nearby the victim technology band and the aggressor technology transmission can leak power into the victim technology band, thus raising the noise floor for the victim technology data reception. As a further example, victim technology data reception can suffer from interference from harmonics in which an aggressor technology transmission can result in harmonics from non-linear behavior placing an interfering power into the victim technology band. Various example embodiments disclosed herein and described further herein below can reduce the effects of blocker interference, OOB interference, and harmonics interference. 
       FIG. 1  illustrates a prior art time domain view of an in-device coexistence problem in which transmissions are emitted via an aggressor technology while data is received by a victim technology that can be addressed by various example embodiments. In this regard,  FIG. 1  illustrates a time domain sequence of reception (“R”) and transmission (“T”) periods for an aggressor technology and a victim technology that can be implemented on a mobile communication device and/or on other device configured to engage in wireless communications via multiple wireless communication technologies. It may be seen in  FIG. 1  that data reception  102  is scheduled to occur between time t 1  and time t 2 . However, as illustrated a transmission  104  via the aggressor technology occurs during a portion of the time period between t 1  and t 2 . As such, the data reception  102  can be damaged, as indicated by the cross-hatched pattern on the illustration of data reception  102 . Similarly, data reception  106  can also be damaged, as the transmission  108  via the aggressor technology overlaps the entirety of the time period between t 3  and t 4  during which the data reception  106  occurs. However, data reception  114  may proceed uninhibited, as the transmission  110  via the aggressor technology does not overlap the time period between t 5  and t 6  during which the data reception  106  occurs. 
     Concurrent transmissions via multiple wireless communication technologies can, in many instances, proceed without damaging adjacent channel interference. Thus, for example, overlapping transmissions  110  and  112  can proceed without interference damaging either transmission. Further, in the example scenario illustrated in  FIG. 1 , the transmission power of transmissions via the aggressor technology can be much greater than the transmission power of transmissions via the victim technology. Thus, while transmissions via the aggressor technology can inhibit concurrent reception via the victim technology, transmissions via the victim technology may not impact a concurrent reception via the aggressor technology. Thus, for example, while the transmission  116  via the victim technology overlaps the reception  118  via the aggressor technology, the reception  118  may not be inhibited by the transmission  116 . 
     The example illustrated in  FIG. 1  illustrates a common problem when a device communicates concurrently via cellular communications and a lower powered communication technology utilizing an industrial, scientific, and medical (ISM) band, such as Bluetooth. In such scenarios, the cellular transmissions can be much stronger than the Bluetooth transmissions. Accordingly, Bluetooth transmissions may not significantly impact cellular reception. However, cellular transmissions can prevent reception of Bluetooth packets. 
     In many instances, receptions via a victim technology are scheduled, and it may not be possible to shift scheduled reception intervals around transmissions via an aggressor technology. Similarly, the timing of transmissions via an aggressor technology can be fixed according to a schedule. For example, in instances in which the aggressor technology is a cellular communications technology, the timing of cellular transmissions by a device can be set by the cellular base station, which may not have any knowledge of scheduled reception periods for Bluetooth or other potential victim technology. Accordingly, collisions between cellular transmissions and victim technology reception periods, such as data reception periods  102  and  106  illustrated in the example of  FIG. 1  can result. 
     Several example embodiments described herein can address the problem illustrated in and described with respect to  FIG. 1 . In this regard, some example embodiments provide for determining a scheduled time period during which data is received via a victim technology and reduce a transmission power of a transmission via an aggressor technology such that it does not exceed a threshold level during the scheduled time period. The threshold level can be chosen such that the transmission via the aggressor technology does not inhibit concurrent data reception via the victim technology. In this regard, the threshold level can be chosen such that the transmission via the aggressor technology does not introduce errors in data received via the victim technology, prevent reception of data via the victim technology, or otherwise damage data reception via the victim technology. Further, the threshold level can be a transmission power level that is still sufficient to support successful transmission via the aggressor technology. 
     In this regard, it may not be necessary to eliminate desense energy to protect the data received via the victim technology. Instead, it can be sufficient to decrease the desense energy below an acceptable threshold, such as may determined by the applicable specification, packet type, and/or other factors, which will be discussed further herein. Further, the presence of adjacent band energy is due largely to second order nonlinearities in the aggressor technology transmit chain. Thus, when the aggressor transmission power is reduced by some amount, the unwanted adjacent band power can reduced by a significantly larger amount (due to the nonlinear relationship). As such, a relatively modest reduction in aggressor technology transmission power can enable successful reception via the victim technology by preventing victim technology desense that can be caused by blocker interference and OOB interference. 
     In some example embodiments, the transmission power of the aggressor transmission can be reduced to the threshold level prior to the scheduled time period during which a data reception is to occur via the victim technology. Subsequent to the time period, if transmission via the aggressor technology is still occurring, the transmission power can be increased back to a level exceeding the threshold level. As such, reception via the victim technology can proceed without being damaged by the aggressor transmission, which can also proceed as scheduled. 
       FIG. 2  illustrates an example time domain view of transmission power modulation to facilitate in-device coexistence between wireless communication technologies in accordance with some example embodiments. In this regard,  FIG. 2  illustrates an example application of some example embodiments to the example scenario illustrated in  FIG. 1 . As illustrated in  FIG. 2 , a threshold level  202  is defined that is less than the full transmission power of the aggressor technology. The threshold level  202  can be any transmission power level at which aggressor transmissions do not inhibit concurrent data reception via the victim technology, but that is still sufficient to support successful transmission via the aggressor technology. 
     The transmission power of the aggressor transmission  204  can be reduced to the threshold level  202  prior to time t 1  when the reception  206  via the victim technology is scheduled to begin. It will be appreciated that the illustration in  FIG. 2  is provided by way of example, and not by way of limitation. In this regard, there is no limit to how far in advance of t 1  that the transmission power is reduced to the threshold level  202  or the rate at which the transmission power is reduced. Accordingly, it will be appreciated that the rate and timing of power modulation can vary in different implementations so long as the transmission power is reduced to the threshold level  202  in advance of t 1 . 
     The transmission power of the aggressor transmission  204  can be controlled during the reception  206  such that it does not exceed the threshold level  202 . In this regard, the transmission power during the reception  206  can, for example, be controlled such that the transmission power remains substantially constant at threshold level  202 . Alternatively, the transmission power can vary during the reception  206 , but can be constrained so that it does not exceed threshold level. As the transmission  204  concludes prior to time t 1  when the reception  206  concludes, the transmission power of the aggressor transmission  204  can be controlled to not exceed the threshold level  202  from prior to time t 1  until conclusion of the aggressor transmission  204 . 
     As the aggressor transmission  208  coincides with the data reception  210 , the transmission power of the transmission  208  can be reduced to the threshold level  202  prior to time t 3  when the reception  210  via the victim technology is scheduled to begin. The transmission power of the aggressor transmission  204  can be controlled during the reception  210  such that it does not exceed the threshold level  202 . As the aggressor transmission  208  continues following time t 4  when the reception  210  concludes, the transmission power of the transmission  208  can be increased to a level exceeding the threshold level  202  following t 4 . The transmission power can, for example, be increased to the same level as was used prior to the transmission power being reduced in advance of t 3 . However, it will be appreciated that in instances in which the transmission power of a transmission  208  is increased subsequent to t 3 , it can be increased to any level, including a level different from that used prior to the transmission power being reduced in advance of t 3 . It will be further appreciated that at the illustration in  FIG. 2  is provided by way of example, and not by way of limitation. As such, it will be noted that the timing and rate of the increase in transmission power following t 4  can vary in different implementations. 
     Aggressor transmission  212  does not coincide with a victim technology reception period. As such, a transmission power exceeding threshold level  202  can be used for the duration of aggressor transmission  212 . 
       FIG. 3  illustrates an example transmission power waveform in accordance with some example embodiments. In this regard,  FIG. 3  illustrates an example modulation of transmission power of an aggressor transmission in response to an overlapping reception period for a victim technology in accordance with some example embodiments. For example, the transmission power waveform of  FIG. 3  can be applied to the transmission power of aggressor transmission  208  illustrated in  FIG. 2 . 
     As illustrated in  FIG. 3 , the transmission power can be reduced from an unmodulated power level  302  to a threshold power level  304  in advance of time t 1 , which can coincide with the start of a reception period for a victim technology. It will be appreciated that the illustration in  FIG. 3  is provided by way of example, and not by way of limitation. In this regard, there is no limit to how far in advance of t 1  that the transmission power is reduced to the threshold power level  304  or the rate at which the transmission power is reduced. Accordingly, it will be appreciated that the rate and timing of power modulation can vary in different implementations so long as the transmission power is reduced to the threshold level  304  in advance of t 1 . After reduction to the threshold power level  304 , the transmission power can be controlled such that it does not exceed the threshold power level  304  until after time t 2 , which can coincide with the conclusion of the reception period for the victim technology. After t 2 , the transmission power can be increased to a level exceeding the threshold power level  304 , and can, for example, be returned to the unmodulated power level  302 . It will be appreciated that the timing, rate, and level of transmission power increase illustrate din  FIG. 3  following t 2  is illustrated by way of example, and not by way of limitation. 
     Some example embodiments provide for increasing power amplifier linearity in addition to or in alternative to transmission power modulation in order to facilitate in-device coexistence between wireless communication technologies. In this regard, such example embodiments provide for adjusting an operational parameter of a power amplifier applied to a transmission emitted via an aggressor technology to increase a linearity of the power amplifier during a scheduled time period in which data is received by a victim technology. For example, some such example embodiments provide for adjusting a bias current applied to the power amplifier in order to increase linearity. By increasing linearity of a power amplifier during a victim technology reception period, victim technology desense that can be caused by OOB interference and harmonics interference can be prevented. 
     Having now introduced aspects of various embodiments, several embodiments will now be described in more detail. Referring now to  FIG. 4 ,  FIG. 4  illustrates a block diagram of a mobile communication device  400  in accordance with some example embodiments. The mobile communication device  400  can be any device capable of communicating via multiple wireless communication technologies. By way of non-limiting example, the mobile communication device  400  can be a mobile phone, tablet computing device, laptop computer, or other computing device adapted to communicate via multiple wireless communication technologies. It will be appreciated that the components, devices or elements illustrated in and described with respect to  FIG. 4  below may not be mandatory and thus some may be omitted in certain embodiments. Additionally, some embodiments can include further or different components, devices or elements beyond those illustrated in and described with respect to  FIG. 4 . 
     In some example embodiments, the mobile communication device  400  can include processing circuitry  410  that is configurable to perform actions in accordance with one or more example embodiments disclosed herein. In this regard, the processing circuitry  410  can be configured to perform and/or control performance of one or more functionalities of the mobile communication device  400  in accordance with various example embodiments, and thus can provide means for performing functionalities of the mobile communication device  400  in accordance with various example embodiments. The processing circuitry  410  may be configured to perform data processing, application execution and/or other processing and management services according to one or more example embodiments. In some embodiments, the mobile communication device  400  or a portion(s) or component(s) thereof, such as the processing circuitry  410 , can include one or more chips, or one or more chipsets. The processing circuitry  410  and/or one or more further components of the mobile communication device  400  can therefore, in some instances, be configured to implement an embodiment on a single chip or chipset. 
     In some example embodiments, the processing circuitry  410  can include a processor  412  and, in some embodiments, such as that illustrated in  FIG. 2 , can further include memory  414 . The processing circuitry  410  can be in communication with or otherwise control an aggressor technology transceiver  416 , victim technology transceiver  418 , aggressor technology control module  420 , and/or victim technology control module  422 . 
     The processor  412  can be embodied in a variety of forms. For example, the processor  412  can be embodied as various processing means such as a microprocessor, a coprocessor, a controller or various other computing or processing devices including integrated circuits such as, for example, an ASIC (application specific integrated circuit), an FPGA (field programmable gate array), some combination thereof, or the like. Although illustrated as a single processor, it will be appreciated that the processor  412  can comprise a plurality of processors. The plurality of processors can be in operative communication with each other and can be collectively configured to perform one or more functionalities of the mobile communication device  400  as described herein. In some example embodiments, the processor  412  can be configured to execute instructions that can be stored in the memory  414  or that can be otherwise accessible to the processor  412 . As such, whether configured by hardware or by a combination of hardware and software, the processor  412  capable of performing operations according to various embodiments while configured accordingly. 
     In some example embodiments, the memory  414  can include one or more memory devices. Memory  414  can include fixed and/or removable memory devices. In some embodiments, the memory  414  can provide a non-transitory computer-readable storage medium that can store computer program instructions that can be executed by the processor  412 . In this regard, the memory  414  can be configured to store information, data, applications, instructions and/or the like for enabling the mobile communication device  400  to carry out various functions in accordance with one or more example embodiments. In some embodiments, the memory  414  can be in communication with one or more of the processor  412 , aggressor technology transceiver  416 , victim technology transceiver  418 , aggressor technology control module  420 , or victim technology control module  422  via a bus(es) for passing information among components of the mobile communication device  400 . 
     The mobile communication device  400  can further include a plurality of transceivers. Each such transceiver can be configured to enable the mobile communication device  400  to communicate via a particular wireless communication technology. In the example of  FIG. 4 , an aggressor technology transceiver  416  and victim technology transceiver  418  are illustrated. The aggressor technology transceiver  416  and victim technology transceiver  418  can each support any wireless communication technology. Transmissions via an aggressor technology supported by the aggressor technology transceiver  416  at a power level exceeding a threshold level defined in accordance with various embodiments that overlap with data reception via a victim technology supported by the victim technology transceiver  418  can impact the data reception via the victim technology. In some example embodiments, the aggressor technology transceiver  416  can be a cellular transceiver. For example, the aggressor technology transceiver  416  can be configured to support communication via a Long Term Evolution (LTE) cellular communication technology, a Universal Mobile Telecommunications System (UMTS) cellular communication technology, a Global System for Mobile Communications (GSM) cellular communication technology, a Code Division Multiple Access (CDMA) cellular communication technology, or a CDMA 2000 cellular communication technology, and/or the like. In some example embodiments, the victim technology transceiver can be a transceiver supporting a communications technology using an ISM band, such as Bluetooth, Zigbee, or other wireless personal area network (PAN) technology; Wi-Fi or other wireless local area network (LAN) communication technology; or other wireless communication technology using an ISM band. It will be appreciated, however, that embodiments are not limited to facilitating cellular and ISM band coexistence, as some embodiments can facilitate in-device coexistence between any two disparate wireless communication technologies. For example, in some embodiments, the aggressor technology transceiver  416  can support a first cellular communication technology and the victim technology transceiver  418  can support a second cellular communication technology. As a further alternative example, in some embodiments, the aggressor technology transceiver  416  can support a first wireless communication technology using an ISM band and the victim technology transceiver  416  can support a second wireless communication technology using an ISM band. 
     The mobile communication device  400  can further include aggressor technology control module  420 , which can be configured to interface with and/or otherwise control operation of the aggressor technology transceiver  416 . The aggressor technology control module  420  can be embodied as various means, such as circuitry, hardware, a computer program product comprising computer readable program instructions stored on a computer readable medium (for example, the memory  414 ) and executed by a processing device (for example, the processor  412 ), or some combination thereof. In some embodiments, the processor  412  (or the processing circuitry  410 ) can include, or otherwise control the aggressor technology control module  420 . 
     The mobile communication device  400  can additionally include victim technology control module  422 , which can be configured to interface with and/or otherwise control operation of the victim technology transceiver  418 . The victim technology control module  422  can be embodied as various means, such as circuitry, hardware, a computer program product comprising computer readable program instructions stored on a computer readable medium (for example, the memory  414 ) and executed by a processing device (for example, the processor  412 ), or some combination thereof. In some embodiments, the processor  412  (or the processing circuitry  410 ) can include, or otherwise control the victim technology control module  422 . 
     In some example embodiments, the aggressor technology control module  420  and victim technology control module  422  can be configured to communicate with each other via an interface  424 . In this regard, the interface  424  can enable the victim technology control module  422  to send a message to the aggressor technology control module that can include an indication of a scheduled time period during which data is received by the victim technology transceiver  418  so that the aggressor technology control module  420  can reduce a transmission power of a transmission via the aggressor technology transceiver  416  and/or increase a linearity of a power amplifier(s) applied to the transmission such that the transmission does not inhibit data reception by the victim technology transceiver  418 . In some example embodiments, the interface  424  can be a direct interface between the aggressor technology control module  420  and victim technology control module  422 . However, it will be appreciated that embodiments are not so limited. In this regard, the interface  424  can be an interface having a route through one or ore other modules or components of the mobile communication device  400  (potentially including one or more modules or components that are not illustrated in  FIG. 4 ). For example, the interface  424  can interface the aggressor technology control module  420  and victim technology control module  422  indirectly via the processing circuitry  410 . In some example embodiments in which the victim technology is Bluetooth, the interface  424  can be implemented as a Wireless Coexistence Interface 2 (WCI-2) interface, which can be extended in accordance with one or more embodiments to support a message from the victim technology control module  422  to the aggressor technology control module  420  including an indication of a time period during which data is received via the victim technology. 
     As discussed, in some example embodiments, the components illustrated in  FIG. 4  can form one or more chipsets.  FIG. 5  illustrates interfaced chipsets configured to facilitate in-device coexistence between wireless communication technologies in accordance with some such example embodiments. In the example of  FIG. 5 , an aggressor technology chipset  502  can include aggressor technology transceiver  504 , aggressor technology control module  506 , and interface component  508 . Aggressor technology transceiver  504  can, for example, be an embodiment of aggressor technology transceiver  416 . Aggressor technology control module  506  can, for example, be an embodiment of aggressor technology control module  420 . The interface component  508  can enable coupling of the aggressor technology chipset  502  to the victim technology chipset  512  via interface  520  between the aggressor technology chipset  502  and the victim technology chipset  512 . The interface  520  can, for example, be an embodiment of the interface  424 . The aggressor technology chipset  502  can be a chipset configured to support communication via a particular wireless communication technology, which can be implemented on, or otherwise operably coupled to a computing device, such as the mobile communication device  400 , to enable the computing device to engage in wireless communications via the wireless communication technology supported by the aggressor technology chipset  502 . Thus, for example, in embodiments in which the aggressor technology chipset  502  comprises a cellular chipset, the aggressor technology chipset  502  can enable a device to engage in cellular communications when implemented on the device. 
     The victim technology chipset  512  can include victim technology transceiver  514 , victim technology control module  516 , and interface component  518 . Victim technology transceiver  514  can, for example, be an embodiment of victim technology transceiver  418 . Victim technology control module  516  can, for example, be an embodiment of victim technology control module  422 . The interface component  518  can enable coupling of the victim technology chipset  512  to the aggressor technology chipset  502  via interface  520 . The victim technology chipset  512  can be a chipset configured to support communication via a particular wireless communication technology, which can be implemented on, or otherwise operably coupled to a computing device, such as the mobile communication device  400 , to enable the computing device to engage in wireless communications via the wireless communication technology supported by the victim technology chipset  512 . Thus, for example, in embodiments in which the victim technology chipset  512  comprises a Bluetooth chipset, the aggressor technology chipset  512  can enable a device to engage in Bluetooth communications when implemented on the device. 
     It will be appreciated that embodiments other than those in separate chipsets are used for the aggressor technology and the victim technology are contemplated within the scope of the disclosure. For example, in some example embodiments, both the aggressor technology and the victim technology can be supported by the same chip or chipset. In such embodiments, the both the aggressor technology control module  420  and victim technology control module  422  can be co-located on a single chip or chipset. Thus, for example, some example embodiments can be implemented on a single chip or chipset configured to provide both cellular and Bluetooth communication functionality. 
       FIG. 6  illustrates an example system  600  in which some example embodiments can be implemented to facilitate in-device coexistence between wireless communication technologies. The system  600  can include a mobile communication device  602 , which can, for example, be an embodiment of mobile communication device  402 . In some example embodiments, the mobile communication device  602  can include aggressor technology chipset  502  and victim technology chipset  512 . The mobile communication device  602  can be configured to engage in cellular communications, which can be supported by a base transceiver station  604 . For example, the mobile communication device  602  can be configured to engage in communication via a Long Term Evolution (LTE) cellular communication technology, a Universal Mobile Telecommunications System (UMTS) cellular communication technology, a Global System for Mobile Communications (GSM) cellular communication technology, a Code Division Multiple Access (CDMA) cellular communication technology, or a CDMA 2000 cellular communication technology, and/or other cellular communication technology. The mobile communication device  602  can be further configured to engage in communications via an ISM band technology. Thus, for example, the mobile communication device  602  can engage in wireless communications with a device  608  via an ISM band network  606 . For example, in embodiments in which the ISM band network  606  is a Bluetooth network, the device  608  can be a Bluetooth headset or other Bluetooth device that can be interfaced with a mobile communication device. 
     In context of the system  600 , various embodiments, including at least some of those described further herein below can be implemented on the mobile communication device  602  to control the transmission power of cellular transmissions sent by the mobile communication device  602  to the base transceiver station  604  during periods in which the mobile communication device  602  is scheduled to receive data sent by the device  608  via the ISM band network  606  so that data receipt via the ISM band technology is not impacted by the cellular transmissions. Additionally or alternatively, at least some embodiments described herein below can be implemented on the mobile communication device  602  to increase linearity of a power amplifier(s) applied to a cellular transmission sent by the mobile communication device  602  to the base transceiver station  604  during periods in which the mobile communication device  602  is scheduled to receive data sent by the device  608  via the ISM band network  606  so that data receipt via the ISM band technology is not impacted by the cellular transmissions. It will be appreciated, however, that system  600  is provided merely by way of example. In this regard, as previously noted, some example embodiments facilitate in-device wireless communication technology coexistence scenarios other than cellular and ISM band coexistence. 
     Having now described example devices and components that can implement various embodiments disclosed herein and an example system in which some example embodiments can be implemented, several example embodiments will be described in additional detail with reference to the components described in  FIGS. 4 and 5 . Further, some example embodiments will be described by way of example with respect to the system  600  illustrated in  FIG. 6 . 
     The victim technology control module  422  of some example embodiments can be configured to determine one or more scheduled time periods during which data is received via the victim technology and for which action should be taken to reduce interference from transmissions via the aggressor technology. In this regard, for example, the victim technology control module  422  of some such example embodiments can be configured to determine one or more scheduled time periods during which data is received via the victim technology and for which a transmission power associated with a transmission via the aggressor technology should be reduced. Additionally or alternatively, the victim technology control module  422  of some such example embodiments can be configured to determine one or more scheduled time periods during which data is received via the victim technology and for which linearity of a power amplifier(s) that can be applied to a transmission via the aggressor technology should be increased. The scheduled time periods can be dedicated time slots or other periods during which data is scheduled to be received via the victim technology. The scheduled time periods can, for example, be negotiated between the mobile communication device  400  and another device with which the mobile communication device  400  can be communicating via the victim technology, such as by way of non-limiting example, the device  608 . In some embodiments, communication via the victim technology can include communication over a synchronous connection using synchronized scheduled time slots. For example, in embodiments in which the victim technology is Bluetooth, communication can be over a synchronous connection oriented (SCO) link or an enhanced SCO (eSCO) link having a set of reserved timeslots scheduled for data reception. Accordingly, the victim technology control module  422  can be configured to determine a scheduled time slot during which data is received via the victim technology based on a known schedule that can be established upon link setup, negotiated with another device, and/or the like. 
     The victim technology control module  422  can be further configured to format a message including an indication of a scheduled time period(s) during which data is received via the victim technology. In this regard, the message can indicate a period(s) for which a transmission power associated with a transmission via the aggressor technology should be reduced and/or for which a linearity of a power amplifier(s) that can be applied to a transmission via the aggressor technology should be increased. The indication of a scheduled time period can be any information that can enable the aggressor technology control module  420  to identify a starting time and an ending time of a victim technology reception period. By way of non-limiting example, the indication can include a start time, an offset from a present time indicating when a reception period is to begin, an end time of the reception period, a duration of a reception period, a time slot identifier, and/or other information to enable the aggressor technology control module  420  to identify a time period indicated in the message. The victim technology control module  422  can be further configured to send the message to the aggressor technology control module  420  via the interface  424 . In this regard, the message can be sent to request that the aggressor technology control module  420  reduce the transmission power to the threshold level prior to the scheduled time period(s) and control the transmission power so that it does not exceed the threshold level during the scheduled time period(s). Additionally or alternatively, the message can be sent to request that the aggressor technology control module  422  increase a linearity of a power amplifier(s) that can be applied to an aggressor technology transmission during the scheduled time period(s). 
     In some example embodiments, a message may only contain an indication of a single scheduled time period. In this regard, in such example embodiments, a message can, for example, be formatted and sent by the victim technology control module  422  in advance of each scheduled time period for which the aggressor technology transmission power needs to be reduced and/or for which power amplifier linearity needs to be increased. Additionally or alternatively, in some example embodiments, the victim technology control module  422  can format and send a message including an indication of a plurality of scheduled time periods for which the aggressor technology transmission power needs to be reduced and/or for which power amplifier linearity needs to be increased. In this regard, the victim technology control module  422  may be aware in advance of a plurality of scheduled time periods during which data is received and for which the aggressor technology transmission power needs to be reduced and/or for which power amplifier linearity needs to be increased, and can format and send a single message to the aggressor technology control module  420  that indicates each of the plurality of scheduled time periods. Accordingly, processing and signaling overhead can be reduced in such embodiments by using a single message to notify the aggressor technology control module  420  of multiple scheduled time periods. As an example, in some instances, a schedule can be negotiated or assigned during setup of a communication link using the victim technology. In such instances, the victim technology control module  422  can send a message notifying the aggressor technology control module  420  of known scheduled time periods during which data is received via the victim technology and for which the victim technology transmission power should be reduced and/or for which power amplifier linearity should be increased during or following setup of the victim technology communication link on the basis of the known schedule. 
     The aggressor technology control module  420  can be configured to receive a message sent by the victim technology control module  422  via the interface  424 . The aggressor technology control module  420  can be further configured to determine a scheduled time period(s) during which data is received via the victim technology on the basis of indication(s) included in a received message. In response to the message, the aggressor technology control module  420  can reduce the transmission power of an aggressor technology transmission that may be emitted by the aggressor technology transceiver to a threshold level prior to a scheduled time period indicated in the message and control the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level. If transmission via the aggressor technology is still ongoing following conclusion of the scheduled time period, the aggressor technology control module  420  can be further configured to increase the transmission power to a level exceeding the threshold level subsequent to the scheduled time period. 
     The reduction and control of the transmission power to enable receipt of data via the victim technology during a scheduled time period can, for example, be performed in a manner similar to that illustrated in and described with respect to  FIGS. 2 and 3 . In some example embodiments, such as that illustrated in  FIG. 6  in which the aggressor technology is a cellular technology, the reduction and control of the transmission power can, for example, take into account a power control loop configuration of the base transceiver station  604 . 
     The threshold level to which transmission power is reduced can be implementation specific on the basis of the implementation of the mobile communication device  400 . In this regard, the threshold level may vary on the basis of filters that may be used for the victim technology and/or for the aggressor technology, a proximity and arrangement of the aggressor technology transceiver  416  and victim technology transceiver  418 . In some example embodiments, the threshold level can vary on the basis of actual channel conditions, such as particular channel assignments, packet types, use profile, use case etc, and/or the like. Accordingly, variety of factors can be considered in order to determine the threshold level that is appropriate to a particular device implementation and channel scenario. In some example embodiments, such as those in which the threshold level is dependent solely upon channel implementation, the threshold level can be set and provisioned by a device manufacturer, network service provider, or the like. In embodiments in which a threshold level can vary on the basis of channel conditions, the aggressor technology control module and/or victim technology control module  422  can be configured to calculate the threshold level on the basis of existing channel conditions. Such calculation can additionally take into account a design implementation of the mobile communication device  400 , such as filters that may be used for the victim technology and/or for the aggressor technology, a proximity and arrangement of the aggressor technology transceiver  416  and victim technology transceiver  418 , and/or other deign factors that can influence the threshold level. 
     As such, it will be appreciated that the actual threshold level can vary with implementation and, in some embodiments, can vary on the basis of experienced channel conditions, link configuration, and/or the like. However, regardless of the particular implementation, the threshold level can be a power level at which transmission via the aggressor technology does not inhibit concurrent data reception via the victim technology. 
     The aggressor technology control module  420  can be configured to use any of a variety of methods to control the transmission power. By way of example, in some embodiments, a lookup table may store one or more transmission power curves specifying a power modulation curve for a particular time period duration. The aggressor technology control module  420  can accordingly be configured in such embodiments to look up an appropriate modulation curve for a given time period during which data is received via the victim technology and can apply the modulation curve. Additionally or alternatively, in some example embodiments, a low pass filter can be used to reduce the transmission power. As a further example, in some embodiments, the aggressor technology control module  420  can use a series of commands to step down transmission power and, if transmission power is increased subsequent to conclusion of a victim reception time period, to step up the transmission power. As yet another example, the aggressor technology control module  420  of some embodiments can be configured to utilize a response time of a digitally controlled power supply to control the transmission power. 
     In some example embodiments, transmission power of the aggressor technology can be reduced each time period during which data is received via the victim technology. Alternatively, in some example embodiments, transmission power can be selectively reduced such that transmission power is not reduced for each reception period during which data is received via the victim technology. In such embodiments, the victim technology control module  422  can selectively determine for a scheduled time period in which data is received via the victim technology whether the transmission power should be reduced. If the victim technology control module  422  determines that transmission power should not be reduced for the scheduled time period, the victim technology control module  422  can determine to not send a message to the aggressor technology control module  420  that includes an indication of the scheduled time period. 
     As an example of selective reduction of transmission power for a subset of scheduled time periods in which data is received via the victim technology, the victim technology control module  422  can be configured in some example embodiments to determine whether data to be received satisfies a threshold priority criterion. If the data received in a particular time period does not satisfy the threshold priority criterion, then the victim technology control module  422  can determine that the transmission power should not be reduced for that time period. For example, in some example embodiments, control messages, such as messages relating to connection configuration or link management, can be prioritized over other non-control messages. Accordingly, in such embodiments, if the victim technology control module  422  determines that a control message is received in a time period, the victim technology control module  422  can determine that transmission power of the aggressor technology should be reduced for that time period. However, if data received in a time period is a non-control message (e.g., a simple data message), the victim technology control module  422  may determine that the non-control message does not satisfy a threshold priority criterion and that transmission power of the aggressor technology should not be reduced for that time period. Control messages can, for example, provide for connection control, including, by way of non-limiting example, connection establishment, connection detachment, time slot configuration, power control, adaptive frequency hopping, channel quality driven data rate change (CQDDR), quality of service control, data rate control, role switching, and/or the like. As a further example, control messages can provide for security measures, such as, by way of non-limiting example, authentication, pairing, link key establishment, encryption configuration, and/or the like. In embodiments in which the victim technology is Bluetooth, a control message can include Link Manger Protocol (LMP) messages. If an LMP message is received in a time period, then transmission power of an aggressor technology transmission can be reduced. However, transmission power may not be reduced for reception of data other than LMP messages. 
       FIG. 7  illustrates a flowchart according to an example method for performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  710  can include determining a scheduled time period during which data is received via a first wireless communication technology. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , victim technology control module  422 , aggressor technology chipset  502 , and victim technology chipset  512  can, for example, provide means for performing operation  710 . Operation  720  can include reducing a transmission power of a transmission via a second wireless communication technology to a threshold level prior to the scheduled time period. Operation  730  can include controlling the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level. Operation  740  can include, subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology transceiver  416 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operations  720 - 740 . 
       FIG. 8  illustrates a flowchart according to another example method for performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  810  can include receiving, via an interface (e.g., interface  424 ), a message sent by a control module for a first wireless communication technology that includes an indication of a scheduled time period during which data is received via the first wireless communication technology. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operation  810 . Operation  820  can include, in response to the message, reducing a transmission power of a transmission via a second wireless communication technology to a threshold level prior to the scheduled time period. Operation  830  can include controlling the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level. Operation  840  can include, subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology transceiver  416 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operations  820 - 840 . 
       FIG. 9  illustrates a flowchart according to an example method for enabling performance of transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  910  can include determining a scheduled time period during which data is received via a first wireless communication technology. Operation  920  can include determining that transmission power of a transmission via a second wireless communication technology should be reduced to a threshold level during the scheduled time period. Operation  930  can include sending a message (e.g., via interface  424 ) including an indication of the time period to a control module for the second wireless communication technology (e.g., aggressor technology control module  420  or aggressor technology chipset  502 ) so that the control module can reduce the transmission power to the threshold level prior to the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , victim technology control module  422 , and victim technology chipset  512  can, for example, provide means for performing operations  910 - 930 . 
       FIG. 10  illustrates a flowchart according to a further example method for performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  1010  can include determining a scheduled time period during which data is received via a first wireless communication technology. Operation  1020  can include determining whether data to be received satisfies a threshold priority criterion. One or more of processing circuitry  410 , processor  412 , memory  414 , victim technology control module  422 , and victim technology chipset  512  can, for example, provide means for performing operations  1010 - 1020 . 
     In an instance in which it is determined at operation  1020  that the data to be received does satisfy a threshold priority criterion, the method can further include one or more of operations  1030 - 1050 . Operation  1030  can include reducing a transmission power of a transmission via a second wireless communication technology to a threshold level prior to the scheduled time period. Operation  1040  can include controlling the transmission power during the scheduled time period so that the transmission power does not exceed the threshold level. Operation  1050  can include, subsequent to the scheduled time period, increasing the transmission power to a level exceeding the threshold level. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology transceiver  416 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operations  1030 - 1050 . 
     If, however, it is determined at operation  1020  that the data to be received does not satisfy a threshold priority criterion, the method can further include operation  1060 . Operation  1060  can include determining to not reduce transmission power during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , victim technology control module  422 , and victim technology chipset  512  can, for example, provide means for performing operation  1060 . 
     In some example embodiments, the aggressor technology control module  420  can be configured to adjust an operational parameter of a power amplifier(s) applied to an aggressor technology transmission to increase a linearity of the power amplifier(s) during a scheduled time period indicated in a message sent by the victim technology control module  422 . In such example embodiments, power amplifier linearity can be increased in addition to or in lieu of performance of transmission power modulation. Adjustment of the operational parameter of a power amplifier can, for example, include adjusting a bias current that can be applied to a power amplifier in order to increase the linearity of the power amplifier. 
       FIG. 11  illustrates examples of current biasing to achieve increased linearity of a power amplifier according to some example embodiments. In this regard,  FIG. 11  illustrates a graph output signal versus input signal of an example power amplifier for four example bias currents ranging from a lowest relative bias current  1108  to a highest relative bias current  1114 . For each given bias current, a power amplifier can operate in three given ranges  1102 - 1106 . The range  1102  is a linear range in which a relatively low input signal is applied to the power amplifier. Power consumption in the range  1102  can be relatively high, but OOB interference to the victim technology can be relatively low. The range  1104  can be a non-linear range, which can offer relatively low power consumption, but at the expense of relatively high OOB interference to the victim technology. Range  1106  can be a non-operational range for the example power amplifier. Thus, power amplifier linearity can be increased with application of a higher bias current, but at the expense of greater power consumption. 
     During periods in which data is not being received via the victim technology in situations in which a target transmission power operating point is to be achieved, the example power amplifier of  FIG. 11  can be operated so as to reduce power consumption. In this regard, a bias current as low as possible to meet the target transmission power operating point can be used. For example, the power amplifier can be operated in the range  1104  using the bias current  1110  during such periods. 
     In some example embodiments, bias current can be increased during a scheduled time period in which data is received via the victim technology to achieve increased power amplifier linearity. In this regard, an OOB emission mask and/or harmonic energy constraints can be met by reducing the bias current to increase power amplifier linearity. With reference to  FIG. 11 , a power amplifier can be operated in the range  1102  using the bias current  1112  or bias current  1114  during a scheduled period in which data is received via the victim technology, even at the expense of higher power consumption. 
     In some example embodiments, adjustment of a bias current can be performed in accordance with a power consumption constraint. Thus, for example, a bias current may not be increased to a highest level due to a power consumption constraint that can limit a bias current level to avoid excessive power consumption. As an example, the bias current  1112  can be used rather than the bias current  1114  even though greater linearity can be achieved using the bias current  1114  in situations in which usage of the bias current  1114  would exceed a power consumption constraint. In some such example embodiments, a power amplifier can also be operated to ensure that a regulatory emissions mask is met. Further, in some such example embodiments, a power amplifier can be operated to comply with constraints, such as OOB emissions constraints, that can be imposed by a regulatory body, such as the Federal Communications Commission (FCC). 
     In some example embodiments, multiple power amplifiers, such as a chain of power amplifiers can be applied to an aggressor technology transmission. In such example embodiments, an operational parameter of each of a plurality of power amplifiers can be adjusted to achieve increased linearity of multiple power amplifiers during a scheduled period in which data is received via the victim technology. 
     In some example embodiments, an operational parameter of a power amplifier can be adjusted from an initial state, such as a default state, at a point prior to a scheduled time period. Following the scheduled time period, the operational parameter can be returned to the initial state. Thus, using the example of  FIG. 11 , the bias current can be increased from the bias current  1110  to the bias current  1112  or bias current  1114  prior to, or at the start of, a scheduled time period in which data is received via the victim technology, and can be returned to the bias current  1110  at, or following, conclusion of the scheduled time period. 
     In some example embodiments, power amplifier linearity can be increased each time period during which data is received via the victim technology. Alternatively, in some example embodiments, power amplifier linearity can be selectively increased such that power amplifier is not increased for each reception period during which data is received via the victim technology. In such embodiments, the victim technology control module  422  can selectively determine for a scheduled time period in which data is received via the victim technology whether the power amplifier linearity should be increased. If the victim technology control module  422  determines that power amplifier linearity should not be increased for the scheduled time period, the victim technology control module  422  can determine to not send a message to the aggressor technology control module  420  that includes an indication of the scheduled time period. 
     As an example of selective increase of power amplifier linearity for a subset of scheduled time periods in which data is received via the victim technology, the victim technology control module  422  can be configured in some example embodiments to determine whether data to be received satisfies a threshold priority criterion. If the data received in a particular time period does not satisfy the threshold priority criterion, then the victim technology control module  422  can determine that power amplifier linearity should not be increased for that time period. For example, in some example embodiments, control messages, such as messages relating to connection configuration or link management, can be prioritized over other non-control messages. Accordingly, in such embodiments, if the victim technology control module  422  determines that a control message is received in a time period, the victim technology control module  422  can determine that power amplifier linearity should be increased for that time period. However, if data received in a time period is a non-control message (e.g., a simple data message), the victim technology control module  422  may determine that the non-control message does not satisfy a threshold priority criterion and that power amplifier linearity should not be increased for that time period. Control messages can, for example, provide for connection control, including, by way of non-limiting example, connection establishment, connection detachment, time slot configuration, power control, adaptive frequency hopping, channel quality driven data rate change (CQDDR), quality of service control, data rate control, role switching, and/or the like. As a further example, control messages can provide for security measures, such as, by way of non-limiting example, authentication, pairing, link key establishment, encryption configuration, and/or the like. In embodiments in which the victim technology is Bluetooth, a control message can include Link Manger Protocol (LMP) messages. If an LMP message is received in a time period, then power amplifier linearity can be increased. However, power amplifier linearity may not be increased for reception of data other than LMP messages. 
       FIG. 12  illustrates a flowchart according to an example method for increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  1210  can include determining a scheduled time period during which data is received via a first wireless communication technology. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , victim technology control module  422 , aggressor technology chipset  502 , and victim technology chipset  512  can, for example, provide means for performing operation  1210 . Operation  1220  can include adjusting an operational parameter of a power amplifier applied to a transmission via a second wireless communication technology to increase a linearity of the power amplifier during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , aggressor technology chipset  502  can, for example, provide means for performing operation  1220 . 
       FIG. 13  illustrates a flowchart according to another example method for increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  1310  can include receiving, via an interface (e.g., interface  424 ), a message sent by a control module for a first wireless communication technology that includes an indication of a scheduled time period during which data is received via the first wireless communication technology. Operation  1320  can include, in response to the message, adjusting an operational parameter of a power amplifier applied to a transmission via a second wireless communication technology to increase a linearity of the power amplifier during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operations  1310 - 1320 . 
       FIG. 14  illustrates a flowchart according to an example method for enabling increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  1410  can include determining a scheduled time period during which data is received via a first wireless communication technology. Operation  1420  can include determining that a linearity of a power amplifier applied to a transmission from the device via a second wireless communication technology should be increased during the scheduled time period. Operation  1430  can include sending a message (e.g., via interface  424 ) including an indication of the time period to a control module for the second wireless communication technology (e.g., aggressor technology control module  420  or aggressor technology chipset  502 ) so that the control module can increase the linearity of the power amplifier during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , victim technology control module  422 , and victim technology chipset  512  can, for example, provide means for performing operations  1410 - 1430 . 
       FIG. 15  illustrates a flowchart according to a further example method for increasing linearity of a power amplifier to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  1510  can include determining a scheduled time period during which data is received via a first wireless communication technology. Operation  1520  can include determining whether data to be received satisfies a threshold priority criterion. One or more of processing circuitry  410 , processor  412 , memory  414 , victim technology control module  422 , and victim technology chipset  512  can, for example, provide means for performing operations  1510 - 1520 . 
     In an instance in which it is determined at operation  1520  that the data to be received does satisfy a threshold priority criterion, the method can proceed to operation  1530 , which can include adjusting an operational parameter of a power amplifier applied to a transmission via a second wireless communication technology to increase a linearity of the power amplifier during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology transceiver  416 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operation  1530 . If, however, it is determined at operation  1520  that the data to be received does not satisfy the threshold priority criterion, the method can proceed to operation  1540 , in which the linearity of the power amplifier is not increased during the scheduled time period. 
       FIG. 16  illustrates a flowchart according to an example method for increasing linearity of a power amplifier and performing transmission power modulation to facilitate in-device coexistence between wireless communication technologies according to some example embodiments. Operation  1610  can include determining a scheduled time period during which data is received via a first wireless communication technology. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , victim technology control module  422 , aggressor technology chipset  502 , and victim technology chipset  512  can, for example, provide means for performing operation  1610 . Operation  1620  can include adjusting an operational parameter of a power amplifier applied to a transmission via a second wireless communication technology to increase a linearity of the power amplifier during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operation  1620 . Operation  1630  can include reducing a transmission power of a transmission via the second wireless communication technology so that the transmission power does not exceed a threshold level during the scheduled time period. One or more of processing circuitry  410 , processor  412 , memory  414 , aggressor technology transceiver  416 , aggressor technology control module  420 , and aggressor technology chipset  502  can, for example, provide means for performing operation  1630 . 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. Various aspects of the described embodiments can be implemented by software, hardware or a combination of hardware and software. The described embodiments can also be embodied as computer readable code on a computer readable medium for controlling manufacturing operations or as computer readable code on a computer readable medium for controlling a manufacturing line. The computer readable medium is any data storage device that can store data which can thereafter be read by a computer system. Examples of the computer readable medium include read-only memory, random-access memory, CD-ROMs, HDDs, DVDs, magnetic tape, and optical data storage devices. The computer readable medium can also be distributed over network-coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of specific embodiments are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the described embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20120926
Publication Date: 20140715
Grant Date: 20140715
Priority Date: 20120926
Inventors: BURCHILL WILLIAM S.
MAJJIGI VINAY R.
WANG XIAOWEN
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W52/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/50", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/243", "inventive": true, "first": true, "tree": "[]"}, {"code": "Y02D30/70", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W88/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W88/06", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W52/287", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W52/52", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/287", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/38", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W52/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W52/243", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W88/06", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 50339295