PATENT DOCUMENT

Publication Number: US-9241338-B2
Application Number: US-201313896202-A
Country: US
Kind Code: B2

Title: Link adaptation resumption based on CQI offset

Abstract:
Methods, apparatuses and computer readable media are described that adjust signaling messages that include channel quality metrics communicated between a mobile wireless device and a wireless access network before and/or after interruption of a connection to improve downlink performance after resumption of the connection. One or more adjusted channel quality metrics are determined and communicated to the wireless access network to compensate at least in part for an estimate of communication channel performance degradation by a network element of the wireless access network following the interruption and resumption of the connection between the mobile wireless device and the wireless access network.

Claims:
What is claimed is:  
     
       1. A method to report channel quality metrics by a mobile wireless device to a first radio access network of a first wireless network, the method comprising:
 by the mobile wireless device: 
 determining an unadjusted channel quality metric based at least in part on a downlink signal quality measured at the mobile wireless device for one or more signals received over a connection from the first radio access network; 
 detecting an actual or forthcoming interruption of the connection between the mobile wireless device and the first radio access network, during which reception of signals from and/or transmission of signals to the first radio access network are interrupted for a period of time, followed by a resumption of the connection between the mobile wireless device and the first radio access network; and 
 in response to detecting the actual or forthcoming interruption of the connection between the mobile wireless device and the first radio access network:
 determining a channel quality metric adjustment value; 
 computing an adjusted channel quality metric based at least in part on the unadjusted channel quality metric and the channel quality metric adjustment value; and 
 transmitting the adjusted channel quality metric over the connection to the first radio access network. 
 
 
     
     
       2. The method recited in  claim 1 , wherein determining the channel quality metric adjustment value comprises estimating a maximum penalty applied by a network element of the first radio access network due to interruption of the connection for the period of time to an allocation of transmission resources in a downlink direction to the mobile wireless device. 
     
     
       3. The method recited in  claim 1 , wherein the adjusted channel quality metric comprises a channel quality indicator (CQI), a rank indicator (RI), or both. 
     
     
       4. The method recited in  claim 1 , wherein determining the channel quality metric adjustment value comprises calculating the channel quality metric adjustment value based on an estimated downlink block error rate of approximately 100 percent incurred during the period of time of the interruption of the connection. 
     
     
       5. The method recited in  claim 1 , wherein determining the unadjusted channel quality metric comprises calculating one or more channel quality metric values before detecting the interruption of the connection between the mobile wireless device and the first radio access network. 
     
     
       6. The method recited in  claim 1 , further comprising:
 by the mobile wireless device: 
 estimating a length of the period of time between a start of the interruption of the connection and a start of the resumption of the connection between the mobile wireless device and the first radio access network; 
 determining a number of times to transmit the adjusted channel quality metric to the first radio access network based on the estimated length of the period of time; and 
 wherein transmitting the adjusted channel quality metric to the first radio access network comprises transmitting the adjusted channel quality metric repeatedly for at least the determined number of times over the connection to the first radio access network. 
 
     
     
       7. The method recited in  claim 1 , wherein the mobile wireless device determines the channel quality metric adjustment value based at least in part on a particular wireless communication protocol used for the connection between the mobile wireless device and the first radio access network of the first wireless network, the first wireless network operating in accordance with the particular wireless communication protocol. 
     
     
       8. The method recited in  claim 1 , wherein the unadjusted channel quality metric comprises a maximum CQI value and a particular rank indicator (RI) value less than a maximum RI value, and wherein the adjusted channel quality metric comprises a CQI value and an adjusted RI value greater than the particular RI value. 
     
     
       9. The method recited in  claim 1 , wherein the period of time between the interruption of the connection and the resumption of the connection between the mobile wireless device and the first radio access network comprises a multi-path fade. 
     
     
       10. The method recited in  claim 1 , further comprising:
 by the mobile wireless device: 
 estimating a Doppler shift at the mobile wireless device; 
 determining a number of times to transmit the adjusted channel quality metric to the first radio access network based at least in part on the estimated Doppler shift; and 
 wherein transmitting the adjusted channel quality metric to the first radio access network comprises transmitting the adjusted channel quality metric repeatedly for at least the determined number of times over the connection to the first radio access network. 
 
     
     
       11. The method recited in  claim 1 , wherein transmitting the adjusted channel quality metric to the first radio access network comprises transmitting at least one adjusted CQI value to the first radio access network before adjusting a receiver of the mobile wireless device to receive signals from a second radio access network of a second wireless network, wherein the adjusting the receiver causes the interruption of the connection between the mobile wireless device and the first radio access network of the first wireless network. 
     
     
       12. The method recited in  claim 1 , wherein transmitting the adjusted channel quality metric to the first radio access network comprises transmitting at least one adjusted CQI value to the first radio access network after adjusting a receiver of the mobile wireless device to receive signals from a second radio access network of a second wireless network and subsequently re-adjusting the receiver of the mobile wireless device to receive signals from the first radio access network of the first wireless network. 
     
     
       13. A mobile wireless device comprising:
 one or more processors configurable to control establishing and releasing connections between the mobile wireless device and a first radio access network of a first wireless network and a second radio access network of a second wireless network; 
 a transmitter configurable to transmit signals to the first radio access network of the first wireless network in accordance with a first wireless communication protocol used by the first wireless network and to the second radio access network of the second wireless network in accordance with a second wireless communication protocol used by the second wireless network; and 
 one or more receivers configurable to receive signals from the first radio access network of the first wireless network and from the second radio access network of the second wireless network; 
 wherein the one or more processors are configured to cause the mobile wireless device to:
 determine an unadjusted channel quality metric based at least in part on a downlink signal quality for one or more signals received from the first radio access network of the first wireless network; 
 configure the one or more receivers to receive signals from the second radio access network of the second wireless network for a pre-determined period of time thereby interrupting reception of signals from the first radio access network of the first wireless network; 
 re-configure the one or more receivers from the second radio access network of the second wireless network back to receive signals from the first radio access network of the first wireless network; 
 determine a channel quality metric adjustment value; 
 compute an adjusted channel quality metric based at least in part on the unadjusted channel quality metric and the channel quality metric adjustment value; and 
 send the adjusted channel quality metric to the first radio access network of the first wireless network. 
 
 
     
     
       14. The mobile wireless device recited in  claim 13 , wherein the one or more processors determine the channel quality metric adjustment value based at least in part on a duration of the pre-determined period of time. 
     
     
       15. The mobile wireless device recited in  claim 13 , wherein the adjusted channel quality metric comprises a channel quality indicator (CQI), a rank indicator (RI), or both. 
     
     
       16. The mobile wireless device recited in  claim 13 , wherein the mobile wireless device sends the adjusted channel quality metric to the first radio access network of the first wireless network at least once before configuring the one or more receivers to receive signals from the second radio access network of the second wireless network and at least once after re-configuring the one or more receivers from the second radio access network of the second wireless network back to receive signals from the first radio access network of the first wireless network. 
     
     
       17. The mobile wireless device recited in  claim 13 , wherein computing the adjusted channel quality metric comprises increasing the unadjusted channel quality metric by the channel quality metric adjustment value to compensate for an estimated penalty applied by a network element of the first radio access network due to connection interruption for the pre-determined period of time to an allocation of transmission resources in a downlink direction to the mobile wireless device. 
     
     
       18. The mobile wireless device recited in  claim 13 , wherein the one or more processors are further configured to cause the mobile wireless device to send the adjusted channel quality metric to the first radio access network repeatedly for a number of times based at least in part on a duration of the pre-determined period of time. 
     
     
       19. The mobile wireless device recited in  claim 13 , wherein the one or more processors are further configured to cause the mobile wireless device to:
 estimate a Doppler shift at the mobile wireless device; and 
 determine the channel quality metric adjustment value at least in part based on the estimated Doppler shift. 
 
     
     
       20. A non-transitory computer-readable medium storing instructions for reporting channel quality metrics by a mobile wireless device to a first radio access network of a first wireless network, the instructions, when executed by one or more processors of the mobile wireless device, causing the mobile wireless device to:
 determine an unadjusted channel quality metric based at least in part on a downlink signal quality measured at the mobile wireless device for one or more signals received over a connection from the first radio access network; 
 detect an actual or forthcoming interruption of the connection between the mobile wireless device and the first radio access network during which reception of signals from and/or transmission of signals to the first radio access network are interrupted for a period of time, followed by a resumption of the connection between the mobile wireless device and the first radio access network; and 
 in response to detecting the actual or forthcoming interruption of the connection between the mobile wireless device and the first radio access network: 
 determine a channel quality metric adjustment value; 
 compute an adjusted channel quality metric based at least in part on the unadjusted channel quality metric and the channel quality metric adjustment value; and 
 transmit the adjusted channel quality metric over the connection to the first radio access network.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/655,992, filed Jun. 5, 2012 and entitled “LINK ADAPTATION RESUMPTION BASED ON CQI OFFSET,” and which is incorporated by reference herein in its entirety for all purposes. 
    
    
     TECHNICAL FIELD 
     The described embodiments generally relate to methods and apparatuses for managing radio connections between mobile wireless devices and one or more wireless networks. More particularly, the present embodiments describe lower layer signaling management between a mobile wireless device and a wireless network upon resumption of transmission following a connection interruption. 
     BACKGROUND 
     Wireless networks continue to evolve as new communication technologies develop and standardize. Wireless network operators can deploy new communication technologies in parallel with earlier generation communication technologies, and wireless networks can support multiple communication technologies simultaneously to provide smooth transitions through multiple generations of mobile wireless devices. Mobile wireless devices can include hardware and software to support wireless connections to different types of wireless networks that use different wireless communication technologies. A representative wireless network can include simultaneous support for the Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) wireless communication protocol and the Third Generation Partnership Project 2 (3GPP2) CDMA2000 1x (also referred to as 1xRTT or 1x) wireless communication protocol. This representative “simultaneous” wireless network can support circuit switched voice connections through a first wireless access network that uses the CDMA2000 1x wireless communication protocol and packet switched connections (voice or data) through a second wireless access network that uses the LTE wireless communication protocol. The 3GPP wireless communications standards organization develops mobile communication standards that include releases for Global System for Mobile Communications (GSM), General Packet Radio Service (GPRS), Universal Mobile Telecommunications System (UMTS), LTE and LTE Advanced standards. The 3GPP2 wireless communications standards organization develops mobile communication standards that include CDMA2000 1xRTT and 1xEV-DO standards. While a dual network mobile wireless device that includes support for both CDMA2000 1x and LTE is described as a representative device herein, the same teachings can be applied to other mobile wireless devices that can operate in dual (or more generally multiple) wireless communication technology networks. In particular, the teachings disclosed herein can pertain to mobile wireless devices that switch transceivers from one wireless technology to another wireless technology and back again. The teachings provided herein can also apply to mobile wireless devices that operate under widely varying communication channel conditions using a single wireless technology, e.g., when a mobile wireless device encounters a deep fade that interrupts transmission and/or reception between the mobile wireless device and a wireless access network. 
     Dual chip mobile wireless devices can include separate signal processing chips that each can support a different wireless communication protocol, such as a signal processing chip for a CDMA2000 1x wireless network and another signal processing chip for a LTE wireless network. In particular, in a dual chip mobile wireless device, each signal processing chip can include its own receive signal processing chain, including in some instances multiple receive antennas and attendant signal processing blocks for each signal processing chip. With separate radio frequency receive signaling chains available to each signal processing chip in the dual chip mobile wireless device, pages can be received independently from two different wireless networks, such as from the CDMA2000 1x wireless network and from the LTE wireless network, by the dual chip mobile wireless device. Even when the dual chip mobile wireless device is connected and actively transferring data through one of the signal processing chips to one of the wireless networks, such as the LTE wireless network, the dual chip mobile wireless device can also listen for and receive a paging message through the other parallel signal processing chip from a second wireless access network, such as the CDMA2000 1x wireless network. Thus, the dual chip mobile wireless device can establish a mobile device originating or mobile device terminating circuit switched voice connection through the CDMA2000 1x wireless network while also being actively connected to (or simultaneously camped on) a packet switched LTE wireless network. Dual chip mobile wireless devices, however, can consume more power, can require a larger physical form factor and can require additional components (and cost more) than a more integrated “single chip” mobile wireless device. 
     A single chip mobile wireless device, at least in some configurations, can include a signal processing chip that can support different wireless communications protocols but can be unable to be actively connected to a first wireless access network and to receive communication from a second wireless access network simultaneously. The single chip mobile wireless device can support multiple wireless communication technologies, such as connections to a CDMA2000 1x wireless network and to an LTE wireless network, but only to one wireless network at any given time. The single chip mobile wireless device can be limited to receiving signals that use one wireless communication technology type at a time, particularly when multiple antennas are used to receive signals for a single communication technology that supports receive diversity. In a representative embodiment, a single chip mobile wireless device is able to connect to or camp on an evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (eUTRAN) of the LTE wireless network and also to connect to or camp on a radio access network (RAN) of the CDMA2000 1x wireless network, but not to both wireless networks simultaneously. The single chip mobile wireless device can be registered on both the LTE wireless network and on the CDMA2000 1x wireless network and can therefore form connections with each wireless network singly but not simultaneously. The single chip mobile wireless device can be connected on the LTE wireless network and can interrupt the connection to the LTE wireless network to maintain registration on the CDMA2000 1x wireless network. During the interrupted connection, control signaling and responses to received transmissions between the mobile wireless device and the wireless access network portion of the LTE wireless network can be interrupted. Upon resumption of the connection to the LTE wireless network by the mobile wireless device, downlink transmissions can be restricted to lower data rates by the wireless access network than can be supported by the communication channel signal quality characteristics, as the base station of the wireless access network can interpret the interrupted connection as a poor quality connection. The mobile wireless device is able to receive higher data rates than allocated by the wireless access network, however, the base station of the wireless access network can assign lower data rates to the mobile wireless device for a period of time, thereby unnecessarily penalizing downlink performance to the mobile wireless device. Thus, there exists a need to compensate for connection interruptions between a mobile wireless device and a wireless access network to improve performance of connections upon resumption of the connection. 
     This application describes methods by which a mobile wireless device can operate in a multiple wireless network environment and/or a time varying single network environment and optimize throughput performance after connection interruptions between the mobile wireless device and an access network portion of a wireless network. 
     SUMMARY OF THE DESCRIBED EMBODIMENTS 
     Broadly speaking, the described embodiments relate to managing radio resources and connections between mobile wireless devices and one or more wireless networks. More specifically, methods, apparatuses and computer readable media are described that adjust signaling messages between a mobile wireless device and a wireless network before and/or after a connection interruption to improve downlink performance. 
     In an embodiment, a method to report channel quality metrics by a mobile wireless device to a first wireless access network is described. The method includes at least the following steps executed by the mobile wireless device. The mobile wireless device determines an unadjusted channel quality metric based at least in part on a signal quality measured at the mobile wireless device for one or more signals received over a connection from the first wireless access network. The mobile wireless device detects an interruption of the connection between the mobile wireless device and the first wireless access network followed by a resumption of the connection between the mobile wireless device and the first wireless access network. The mobile wireless device determines a channel quality metric adjustment value. The mobile wireless device computes an adjusted channel quality metric based on the unadjusted channel quality metric and the channel quality metric adjustment value. The mobile wireless device transmits the adjusted channel quality metric over the connection to the first wireless access network. In a representative embodiment, the adjusted channel quality metric includes a channel quality indicator (CQI), a rank indicator (RI), or both. 
     In another embodiment, a mobile wireless device is described. The mobile wireless device includes at least one or more processors, a transmitter and one or more receivers. The one or more processors are configured to control establishing and releasing connections between the mobile wireless device and a first wireless access network and a second wireless access network. The transmitter is configured to transmit signals to the first wireless access network according to a first wireless communication protocol and to the second wireless access network according to a second wireless communication protocol. The one or more receivers are configured to receive signals from the first and second wireless access networks. The one or more processors are further configured to determine an unadjusted channel quality metric based at least in part on a signal quality for one or more signals received by the mobile wireless device from the first wireless access network. The one or more processors are also configured to configure the one or more receivers to receive signals from the second wireless access network for a pre-determined period of time. The one or more processors are further configured to re-configure the one or more receivers of the mobile wireless device from the second wireless access network to receive signals from the first wireless access network. The one or more processors of the mobile wireless device are also configured to determine a channel quality metric adjustment value and to compute an adjusted channel quality metric based on the unadjusted channel quality metric and the determined channel quality metric adjustment value. The one or more processors are configured to provide the adjusted channel quality metric to the transmitter to send to the first wireless access network. In a representative embodiment, the one or more processors of the mobile wireless device determine the channel quality metric adjustment value based at least in part on the pre-determined period of time for an interruption of the connection to the first wireless access network. 
     In another embodiment, a computer program product encoded as computer program code in a non-transitory computer readable medium for reporting channel quality metrics from a mobile wireless device to a first wireless access network is described. The computer program product includes at least the following computer program code. Computer program code for determining an unadjusted channel quality metric based at least in part on a signal quality measured at the mobile wireless device for one or more signals received over a connection from the first wireless access network. Computer program code for detecting an interruption of the connection between the mobile wireless device and the first wireless access network followed by a resumption of the connection between the mobile wireless device and the first wireless access network. Computer program code for determining a channel quality metric adjustment value. Computer program code for computing an adjusted channel quality metric based on the unadjusted channel quality metric and the channel quality metric adjustment value. Computer program code for transmitting the adjusted channel quality metric over the connection to the first wireless access network. In a representative embodiment, the computer program code determines the channel quality metric adjustment value at least in part based on estimating a maximum penalty applied by a network element of the first wireless access network to an allocation of transmission resources in the downlink direction to the mobile wireless device. 
    
    
     
       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. 
         FIG. 1  illustrates components of a generic wireless communication network. 
         FIG. 2  illustrates components of a CDMA2000 1x (RTT or EV-DO) wireless communication network. 
         FIG. 3  illustrates components of an LTE (or LTE-Advanced) wireless communication network. 
         FIG. 4  illustrates a mobile wireless device communicating in parallel to the CDMA2000 1x (RTT or EV-DO) wireless communication network of  FIG. 2  and the LTE (or LTE-Advanced) wireless communication network of  FIG. 4 . 
         FIG. 5  illustrates elements of a prior art dual signal processing chip mobile wireless device. 
         FIG. 6  illustrates elements of a representative single signal processing chip mobile wireless device. 
         FIG. 7  illustrates several transmission modes using one or more antennas of the mobile wireless device. 
         FIG. 8  illustrates a representative method to report channel quality metrics by a mobile wireless device to a wireless access network. 
         FIG. 9  illustrates another representative method to report channel quality metrics by the mobile wireless device to the wireless access network. 
     
    
    
     DETAILED DESCRIPTION OF SELECTED EMBODIMENTS 
     Wireless networks continue to evolve as network operators deploy equipment for new wireless communication technologies based on ongoing standardization efforts. Mobile wireless devices can provide capabilities to communicate with wireless networks based on two or more different wireless communication technologies, e.g. GSM and UMTS, UMTS and LTE, or CDMA2000 1x and LTE, as newer wireless network technologies offer advanced capabilities in parallel with earlier wireless network technologies that can provide greater geographic area coverage and/or varying wireless service implementations. Different wireless communication technologies can require different hardware and software processing to transmit and receive wireless signals, and a mobile wireless device can include multiple, separate signal processing chips to encode and decode wireless signals according to the different wireless communication technologies. A dual chip mobile wireless device, for example, can include one chip for a CDMA2000 1x wireless network and a second chip for an LTE wireless network. With sufficient parallel analog hardware, the dual chip mobile wireless device can communicate with one or both of the wireless networks simultaneously. Dual chip mobile wireless devices, however, can be more complex, larger, more costly and more power intensive than single chip mobile wireless devices. In some embodiments, a single chip mobile wireless device can provide a simpler, smaller, more cost effective and more power efficient mobile wireless device than a dual chip mobile wireless device. The single chip mobile wireless device can communicate with one wireless network at a time out of multiple wireless networks and can provide limited (if any) simultaneous connection capabilities for other parallel wireless networks. 
     It should be understood that implementations of the same methods and apparatuses described herein can apply to mobile wireless devices that operate in different types of wireless networks, particularly one or more wireless networks that offer connections using two or more different generations or types of wireless communication protocols. For example, the same teachings can be applied to a combination of GSM and UMTS networks, LTE and UMTS networks, LTE and CDMA2000 1x networks or other “combined” multiple radio access technology (multi-RAT) wireless networks. A specific example and implementation described herein in relation to CDMA2000 1x-RTT and LTE wireless networks is presented for simplicity, but the methods and apparatuses disclosed herein can also apply equally to other wireless network environments that use other combinations of wireless access communication protocols. The methods and apparatuses described herein can apply to mobile wireless devices in which a connection to a wireless access network is interrupted and then later resumed. Interruption of the connection between the mobile wireless device and the wireless access network can occur when the mobile wireless device switches one or more receivers to operate on a second wireless access network, e.g., to listen for signaling messages from the second wireless access network, thereby interrupting a connection to the first wireless access network. Interruption of the connection to a wireless access network can also occur when a mobile wireless device encounters an extended time interval with poor signal receive signal quality, e.g., during a deep multi-path signal fade. Upon resumption of a connection between the mobile wireless device and the wireless access network, e.g., in response to switching a receiver back to a first wireless access network (from a second wireless access network) or to improved signal quality reception by the mobile wireless device, a downlink data allocation by the wireless access network to the mobile wireless device can be lower than can be supported based on receive signal conditions at the mobile wireless device. The mobile wireless device can report signal quality to the wireless access network, but the wireless access network can downgrade the reported signal quality based on the interruption of the connection to the mobile wireless device. In the embodiments disclosed herein, the mobile wireless device can determine and communicate signaling message information to the wireless access network to compensate for the perception of poor downlink signal quality by the wireless access network and thereby improve downlink performance, e.g., achieve higher allocations of data in the downlink direction from the wireless access network to the mobile wireless device. 
     In some embodiments described herein, a single chip mobile wireless device can be capable of receiving wireless radio frequency signals from an LTE wireless network or from a CDMA2000 1x wireless network individually but not from both wireless networks simultaneously (or in some instances, with only limited reception capabilities from both wireless networks simultaneously). Initially, the single chip mobile wireless device can be associated with the LTE wireless network, e.g. connected to or camped on the LTE wireless network. The single chip mobile wireless device can be registered simultaneously with both the LTE wireless network and with the CDMA2000 1x wireless network. The single chip mobile wireless device can interrupt a packet switched data connection with the LTE wireless network in order to communicate with the CDMA2000 1x wireless network, e.g., to listen for a page addressed to the mobile wireless device for a mobile terminated circuit switched voice connection to the CDMA2000 1x wireless network. Alternatively, the single chip mobile wireless device can interrupt the connection with the LTE wireless network in order to communicate with the CDMA2000 1x wireless network to maintain registration of the mobile wireless device on the CDMA2000 1x wireless network. The single chip mobile wireless device can suspend a packet switched data connection with the LTE wireless network in order to communicate with and/or listen to the CDMA2000 1x wireless network; however, a higher layer radio resource connection, such as a connection for signaling between the single chip mobile wireless device and the LTE wireless network, can remain undisturbed during the suspension of the packet switched data connection. (In some embodiments, the LTE wireless network can be unaware that the mobile wireless device suspended communication and can observe a gap in communication between the LTE wireless network and the mobile wireless device.) The single chip mobile wireless device can tune a receiver (with one or more antennas) contained therein away from the LTE wireless network and to the CDMA2000 1x wireless network to listen for paging messages from the CDMA2000 1x wireless network or to transmit signaling messages to the CDMA2000 1x wireless network. The single chip mobile wireless device can subsequently re-tune the receiver back to the LTE wireless network. Interruption of the packet switched data connection (and of a parallel higher layer signaling connection) to the LTE wireless network can be accommodated without the LTE wireless connection being dropped, e.g., when the interruption is less than any timer expiration limits that would precipitate dropping the connection with the mobile wireless device. Active data transfer between the LTE wireless network and the single chip mobile wireless device as well as signaling messages during the suspension period can be interrupted and later resumed when the mobile wireless device returns to the LTE wireless network. During the interruption, the LTE wireless network can send data packets to the mobile wireless device and can receive no acknowledgement (ACK) messages or any negative acknowledgement (NACK) messages in response, and as a result, the LTE wireless network can interpret the interruption as an indication of poor downlink performance of the communication channel between the LTE wireless access network and the mobile wireless device. In some embodiments, the mobile wireless device can encounter a deep multi-path fade that also interrupts communication between the LTE wireless network and the mobile wireless device for a period of time. During the loss of connection between the mobile wireless device and the LTE wireless network, the LTE wireless network can receive no signaling messages, e.g., including those that carry channel quality information or packet acknowledgement responses, and as a result the LTE wireless network can downgrade the estimated performance of the downlink to the mobile wireless device. 
     When the connection between the mobile wireless device and the LTE wireless network resumes, the LTE wireless network can penalize downlink performance to the mobile wireless device based on the temporary loss of the previous connection between the mobile wireless device and the LTE wireless network. The mobile wireless device can report downlink communication channel signal quality information to the LTE wireless network, e.g., by sending channel quality indicator (CQI) reports, but the LTE wireless network can adjust an estimate of the channel quality for the communication channel to the mobile wireless device downward based on the connection loss, e.g., by estimating a higher block error rate for the present connection as a result of packet loss that occurred during the path connection loss. The LTE wireless network, due to a perceived high block error rate, can penalize the downlink performance from the LTE wireless network to the mobile wireless device unnecessarily until the block error rate estimated by the LTE wireless network improves, e.g., as a result of receiving acknowledgements confirming successful packet reception by the mobile wireless device following resumption of the interrupted connection to the mobile wireless device. To compensate for the downgrade by the LTE wireless network, the mobile wireless device can temporarily upgrade signal quality information sent to the LTE wireless network, e.g., by sending CQI reports with higher values and/or a combination of adjusted CQI report values and higher rank indicator (RI) values. The LTE wireless network, in response, can allocate data transmissions in the downlink direction that can be supported by the higher reported signal quality values when the channel quality values are simultaneously adjusted downward by the LTE wireless network due to higher block error rate values that can occur following a temporary connection loss. The mobile wireless device can upgrade the signal quality information before and/or after the connection with the LTE wireless network is interrupted. The amount by which the signal quality information can be adjusted can be based on the type of wireless network and/or communication protocol used by the wireless network to which the mobile wireless device communicates. The amount by which the signal quality information is adjusted and/or the length of time that signal quality information is adjusted (and/or the number of messages communicated containing adjusted signal quality information) can be pre-determined or adaptively adjusted by the mobile wireless device. The mobile wireless device can determine adjustments for signal quality information to send to the LTE wireless network based on an estimate of the length of time of an interruption of the connection to the LTE wireless network or based on other time varying signal characteristics that can affect the performance of the downlink connection from the LTE wireless network to the mobile wireless device. 
       FIG. 1  illustrates a representative generic wireless network  100  that can include multiple mobile wireless devices  102  connected by radio links  126  to radio sectors  104  provided by a radio access network  128 . Each radio sector  104  can represent a geographic area of radio coverage emanating from an associated radio node  108  using a radio frequency channel operating at a selected frequency. Each radio node  108  can generate one or more radio sectors  104  to which the mobile wireless device  102  can connect by one or more radio links  126 . In some wireless networks  100 , the mobile wireless device  102  can be connected to more than one radio sector  104  simultaneously. The multiple radio sectors  104  to which the mobile wireless device  102  can be connected can emanate from a single radio node  108  or from separate radio nodes  108  that can share a common radio controller  110 . A group of radio nodes  108  together with the associated radio controller  110  can be referred to as a radio access subsystem  106 . Typically each radio node  108  in a radio access subsystem  106  can include a set of radio frequency transmitting and receiving equipment mounted on an antenna tower, and the radio controller  110  connected to the radio nodes  108  can include electronic equipment for controlling and processing transmitted and received radio frequency signals. The radio controller  110  can manage the establishment, maintenance and release of the radio links  126  that connect the mobile wireless device  102  to the radio access network  128 . The radio controller  110  and/or the radio nodes  108  can obtain messages from the mobile wireless devices  102  that include indications of signal quality information for the downlink connections from the radio access subsystem&#39;s  106  of the radio access network  128  to the mobile wireless devices  102 . The radio controller  110  and/or the radio nodes  108  can also monitor characteristics of the connections with the mobile wireless devices  102  to assess the quality of the connections. The radio controller  110  and/or the radio nodes  108  can determine allocations of downlink radio resources to the mobile wireless devices, which can determine downlink data rates to the mobile wireless devices, based at least in part on the signal quality information received from the mobile wireless devices and/or assessments of the connections to the mobile wireless devices  102  by the radio nodes  108  and/or the radio controller  110 . 
     Radio resources that form the radio links  126  in the radio sectors  104  can be shared among multiple mobile wireless devices  102  using a number of different multiplexing techniques, including time division, frequency division, code division, space division and combinations thereof A radio resource control (RRC) signaling connection can be used to communicate between the mobile wireless device  102  and the radio controller  110  in the radio access subsystem  106  of the radio access network  128  including requests for and dynamic allocations of radio resources to multiple mobile wireless devices  102 . Suspension of allocation of radio resources to a mobile wireless device  102  can occur without dis-establishing the radio resource signaling connection to the mobile wireless device  102 . 
     The radio access network  128 , which provides radio frequency air link connections to the mobile wireless device  102 , connects also to a core network  112  that can include a circuit switched domain  122 , usually used for voice traffic, and a packet switched domain  124 , usually used for data traffic. Radio controllers  110  in the radio access subsystems  106  of the radio access network  128  can connect to both a circuit switching center  118  in the circuit switched domain  122  and a packet switching node  120  in the packet switched domain of the core network  112 . The circuit switching center  118  can route circuit switched traffic, such as a voice call, to a public switched telephone network (PSTN)  114 . The packet switching node  120  can route packet switched traffic, such as a “connectionless” set of data packets, to a public data network (PDN)  116 . 
       FIG. 2  illustrates a representative CDMA2000 1x wireless network  200  that can include elements comparable to those described for the generic wireless network  100  shown in  FIG. 1 . Multiple mobile stations  202  can connect to one or more radio sectors  204  through radio frequency links  226 . Each radio sector  204  can radiate outward from a base transceiver station (BTS)  208  that can connect to a base station controller (BSC)  210 , together forming a base station subsystem (BSS)  206 . Multiple base station subsystems  206  can be aggregated to form a radio access network  228 . Base station controllers  210  in different base station subsystems  206  can be interconnected. The base station controllers  210  can connect to both a circuit switched domain  222  that use multiple mobile switching centers (MSC)  218  and a packet switched domain  224  formed with packet data service nodes (PDSN)  220 , which together can form a core network  212  for the wireless network  200 . As with the generic wireless network  100  described above, the circuit switched domain  222  of the core network  212  can interconnect to the PSTN  114 , while the packet switched domain  224  of the core network  212  can interconnect to the PDN  116 . Establishing connections on the CDMA2000 1x wireless network  200  can depend on the mobile station  202  receiving a page from the BSS  206  indicating an incoming connection. The mobile station  202  can be required to listen for pages during specific paging intervals. Without reception of the page, the mobile station  202  can be unaware of a request to form a connection between the mobile station  202  and the CDMA2000 1x wireless network  200 . 
       FIG. 3  illustrates a representative Long Term Evolution (LTE) wireless network  300  architecture designed as a packet switched network exclusively. A mobile terminal  302  can connect to an evolved radio access network  322  through radio links  326  associated with radio sectors  304  that emanate from evolved Node B&#39;s (eNodeB)  310 . The eNodeB  310  includes the functions of both transmitting and receiving base stations (such as the BTS  208  in the CDMA2000 1x wireless network  200 ) as well as base station radio controllers (such as the BSC  210  in the CDMA2000 1x wireless network  200 ). The equivalent core network of the LTE wireless network  300  is an evolved packet core network  320  including serving gateways  312  that interconnect the evolved radio access network  322  to public data network (PDN) gateways  316  that connect to external internet protocol (IP) networks  318 . Multiple eNodeB  310  can be grouped together to form an eUTRAN  306 . The eNodeB  310  can also be connected to a mobility management entity (MME)  314  that can provide control over connections for the mobile terminal  302 . The eNodeB  310  can control allocation of radio resources for the radio links  326  to the mobile terminals  302 . The eNodeB  310  can determine dynamically an amount of radio resources to allocate to a mobile terminal  302  and a modulation and coding scheme (MCS) to use over connections with each of the mobile terminals  302 . Both the amount of radio resources over time and the MCS used with a mobile terminal can vary dynamically based on changes in available resources and measured (and/or estimated) communication channel conditions. The eNodeB  310  can estimate communication channel performance based on information obtained from the mobile terminals  302 , based on measurements made by the eNodeB  310 , and/or based on estimates of channel performance determined by monitoring the success (or lack thereof) of packet reception by the mobile terminals  302 . When communication channel performance to a mobile terminal  302  appears to drop, the eNodeB  302  can elect to assign fewer radio resources and/or lower data rates for connections to the mobile terminal  302 . The eNodeB  302  can seek to achieve a particular set of performance characteristics for the radio communication link to a mobile terminal  302 , e.g., by setting parameters for the radio communication link to achieve a block error rate at or below a fixed pre-determined level. 
       FIG. 4  illustrates a mobile wireless device  102  in communication with both the LTE wireless network  300  and with the CDMA2000 1x wireless network  200 . The CDMA2000 1x wireless network  200  can connect to the circuit switch based public switched telephone network (PSTN)  114  through a mobile switching center (MSC)  218 . The MSC  218  of the CDMA2000 1x wireless network  200  can be interconnected to the MME  314  of the LTE wireless network  300  to coordinate call signaling for the mobile wireless device  102 . In some embodiments, the CDMA2000 1x wireless network  200  can seek to establish a connection through the radio links  226  with the mobile wireless device  102 , e.g. to establish a voice connection between the mobile wireless device  102  and the PSTN  114 . The CDMA2000 1x wireless network  200  can transmit a page message to the mobile wireless device  102  using the radio links  226  to indicate the availability of an incoming voice connection. Unless a receiver in the mobile wireless device  102  is tuned to listen for the page message from the CDMA2000 1x wireless network  200  during the appropriate paging interval, the mobile wireless device  102  can be connected to the LTE wireless network  300  during the paging interval and can be unaware of the incoming voice connection. A dual chip mobile wireless device  102  can be connected to the LTE wireless network  300  and listen to the CDMA2000 1x wireless network  200  simultaneously, but a single chip mobile wireless device  102  with limited receive capabilities can be only capable of listening to one cellular wireless network at a time. The single chip mobile wireless device  102  can periodically listen for page messages from the CDMA2000 1x wireless network  200  by tuning a receiver from the LTE wireless network  300  to the CDMA2000 1x wireless network  200  temporarily and subsequently re-tuning the receiver back to the LTE wireless network  300 . Signaling messages and/or data packets from the LTE wireless network  300  can be dropped while the signal chip mobile wireless device  102  listens for messages from or communicates signaling messages to the CDMA2000 1x wireless network  200 . Without receipt of acknowledgement messages for data packets sent to the mobile wireless device  102 , the LTE wireless network  300  can conclude that the communication link to the mobile wireless device  102  is unreliable. As a result, when the mobile wireless device returns to communicating over the radio links  326  to the radio sector  304  of the eNodeB  310  of the LTE wireless network  300 , the eNodeB  310  can downgrade communications to the mobile wireless device  102  for a period of time. As described further herein, the mobile wireless device  102  can compensate for this undesired behavior of the LTE wireless network  300  by adjusting signal quality information provided to the LTE wireless network  300 . In some embodiments, the mobile wireless device  102  can adjust channel quality indicator (CQI) values provided to the LTE wireless network  300 . In some embodiments, the mobile wireless device  102  can adjust rank indicator (RI) values and CQI values provided to the LTE wireless network  300 . In some embodiments, the mobile wireless device  102  can provide adjusted CQI values and/or adjusted RI values before and/or after an interruption of a connection with the LTE wireless network  300 . In some embodiments, the mobile wires device  102  can select adjusted CQI values and/or adjusted RI values based on a length of time of an interruption of a connection with the LTE wireless network.  300 . In some embodiments, the mobile wireless device  102  can select adjusted CQI values and/or adjusted RI values based on an estimated Doppler shift for movement of the mobile wireless device  102  relative to the eNodeB  310  of the LTE wireless network  300 . 
       FIG. 5  illustrates select wireless signal processing elements  500  that can be contained in a prior art dual chip wireless transmitter/receiver (TX/RX)  516  within a dual chip mobile wireless device  102 . An LTE signal processing chip  502  can be used for connections between the dual chip mobile wireless device  102  and the LTE wireless network  300 , while a CDMA2000 1x signal processing chip  504  can be used for connections between the dual chip mobile wireless device  102  and the CDMA2000 1x wireless network  200 . Each signal processing chip can be connected to a set of antennas through which radio frequency signals can be transmitted and received with respective wireless networks. The LTE signal processing chip  502  can be connected to a transmitting antenna  506  and to a pair of receive antennas  508 / 510 . Multiple receive antennas can be used to improve performance through various forms of receive diversity and can be required based on a standardized wireless communication protocol. With the separate CDMA2000 1x signal processing chip  504 , the dual chip mobile wireless device  102  can transmit and receive radio frequency signals with the CDMA2000 1x wireless network  200  through a transmit antenna  512  and a receive antenna  514 , while simultaneously transmitting and receiving radio frequency signals with the LTE wireless network  300  through the separate transmit antenna  506  and receive antennas  508 / 510 . The LTE signal processing chip  502  and the CDMA2000 1x signal processing chip  504  can be connected to each other in order to coordinate radio frequency signal communication with their respective wireless networks. The dual chip wireless transmitter/receiver  516 , while flexible, can be more expensive, consume more power and occupy more space than a compact, low power single chip wireless transmitter/receiver as shown in  FIG. 6 . 
       FIG. 6  illustrates a single chip wireless transmitter/receiver  614  that can reside in a single chip wireless mobile wireless device  102  that can communicate with the LTE wireless network  300  or the CDMA2000 1x wireless network  200  separately but not simultaneously. When connected to the LTE wireless network  300 , the single chip mobile wireless device  102  can use a single transmitter (Tx)  608  and dual receivers (Rx)  610 / 612 . When connected to the CDMA2000 1x wireless network  200 , the single chip mobile wireless device  102  can use the single transmitter  608  and either one receiver (Rx  610  or Rx  612 ) or dual receivers (Rx  610  and Rx  612 ). Use of dual receivers for both the LTE wireless network  300  and the CDMA2000 1x wireless network  200  can provide higher receive signal quality and therefore higher data throughput and/or greater connection reliability under adverse signal conditions. An interconnect block  606  can allow either an LTE signal processing  602  block or a CDMA2000 1x signal processing block  604  to transmit and receive radio signals through the transmitter  608  and one or both of the receivers  610 / 612  respectively. Within the single chip wireless mobile wireless device  102 , the single chip wireless transmitter/receiver  614  can be connected to an application processor (not shown) that can perform “higher layer” functions such as establishing connections for applications and forming messages to be communicated with various wireless networks, while the single chip wireless transmitter/receiver  614  can perform “lower layer” functions such as ensuring integrity of transmitted and received radio frequency signals that carry messages for the application processor. 
       FIG. 7  illustrates four different transmission and reception methods that can be used for communication of radio frequency signals between the mobile wireless device  102  and network elements of radio access networks  228 / 322  of wireless networks  200 / 300 . Multiple transmit and/or receive antennas can be used for transmission signal path diversity to improve performance as well as for spatial multiplexing to increase throughput for communications between the mobile wireless device  102  and the wireless networks  200 / 300 . A single transmitter, single receiver radio frequency channel  700  provides a basic form of communication with one transmitter  702  and one receiver  704  used at each end. A single transmitter, multiple receiver radio frequency channel  710  can provide receive diversity to improve receive signal strength by combining signals received from each of multiple parallel receive antennas at one end. As shown, two different antennas  706  can receive signals from the single transmitter  702 . While only two receive antennas are shown in  FIG. 7 , more than two receive antennas can also be specified by wireless communication protocols and used in advanced mobile wireless devices. Some communication protocols support the use of four or more receive antennas to improve downlink performance to a mobile wireless device  102 . A multiple transmitter, single receiver radio frequency channel  720  can provide a form of transmit diversity by sending the same data (although possibly encoded differently) through each of multiple antennas of a transmitter  708 . The single antenna receiver  704  can combine information received from each of the two transmit antennas of the transmitter  708  to improve receive signal performance. Finally, a multiple transmitter, multiple receiver radio frequency communication channel  730  can provide for a multiple input multiple output (MIMO) form of communication that can both improve receive signal performance and increase data rates. Parallel data streams can be transmitted by each of the multiple transmitting antennas, and the multiple receiving antennas can separate the received signals to reconstruct the parallel data streams. The use of multiple antennas (including both transmit and receive antennas) can be a critical requirement in advanced wireless communication protocols to increase robustness and achieve higher data transmission rates. In some embodiments, the mobile wireless device  102  can indicate a preference for transmissions from the LTE wireless network  300 , e.g., by providing a rank indicator (RI) to the LTE wireless network  300 . A higher value for the RI can communicate to the LTE wireless network  300  a preference for increased data transmission rates by using multiple parallel transmit streams as supported by MIMO communication methods. The mobile wireless device  102  can provide channel quality indicator (CQI) values in conjunction with the RI values to the LTE wireless network  300 , and the LTE wireless network  300  can use both RI values and CQI values to determine modulation and coding schemes to use for transmissions to the mobile wireless device  102 . 
     In a representative embodiment, a mobile wireless device  102 , e.g., including a single chip wireless transceiver  614  or equivalent, can tune the transceiver  614  from a first wireless access network, e.g., an LTE wireless network  300 , to a second wireless access network, e.g., a CDMA2000 1x wireless network  200 . The mobile wireless device  102  can tune the transceiver temporarily to the second wireless access network from the first wireless access network in order to listen for signaling messages from the second wireless access network, e.g., paging messages, or to communicate with the second wireless access network, e.g., to maintain registration with the second wireless access network. The mobile wireless device  102  can subsequently tune the transceiver back to the first wireless access network. While the mobile wireless device is tuned to the second wireless access network, a connection with the first wireless connection can be interrupted, and data packets transmitted from the first wireless access network to the mobile wireless device  102  can be lost. Communication of signaling messages and acknowledgements in response to data packets received from the first wireless access network can be interrupted and not communicated from the mobile wireless device  102  to the first wireless access network during the period that the mobile wireless device  102  is tuned away from the first wireless access network. Similarly, the mobile wireless device  102  can encounter a long time duration multi-path fade while connected to the first wireless access network, the long multi-path fade causing a loss of communication between the mobile wireless device  102  and the first wireless access network. The loss of communication between the mobile wireless device  102  and the first wireless access network can result in an out of synchronization condition. During an interruption of communication, the first wireless access network can receive no reports from the mobile wireless device  102 , e.g., no CQI reports or ACK/NACK messages that can provide signal quality information to the first wireless access network. The mobile wireless device  102  can normally send CQI reports to the first wireless access network based on measurements of downlink signal to interference and noise ratios for signals received at the mobile wireless device  102 . The mobile wireless device  102  can map measurements of received signal to interference plus noise ratio (SINR) to CQI values and report the CQI values to the first wireless access network. The first wireless access network can use the reported CQI values to determine settings for communication links to the mobile wireless device  102 . 
     The eNodeB  310  of the LTE wireless network  300  can allocate a particular modulation and coding scheme (MCS) based at least in part on the reported CQI values received from the mobile wireless device  102 . The eNodeB  310  can also use measures of packet loss (e.g., block error rates) to also influence selection of an MCS to use for communication with the mobile wireless device  102 . As a representative example, the mobile wireless device  102  can measure a “high” SINR value and report a “maximum” CQI value of  15  to the eNodeB  310  of the LTE wireless network  200 . The eNodeB  310  can map the CQI value of  15  to an MCS that uses a dense signaling constellation (e.g., 64 QAM) and a relatively high coding rate (&gt;0.5). The combination of higher coding rate and denser constellation can provide for higher data rate transmission to the mobile wireless device  102  by the eNodeB  310 . Alternatively, the mobile wireless device  102  can measure a “low” SNR value and report a “minimum” CQI value of 1 to the eNodeB  310  of the LTE wireless network  200 , and the eNodeB  310  can map the CQI value of 1 to an MCS that uses a sparse constellation (e.g., QPSK) and a relatively low coding rate (&lt;0.25). The combination of a lower coding rate and sparser constellation can result in lower data rate transmission to the mobile wireless device  102  by the eNodeB  310 . In some embodiments, the eNodeB  310  selects an MCS to achieve a target quality of service (QoS) level and/or a particular target block error rate (BLER) value, e.g., less than 10% block error rate. The eNodeB  310  can use receipt of ACK and NACK messages from the mobile wireless device  102  to determine a block error rate for communication with the mobile wireless device  102 . An ACK message can indicate the mobile wireless device  102  received a packet and decoded the packet with a correct cyclic redundancy check (CRC). A NACK message can indicate the mobile wireless device  102  received a packet and decoded the packet with an incorrect CRC. The eNodeB  310  can use the ACK/NACK messages received from the mobile wireless device  102  to estimate a BLER for the downlink connection to the mobile wireless device  102 . The eNodeB  310  can also use an absence of ACK/NACK messages received from the mobile wireless device  102  after sending data packets to the mobile wireless device  102  to conclude that data packets are lost. Thus, an interrupted connection between the mobile wireless device  102  and the eNodeB  310  can impact an estimate of the BLER determined by the eNodeB  310 . 
     In a representative embodiment, the eNodeB  310  can select an MCS to achieve a target BLER less than a pre-determined value, e.g., less than 10% BLER. When the estimated BLER level achieves the target BLER, the enodeB  102  can select an MCS in accordance with the received CQI values from the mobile wireless device  102 . When the estimated BLER level, however, exceeds the target BLER, the enodeB  102  can downgrade the connection by adjusting the received CQI values lower and thereby selecting an MCS that results in a lower data rate (in order to better achieve the target BLER) for downlink communication to the mobile wireless device  102 . When the mobile wireless device  102  tunes away from the LTE wireless network  300 , the eNodeB  310  can note an absence of ACK/NACK messages from the mobile wireless device  310  and can estimate the BLER value increasing to higher values that can exceed the target BLER value. In some embodiments, for a long “tune-away” time period, the estimated BLER value can reach a maximum value of approximately 100%. In some embodiments, an absence of messages received from the mobile wireless device  102  can be interpreted as a NACK message, and repeated actual (or interpreted) NACKs at the eNodeB  310  can cause the BLER to increase to its maximum value. After the mobile wireless device  102  returns from a “tune-away” with the CDMA2000 1x wireless network  200  to the LTE wireless network  300  (or after a long fade), the eNodeB  310  can continue to estimate that a high BLER exists for the connection to the mobile wireless device  102 . The eNodeB  310  can wait until subsequent ACK messages indicate successful reception of data packets before lowering the BLER estimate, and as a result values for the MCS selected in the interim by the eNodeB  310  can be downgraded based on the estimated high BLER value. For example, the mobile wireless device  102  can report a CQI value of  13  following a “tune-away” period that would normally correspond to an MCS value of  23  when the estimated target BLER of  10 % can be met. The eNodeB  310 , however, can estimate a higher BLER value based on a lack of ACK messages from the mobile wireless device  102  during the tune-away period and penalize downlink communications to the mobile wireless device  102  by selecting a lower MCS value, e.g., an MCS value of  19 , to compensate for the higher estimated BLER value. A high estimated BLER value that follows a tune-away by the mobile wireless device  102  or follows a deep multi-path fade can negatively impact subsequent downlink communications to the mobile wireless device  102 . A method to reduce the MCS penalty assigned after a return from a tune-away or deep multi-path fade can be desired to improve performance of a data connection between the eNodeB  310  of the LTE wireless network  300  and the mobile wireless device  102 . 
     A particular wireless communications protocol can establish a range of values for signal quality metrics, e.g., for channel quality indicator (CQI) values. The LTE wireless network  300  can use a range of CQI values ranging from 1 to 15 to represent different levels of received SINR (and a zero CQI value for an out of range condition). The CQI can be reported by the mobile wireless device  102  to the eNodeB  310  of the LTE wireless network  300  over a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). In a representative embodiment, the CQI can be reported by the mobile wireless device  102  to the eNodeB  310  periodically in a control message on the PUCCH. In another representative embodiment, the CQI can be reported in one or more messages over the PUSCH by the mobile wireless device  102  in response to receiving an indication for a signal quality measurement from the eNodeB  310 . The eNodeB  310  can select an MCS value based on received CQI values (and on other information gathered to estimate downlink performance) to achieve a target BLER, e.g., less than 10%. The mobile wireless device  102  can measure SINR at its receiver and select a CQI value to report to the eNodeB  310 . The selected CQI value can achieve a target BLER, e.g., less than 10%, in the estimation of the mobile wireless device  102 . The mobile wireless device  102  can also include a rank indicator (RI) value to recommend a number of parallel spatial multiplexed data streams for the eNodeB  310  to send to the mobile wireless device  102 . A mobile wireless device  102  with two receive antennas connected with an eNodeB  310  having two transmit antennas can send RI values of 1 or 2 to indicate one or two parallel data streams, while a mobile wireless device  102  with four receive antennas connected with an eNodeB  310  having four transmit antennas can send RI values of 1, 2, 3 or 4. Both the CQI and RI values can be communicated from the mobile wireless device  102  to the eNodeB  310  together, i.e., a reported CQI value can be paired with an accompanying RI value. As higher RI values can correspond to higher data rates (through the use of parallel data transmission), accompanying CQI values can depend on the accompanying RI value. For example, an RI value of 1 and a CQI value of 15 can correspond to a measured SINR condition that equivalently can be represented by an RI value of 2 and a CQI value of 11. Higher RI values can thus be used with CQI values to extend the effective range of SINR conditions that can be represented to the eNodeB  310 . 
     In some embodiments, the mobile wireless device  102  can report different CQI values and/or RI values to the eNodeB  310  before and/or after a tune-away or a long fade. The mobile wireless device  102  can calculate CQI values based on received SINR values and can compensate by increasing the reported CQI values in advance of a planned tune-away period and/or immediately following a tune-away period (or after detecting return from a deep long fade). The higher reported CQI values can affect the downstream MCS values that the eNodeB  310  selects to use with the mobile wireless device  102  in the time period immediately following the tune-away period (or fade). The mobile wireless device  102  can estimate a penalty that can be imposed by the eNodeB  310  due to the tune-away time period (or a fade), e.g., a reduction in estimated downlink signal quality. As described herein, the eNodeB  310  can downgrade a reported CQI based on an estimate of a BLER value higher than a target BLER. The mobile wireless device  102  can report a higher CQI value to compensate for the expected downgrade and thereby achieve a higher downlink throughput than would otherwise occur. In some embodiments, the mobile wireless device  102  can estimate a maximum penalty value (e.g., 6 dB) that can be imposed and can adjust reported CQI values (e.g., increase by a +3 offset) for a period of time to compensate. In some embodiments, the mobile wireless device  102  can report an adjusted CQI value before a tune-away time period, e.g., in anticipation of the effect that the tune-away can have on the eNodeB  310 . In some embodiments, the mobile wireless device  102  can report an adjusted CQI value following the tune-away time period (or following a long deep fade). A value of adjustment applied to the reported CQI values can be based on one or more factors including (1) a duration of the time period of the tune-away, (2) a duration of the time period of a deep fade, (3) an amount of Doppler shift, and/or (4) an estimate of how fast or slow channel conditions are time varying between the mobile wireless device  102  and the eNodeB  310 . The mobile wireless device  102  can also determine (1) when to adjust and report different CQI values, (2) by how much to adjust the reported CQI values, and/or (3) for how long to report adjusted CQI values to the eNodeB  310 . 
     When the mobile wireless device  102  measures relatively high SINR values for signals received from the eNodeB  310 , a maximum CQI value of 15 can be reached, e.g., during high quality communication channel conditions. As the maximum CQI value of 15 cannot be adjusted higher, the mobile wireless device  102  can adjust a rank indicator value in conjunction with an adjustment to the CQI value to report effectively a higher SINR value. Different combinations of RI values and CQI values can correspond to comparable SINR conditions. For example, a mobile wireless device  102  can report an RI value of 1 and a CQI value of 15 or equivalently an RI value of 2 and a CQI value of 11 or 12 for the same measured SINR condition. By using the RI value of 2 instead of the RI value of 1, the latter for which the CQI value can be capped to the maximum value of 15, the mobile wireless device can adjust the reported CQI value upward from 11 or 12 to a higher value in conjunction with the RI value of 2 to report a higher SINR condition to the eNodeB  310 . A higher RI value can provide additional headroom to adjust CQI reported values upward. The mobile wireless device  102  can be capable of supporting either rank  1  or rank  2  transmissions from the eNodeB  310  when reporting an RI value of 2 to the eNodeB  310 . 
       FIG. 8  illustrates a representative method  800  to report channel quality metrics by the mobile wireless device  102  to a first wireless access network. In step  802 , the mobile wireless device  102  determines an adjusted channel quality metric based at least in part on a signal quality metric measured at the mobile wireless device  102  for one or more signals received over a connection from the first wireless access network. In some embodiments, the mobile wireless device  102  determines the unadjusted channel quality metric at regular intervals and transmits information about measurements of the channel quality metrics to the first wireless access network. In some embodiments, the mobile wireless device  102  determines the unadjusted channel quality metric by calculating one or more channel quality metric values before detecting an interruption of the connection between the mobile wireless device  102  and the first wireless access network. In step  804 , the mobile wireless device  102  detects an interruption of the connection between the mobile wireless device  102  and the first wireless access network. In some embodiments, the mobile wireless device  102  tunes one or more receivers of the mobile wireless device  102  from the first wireless access network to receive signals from or transmit signals to a second wireless access network, thereby initiating the interruption of the connection between the mobile wireless device  102  and the first wireless access network. In some embodiments, the mobile wireless device  102  can receive poor signal quality, e.g., due to a deep multi-path fade, that results in the interruption of the connection between the mobile wireless device  102  and the first wireless access network. The time interval of the interruption of the connection between the mobile wireless device  102  and the first wireless access network can be caused by the deep multi-path fade. In step  806 , the mobile wireless device  102  detects resumption of the connection to the first wireless access network. In some embodiments, the mobile wireless device  102  re-tunes the one or more receivers of the mobile wireless device  102  from the second wireless access network back to the first wireless access network, thereby resuming the connection to the first wireless access network. In some embodiments, the length of the time period from the start of the interruption of the connection (when tuning away) to the end of the interruption of the connection (when re-tuning back) can be a pre-determined period of time, e.g., known in advance to the mobile wireless device  102 . In some embodiments, the mobile wireless device  102  receives an improved signal quality, e.g., due to exiting a deep fade condition, thereby resuming the connection between the mobile wireless device  102  and the first wireless access network. In step  808 , the mobile wireless device  102  determines a channel quality metric adjustment value. In some embodiments, the mobile wireless device  102  determines the channel quality adjustment metric value by estimating a maximum penalty applied by a network element of the first wireless access network to an allocation of transmission resources in the downlink direction to the mobile wireless device  102 . In step  810 , the mobile wireless device  102  computes an adjusted channel quality metric based on the unadjusted channel quality metric and the channel quality metric adjustment value. In some embodiments, the adjusted channel quality metric includes a channel quality indicator (CQI), a rank indicator (RI), or both. In step  812 , the mobile wireless device  102  transmits the adjusted channel quality metric over the connection to the first wireless access network. 
     In some embodiments, the mobile wireless device  102  calculates the channel quality metric adjustment value based on an estimated downlink block error rate of approximately  100  percent. The mobile wireless device  102  can also calculate the channel quality metric adjustment value based on an estimate of the length of time for the interruption of the connection between the mobile wireless device  102  and the first wireless access network. In some embodiments, the mobile wireless device  102  determines the channel quality metric adjustment value based at least in part on a pre-determined period of time for tuning away from the first wireless access network and re-tuning back to the first wireless access network. The mobile wireless device  102  can estimate an downlink block error rate that can accumulate over time during the interruption of the connection between the mobile wireless device  102  and the first wireless access network, e.g. a downlink block error rate estimated in parallel by a network element of the first wireless access network. The mobile wireless device  102  can calculate the channel quality metric adjustment value to compensate for the estimated downlink block error rate, which the network element of the first wireless access network can use to downgrade signal quality estimates for the connection to the mobile wireless device  102 . The mobile wireless device  102  can adjust a reported channel quality indicator (CQI), e.g., increase the CQI value, based on the calculated channel quality metric adjustment. The mobile wireless device  102  can also adjust a rank indicator (RI), e.g., increase the RI value when less than a maximum RI value, in conjunction with reporting a CQI value to the first wireless access network. The mobile wireless device  102  can provide an adjusted RI value and an adjusted CQI value together to the first wireless access network. In some embodiments, the unadjusted channel quality metric can be a maximum CQI value, and the mobile wireless device can increase an accompanying RI value in conjunction with providing a CQI value (adjusted or unadjusted) to the first wireless access network  102 . The combination of the CQI value and the adjusted RI value can compensate at least in part for a penalty that the first wireless access network can apply to downlink transmissions, e.g., as a result of estimating a high block error rate when the connection between the mobile wireless device  102  and the first wireless access network is interrupted and then later resumed. 
     The mobile wireless device  102  can transmit an adjusted channel quality metric, e.g., report adjusted CQI values and/or adjusted RI values, to the first wireless access network one or more times before the interruption of the connection with the first wireless access network and/or one or more times after resumption of the connection with the first wireless access network. The mobile wireless device  102  can transmit at least one adjusted CQI value to the first wireless access network before adjusting a receiver of the mobile wireless device to receive signals from the second wireless access network. In some embodiments, the mobile wireless device  102  can interrupt the connection to the first wireless access network to listen for signaling messages from or to transmit signaling messages to a second wireless access network. When the mobile wireless device  102  controls the interruption of the connection to the first wireless access network, the mobile wireless device  102  can determine one or more adjusted channel quality metrics and transmit the one or more adjusted channel quality metrics to the first wireless access network at least once before the interruption of the connection with the first wireless access network. Upon resumption of the connection with the first wireless access network, the mobile wireless device  102  can transmit adjusted channel quality metrics determined before and/or determined after the interruption of the connection. In some embodiments, the mobile wireless device  102  transmits at least once an adjusted channel quality metric that was determined before the interruption of the connection upon resumption of the connection. The mobile wireless device  102  can subsequently determine and update adjusted channel quality metrics to transmit to the first wireless access network after the connection to the first wireless access network resumes. 
     When the mobile wireless device  102  controls an interruption of the connection to the first wireless access network, the mobile wireless device  102  can determine an adjustment of channel quality metrics to report to the first wireless access network based on knowledge of a pre-determined time period for the interruption of the connection to the first wireless access network. The mobile wireless device  102  can adjust the channel quality metric at least in part based on the length of the pre-determined time period for the interruption of the connection. In some embodiments, the mobile wireless device  102  can estimate the time period of the interruption of the connection during and/or after resumption of the connection with the mobile wireless device. The mobile wireless device  102  can determine an adjustment to the channel quality metrics based on the estimate of the time period of the interruption. In some embodiments, the mobile wireless device can determine a number of times to transmit an adjusted channel quality metric to the first wireless access network based on the estimated time period of the interruption of the connection. For example, longer interruptions can result in higher estimates of block error rates by the first wireless access network, while shorter interruptions can result in lower estimates of block error rates by the first wireless access network. The mobile wireless device  102  can account for the effect that the length of time of the interruption can impact the estimated block error rate to determine adjustment values for the channel quality metrics and/or the number of times to transmit adjusted channel quality metrics to the first wireless access network based at least in part on the length of time of the interruption (whether known in advance, measured, or estimated by the mobile wireless device  102 .) The mobile wireless device  102  can transmit adjusted channel quality metrics for the determined number of times following a resumption of the connection with the first wireless access network. By sending adjusted channel quality metrics repeatedly to the first wireless access network, the mobile wireless device  102  can influence the selection of modulation coding schemes that the first wireless access network assigns to the mobile wireless device  102 . 
     The mobile wireless device  102  can account for a type of communication protocol used for connections between the first wireless access network and the mobile wireless device  102  when determining a channel quality metric adjustment. Different communication protocols can have different ranges of channel quality metric values, can have different correlations of the channel quality metric values to changes in signal quality, can have different algorithms for determining block error rates, and/or can have different algorithms for combining reported channel quality metrics with determined block error rates for determining modulation coding schemes to use for assigning resources in the downlink direction to the mobile wireless device  102 . In some embodiments, the mobile wireless device  102  can account for the type of communication protocol used on connections with the first wireless access network to determine the adjusted channel quality metric values and/or a number of times to transmit adjusted channel quality metric values to the first wireless access network. The mobile wireless device  102  can determine at least in part how a lack of acknowledgement (ACK and/or NACK) messages during the interruption of the connection with the first wireless access network can impact a block error rate estimate, which in turn can affect a selection of modulation and coding schemes assigned to the mobile wireless device  102  by the first wireless access network. Until the estimated block error rate returns to a target block error rate, the first wireless access network can penalize transmissions to the mobile wireless device  102 , e.g., by downgrading reported channel quality metrics received from the mobile wireless device  102  based on the estimated block error rate. The mobile wireless device  102  can report adjusted channel quality metrics to the first wireless access network to compensate for this downgrading effect caused by the higher estimated block error rates. 
       FIG. 9  illustrates another representative method  900  to report channel quality metrics by the mobile wireless device  102  to a first wireless access network. In step  902 , the mobile wireless device  102  determines an unadjusted channel quality metric. In step  904 , the mobile wireless device  102  configures one or more receivers of the mobile wireless device  102  from the first wireless access network to a second wireless access network. In step  906 , the mobile wireless device  102  re-configures the one or more receivers from the second wireless access network back to the first wireless access network. In some embodiments, the length of time that the one or more receivers of the mobile wireless device  102  are configured to receive signals from the second wireless access network is a pre-determined time period. In step  908 , the mobile wireless device  102  determines a channel quality metric adjustment value. In some embodiments, the mobile wireless device  102  determines the channel quality metric adjustment value based at least in part on the length of time that the one or more receivers are tuned to the second wireless access network. In step  910 , the mobile wireless device  102  computes an adjusted channel quality metric, e.g., based on the unadjusted channel quality metric and the channel quality metric adjustment value. In some embodiments, the channel quality metrics (adjusted and/or unadjusted) are CQI values, RI values, or both. In step  912 , the mobile wireless device  102  provides the adjusted channel quality metric to a transmitter in the mobile wireless device  102  to transmit to the first wireless access network. In some embodiments, the mobile wireless device  102  transmits the adjusted channel quality metric at least once before configuring the one or more receivers to the second wireless access network. In some embodiments, the mobile wireless device  102  transmits the adjusted channel quality metric at least once after re-configuring the one or more receivers from the second wireless access network back to the first wireless access network. 
     The mobile wireless device  102  can include one or more processors configured to control establishing and releasing connections between the mobile wireless device  102  and one or more wireless access networks, including a first wireless access network and a second wireless access network. The mobile wireless device  102  can include a transmitter configured to transmit signals to the first wireless access network according to a first wireless communication protocol and to the second wireless access network according to a second wireless communication protocol. In a representative embodiment, the first wireless communication protocol is an LTE or LTE-Advanced wireless communication protocol, and the second wireless communication protocol is a CDMA2000 1x wireless communication protocol. The mobile wireless device  102  can include one or more receivers configured to receive signals from the first and second wireless access networks. The one or more processors of the mobile wireless device  102  can be configured to determine an unadjusted channel quality metric based at least in part on a signal quality for one or more signals received by the mobile wireless device  102  from the first wireless access network. The mobile wireless device  102  can measure received signal quality, e.g. determining an SINR value, and can communicate signal quality metrics to the first wireless access network, e.g., CQI and/or RI values. In some embodiments, CQI values are transmitted to the first wireless access network as “unadjusted” channel quality metrics. In some embodiments, CQI values are “adjusted” by the mobile wireless device  102  before being transmitted as “adjusted” channel quality metric values to the first wireless access network. The one or more processors of the mobile wireless device  102  can be configured to tune the one or more receivers to receive signals from a second wireless access network and to subsequently re-tune the one or more receivers to receive signals from the first wireless access network. The one or more processors can be configured to tune the receivers to the second wireless access network for a pre-determined period of time, e.g., to overlap with regular paging intervals used by the second wireless access network. The one or more processors of the mobile wireless device  102  can be configured to determine a channel quality metric adjustment value. The channel quality metric adjustment value can depend on the length of time that a connection between the mobile wireless device  102  and the first wireless access network is interrupted, e.g., due to the tuning of the receivers to the second wireless access network. The one or more processors of the mobile wireless device  102  can compute an adjusted channel quality metric based on the unadjusted channel quality metric and the channel quality metric adjustment value. The one or more processors of the mobile wireless device  102  can be configured to provide the adjusted channel quality metric to the transmitter to send to the first wireless access network. The amount of the adjustment applied to the channel quality metric can depend on a number of factors, including the pre-determined period of time that the mobile wireless device  102  is tuned to the second wireless access network. The adjusted channel quality metric can include a CQI value, an RI value, or both. The adjusted channel quality metrics can be communicated to the first wireless access network before and/or after tuning the receivers to the second wireless access network and back to the first wireless access network. 
     Software, hardware, or a combination of hardware and software can implement various aspects of the described embodiments. The described embodiments can also be encoded as computer program code on a non-transitory computer readable medium. The non-transitory computer readable medium is any data storage device that can store data that can thereafter be read by a computer system. Examples of the non-transitory computer readable medium include read-only memory, random-access memory, CD-ROMs, DVDs, magnetic tape and optical data storage devices. The computer program code can also be distributed over network-coupled computer systems so that the computer program code is stored and executed in a distributed fashion. 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. 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 the specific embodiments described herein are presented for purposes of illustration and description. They are not targeted to be exhaustive or to limit the 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. 
     The advantages of the embodiments described are numerous. Different aspects, embodiments or implementations can yield one or more of the following advantages. Many features and advantages of the present embodiments are apparent from the written description and, thus, it is intended by the appended claims to cover all such features and advantages of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, the embodiments should not be limited to the exact construction and operation as illustrated and described. Hence, all suitable modifications and equivalents can be resorted to as falling within the scope of the invention.

Metadata:
Filing Date: 20130516
Publication Date: 20160119
Grant Date: 20160119
Priority Date: 20120605
Inventors: TABET TARIK
SONG KEE-BONG
MUJTABA SYED A.
KIM YOUNG JAE
DAMJI NAVID
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W72/542", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L27/0008", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/21", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0027", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W72/085", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04B7/0417", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W76/028", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/0026", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L27/2601", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B7/0417", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L27/0008", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/21", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L27/2601", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W76/19", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/21", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L27/2601", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04W76/19", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B17/24", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04B7/0417", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/0027", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0027", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0026", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L27/0008", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/0026", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 49670854