PATENT DOCUMENT

Publication Number: US-9565285-B2
Application Number: US-201414185752-A
Country: US
Kind Code: B2

Title: Cellular network communications wireless headset and mobile device

Abstract:
A headset that communicates with a mobile device through a local radio frequency (RF) communication link to conduct a telephone call is described. The headset includes a local RF communication modem that receives downlink packets from the mobile device through the local RF communication link. The downlink packets were received by the mobile device through a wireless communication link. The headset includes an audio decoder that decodes the downlink packets into a downlink audio signal to be played back at the headset. The headset also includes an audio encoder that encodes an uplink audio signal produced by the headset into uplink packets. The local RF communication modem sends the uplink packets to the mobile device through the local RF communication link. Other embodiments are also described and claimed.

Claims:
What is claimed is: 
     
       1. A headset to communicate with a mobile device through a local radio frequency (RF) communication link to conduct a telephone call, the headset comprising:
 a local RF communication modem that is configured to receive a plurality of downlink packets for the telephone call from the mobile device through the local RF communication link, wherein the plurality of downlink packets were received by the mobile device through a wireless communication link with a far end device; 
 an audio decoder that is configured to decode the plurality of downlink packets into a downlink audio signal to be converted into sound at the headset; 
 an audio encoder that is configured to encode an uplink audio signal produced by the headset for the telephone call into a plurality of uplink packets, wherein the local RF communication modem is to send the plurality of uplink packets to the mobile device through the local RF communication link and wherein the uplink audio signal as encoded in the plurality of uplink packets is not audio encoded in the mobile device, before transmission through the wireless communication link with the far end device; and 
 a composite flow control logic that is configured to:
 control a first data transmission rate for transmitting data from the headset to the mobile device over the local RF communication link, 
 control, through a local flow control logic at the mobile device, a second data transmission rate for transmitting data from the mobile device to the headset over the local RF communication link, and 
 control, through a baseband flow control logic at the mobile device, a third data transmission rate for transmitting data from the mobile device to the far-end device over the wireless communication link, wherein the composite flow control logic comprises a local flow control data interchange for exchanging flow control data with the local flow control logic and the baseband flow control logic. 
 
 
     
     
       2. The headset of  claim 1 , wherein the plurality of uplink and downlink packets are encapsulated inside local RF packets when transmitted over the local RF communication link, wherein the wireless communication link is a cellular communication link. 
     
     
       3. The headset of  claim 1  further comprising audio processing circuitry to perform one or more of the following operations to enhance intelligibility of speech by far-end users: equalization; dynamic range control; noise reduction; and automatic gain control. 
     
     
       4. The headset of  claim 1 , wherein the composite flow control logic is to exchange flow control data with the local flow control logic and the baseband flow control logic by encapsulating the flow control data as a section inside regular local RF data packets that are transmitted over the local RF communication link. 
     
     
       5. The headset of  claim 1 , wherein the composite flow control logic is to exchange flow control data with the local flow control logic and the baseband flow control logic by transmitting the flow control data as flow control packets. 
     
     
       6. The headset of  claim 1  further comprising a call setup logic that is to perform continuous voice activity detection. 
     
     
       7. The headset of  claim 6 , wherein the call setup logic comprises a phrase identification logic that is to identify phrases uttered by a user of the headset. 
     
     
       8. A method for a headset to communicate with a mobile device through a local radio frequency (RF) communication link to conduct a telephone call, the method comprising:
 receiving a first plurality of packets for the telephone call from the mobile device through the local RF communication link; 
 decoding the first plurality of packets into a first audio signal; 
 encoding a second audio signal for the telephone call into a second plurality of packets for the telephone call; 
 sending the second plurality of packets to the mobile device through the local RF communication link wherein the second audio signal, as encoded in the plurality of packets sent to the mobile device, is not audio encoded in the mobile device before transmission through a wireless communication link; 
 controlling, by a composite flow control logic in the headset, a first data transmission rate for transmitting data from the headset to the mobile device over the local RF communication link; 
 controlling, by the composite flow control logic, through a local flow control logic at the mobile device, a second data transmission rate for transmitting data from the mobile device to the headset over the local RF communication link; and 
 controlling, by the composite flow control logic, through a baseband flow control logic at the mobile device, a third data transmission rate for transmitting data from the mobile device to a far-end device over the wireless communication link, wherein the composite flow control logic comprises a local flow control data interchange for exchanging flow control data with the local flow control logic and the baseband flow control logic. 
 
     
     
       9. The method of  claim 8  further comprising:
 processing the first audio signal; and 
 playing back the processed first audio signal through a speaker of the headset. 
 
     
     
       10. The method of  claim 8  further comprising producing the second audio signal through a microphone of the headset. 
     
     
       11. A headset to communicate with a mobile device through a local RF communication link to conduct a telephone call, the headset comprising:
 a local RF communication modem that is to receive a plurality of downlink packets for the telephone call from the mobile device through the local RF communication link, wherein the downlink packets are encapsulated inside local RF packets when transmitted or received over the local RF communication link, and wherein the plurality of downlink packets had been received by the mobile device through a cellular wireless communications link; 
 an audio decoder that is to decode the plurality of downlink packets into a downlink audio signal to be converted into sound at the headset; 
 an audio encoder that is to encode an uplink audio signal produced by the headset for the telephone call into a plurality of uplink packets, wherein the local RF communication modem is to send the plurality of uplink packets to the mobile device through the local RF communication link as the plurality of uplink packets are encapsulated inside local RF packets when transmitted over the local RF communication link; 
 a composite flow control logic that is configured to:
 control a first data transmission rate for transmitting data from the headset to the mobile device over the local RF communication link, 
 control, through a local flow control logic at the mobile device, a second data transmission rate for transmitting data from the mobile device to the headset over the local RF communication link, and 
 control, through a baseband flow control logic at the mobile device, a third data transmission rate for transmitting data from the mobile device to a far-end device over the wireless communication link, wherein the composite flow control logic comprises a local flow control data interchange for exchanging flow control data with the local flow control logic and the baseband flow control logic; 
 
 and wherein the uplink audio signal as it is encoded in the plurality of uplink packets is not subjected to audio decoding in the mobile device when the uplink audio signal is transmitted through the cellular wireless communication link. 
 
     
     
       12. The headset of  claim 11  further comprising audio processing circuitry to perform one or more of the following operations to enhance intelligibility of speech by a far end user during the call: equalization; dynamic range control; noise reduction; and automatic gain control. 
     
     
       13. The headset of  claim 11 , wherein the composite flow control logic is to exchange flow control data with the local flow control logic and the baseband flow control logic by encapsulating the flow control data as a section inside regular local RF data packets that are transmitted over the local RF communication link. 
     
     
       14. The headset of  claim 11 , wherein the composite flow control logic is to exchange flow control data with the local flow control logic and the baseband flow control logic by transmitting the flow control data as flow control packets. 
     
     
       15. The headset of  claim 11  wherein the local RF communication modem is a Bluetooth modem.

Description:
FIELD 
     An embodiment of the invention is related to digital audio signal processing techniques in mobile devices and headsets, and particularly to techniques for decoding/encoding audio packets at mobile devices and headsets. Other embodiments are also described. 
     BACKGROUND 
     A mobile phone (also known as a cellular phone, and a cell phone) enables its user to make and receive telephone calls over a cellular communication network while moving around a wide geographic area. To allow hands-free operation of a mobile phone, a headset is often used alongside the mobile phone during a phone call. A headset has a pair of left and right earphones or headphones combined with a microphone, or one headphone with a microphone, in a way that can be worn by the user in a hands-free manner (e.g., as an over-the-head unit, a tethered and wired unit, a wireless ear worn unit). Headsets provide the equivalent functionality of a telephone handset but with hands-free operation. 
       FIG. 1  illustrates a detailed diagram of a cellular phone  130  that works together with a Bluetooth headset  110  to enable hands-free operation during a telephone call. Specifically, this figure shows a Bluetooth headset  110  connected to a cellular phone  130  through a Bluetooth link  160 . The Bluetooth headset  110  includes a Bluetooth audio decoder  112 , a Bluetooth audio encoder  115 , a Bluetooth flow/rate control logic  118 , a Bluetooth modem and radio module  120 , a speaker  122 , and a microphone  125 . The cellular phone  130  enables a near-end user to make and receive telephone calls to or from a far-end user over a VoLTE link  165 . The cellular phone  130  includes a Bluetooth modem and radio module  132 , a Bluetooth audio encoder  135 , a Bluetooth audio decoder  138 , an audio processing unit  140 , a Bluetooth flow/rate control logic  142 , an Adaptive Multi-Rate (AMR) audio decoder  145 , an AMR audio encoder  148 , a cellular flow/rate control logic  152 , and a baseband radio and modem  150 . 
     During a telephone call, the baseband radio and modem  150  of the cellular phone  130  receives downlink cellular packets from the far-end user through the VoLTE link  165 . The downlink cellular packets contain a downlink audio signal that is encoded with a speech coding standard such as adaptive multi-rate wideband (AMR-WB) for transmission over the VoLTE link  165 . The baseband radio and modem  150  sends the cellular packets to the AMR audio decoder  145 . The AMR audio decoder  145  decodes the cellular packets into an audio stream and sends the stream to the audio processing unit  140 . The audio processing unit  140  processes the stream to enhance audio quality and sends the processed stream to the Bluetooth audio encoder  135 . The Bluetooth audio encoder  135  encodes the processed stream into Bluetooth packets based on an audio subband codec such as high-efficiency advanced audio coding (HE-AAC) or low complexity subband coding (SBC). The Bluetooth audio encoder  135  sends the Bluetooth packets to the Bluetooth modem and radio module  132 , which then transmits the Bluetooth packets to via the Bluetooth link  160 . The Bluetooth flow/rate control logic  142  manages the rate of data transmission from the mobile device  130  to the Bluetooth headset  110  by controlling the encoding of Bluetooth packets at the Bluetooth audio encoder  135 . 
     The Bluetooth modem and radio module  120  of the Bluetooth headset  110  receives the Bluetooth packets from the cellular phone  130  through the Bluetooth link  160 . The Bluetooth modem and radio module  120  then sends the Bluetooth packets to the Bluetooth audio decoder  112 , which decodes the Bluetooth packets into an audio signal stream. The speaker  122  receives the audio signal stream and converts it into sound for the user of the Bluetooth headset  110 . 
     The microphone  125  of the Bluetooth headset  110  produces an uplink audio signal stream. The Bluetooth audio encoder  115  encodes the uplink audio signal into Bluetooth packets. The Bluetooth flow/rate control logic  118  manages the rate of data transmission from the Bluetooth headset  110  to the cellular phone  130  by controlling the encoding of Bluetooth packets at the Bluetooth audio encoder  115 . The Bluetooth modem and radio module  120  receives the Bluetooth packets from the Bluetooth audio encoder  115  and transmits them via the Bluetooth link  160 . 
     The local modem and radio module  132  of the cellular phone  130  receives the Bluetooth packets from the Bluetooth headset  110  through the Bluetooth link  160 . The local modem and radio module  132  then sends the Bluetooth packets to the Bluetooth audio decoder  138 , which decodes the Bluetooth packets into an audio signal stream. The audio processing unit  140  may process the audio signal stream to enhance audio quality and send the processed audio signal stream to the AMR audio encoder  148 . The AMR audio encoder  148  encodes the processed audio signal stream into uplink cellular packets and sends the uplink cellular packets to the baseband radio and modem  150 . The uplink cellular packets contain the uplink audio signal that is encoded with a speech coding standard such as adaptive multi-rate wideband (AMR-WB) for transmission over the VoLTE link  165 . The cellular flow/rate control logic  152  manages the rate of data transmission from the cellular phone  130  to the VoLTE link  165  by controlling the encoding of cellular packets at the AMR audio encoder  148 . The baseband radio and modem  150  sends the uplink cellular packets to the device of the far-end user through the VoLTE link  165 . 
     As illustrated in  FIG. 1 , during a telephone call, the incoming or downlink audio packets are decoded by the AMR audio decoder  145  and then encoded by the Bluetooth audio encoder  135  at the cellular phone  130 , and then decoded by the Bluetooth audio decoder  112  at the Bluetooth headset  110 . During the same telephone call, the outgoing or uplink audio packets are encoded by the Bluetooth audio encoder  115  at the Bluetooth headset  110 , and then decoded by the Bluetooth audio decoder  138  and encoded by the AMR audio encoder  148  at the cellular phone  130 . The flow control and buffering is done at multiple places, e.g., by the Bluetooth flow/rate control logic  118  at the Bluetooth headset  110 , and the Bluetooth flow/rate control logic  142  and cellular flow/rate control logic  152  at the cellular phone  130 . 
     SUMMARY 
     A headset that communicates with a mobile device through a local radio frequency (RF) communication link to conduct a telephone call is described. The headset includes a local RF communication modem that receives downlink packets from the mobile device through the local RF communication link. The downlink packets were received by the mobile device through a wireless communication link (e.g., from a cellular network base station, a wireless network access point, or a WiMAX gateway device). The headset further includes an audio decoder that decodes the downlink packets into a downlink audio signal to be converted into sound by a speaker at the headset. The headset also includes an audio encoder that encodes an uplink audio signal, produced using a microphone in the headset, into uplink packets. The local RF communication modem sends the uplink packets to the mobile device via the local RF communication link. The uplink packets will be transmitted by the mobile device over the wireless communication link. 
     In one embodiment, the downlink and uplink packets are encapsulated inside local RF packets when transmitted over the local RF communication link. In one embodiment, the headset includes a composite flow control logic that controls a first data transmission rate for transmitting data from the headset to the mobile device over the local RF communication link, a second data transmission rate for transmitting data from the mobile device to the headset over the local RF communication link, and a third data transmission rate for transmitting data from the mobile device to a far-end user&#39;s device over the wireless communication link. In one embodiment, the headset includes a call setup logic that performs continuous voice activity detection. The call setup logic includes a phrase identification logic that identifies phrases uttered by a user. 
     A method for a headset to communicate with a mobile device through a local RF communication link to conduct a telephone call is described. The method receives downlink packets from the mobile device through the local RF communication link. The method decodes the downlink packets into a downlink audio signal. The method processes the downlink audio signal and converts the processed downlink audio signal into sound through a speaker of the headset. The method produces an uplink audio signal through a microphone of the headset. The method encodes the uplink audio signal into uplink packets. The method sends the uplink packets to the mobile device through the local RF communication link. 
     An electronic device that communicates with a headset through a local RF communication link to conduct a telephone call is described. The electronic device includes a cellular communication modem that receives downlink cellular packets from a far-end user through a cellular communication link. The electronic device includes a local RF communication modem that sends the received downlink cellular packets to the headset without performing audio decoding upon them, and receives uplink cellular packets from the headset through the local RF communication link. The cellular communication modem sends out the uplink cellular packets to the far-end user through the cellular communication link without performing audio encoding upon them. 
     In one embodiment, the electronic device includes a local flow control logic that controls a rate of sending the downlink cellular packets by the local RF communication modem. The electronic device also includes a baseband flow control logic that controls a rate of sending the uplink cellular packets by the cellular communication modem. The local flow control logic and the baseband flow control logic are controlled by a composite flow control logic at the headset. 
     A method for an electronic device to communicate with a headset through a wireless connection to conduct a telephone call is described. The method receives downlink cellular packets from a cellular communication network through a cellular communication modem. A downlink audio signal was audio encoded in the downlink cellular packets by the cellular communication network. The method sends the downlink cellular packets to the headset through the wireless connection without audio decoding to extract the downlink audio signal. The method also receives uplink cellular packets from the headset through the wireless connection. An uplink audio signal was audio encoded in the uplink cellular packets by the headset, for transmission over the cellular communication network. The method sends the uplink cellular packets to the cellular communication network through the cellular communication modem without audio encoding of the uplink audio signal. 
     The above summary does not include an exhaustive list of all aspects of the invention. It is contemplated that the invention includes all systems and methods that can be practiced from all suitable combinations of the various aspects summarized above, as well as those disclosed in the Detailed Description below and particularly pointed out in the claims filed with the application. Such combinations have particular advantages not specifically recited in the above summary. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention is illustrated by way of example and not limitation in the figures of the accompanying drawings in which like references indicate similar elements. 
         FIG. 1  illustrates a detailed diagram of a mobile device that works together with a headset to enable hands-free operation during a telephone call. 
         FIG. 2  illustrates a user using a headset system in accordance with one embodiment of the invention. 
         FIG. 3  illustrates a detailed diagram of a headset system that performs cellular packet audio encoding and decoding at the headset during a telephone call in accordance with one embodiment of the invention. 
         FIG. 4  illustrates a detailed diagram of a headset system that that performs cellular packet audio encoding and decoding at the headset with composite flow control in accordance with one embodiment of the invention. 
         FIG. 5  illustrates a detailed diagram of a headset system that enables different call setup approaches by performing cellular packet audio encoding and decoding at the headset in accordance with one embodiment of the invention. 
         FIG. 6  illustrates a flowchart of operations performed in a mobile device in accordance with one embodiment of the invention. 
         FIG. 7  illustrates a flowchart of one embodiment of operations performed in a headset device in accordance with one embodiment of the invention. 
         FIG. 8  shows an example of a data processing system which may be used with one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     A headset system that enables cellular packets sent or received at a mobile device to be encoded or decoded by a headset working in concert with the mobile device, while eliminating cellular audio decoding and cellular audio encoding at the mobile device, is described. In the following description, numerous specific details are set forth to provide thorough explanation of embodiments of the invention. It will be apparent, however, to one skilled in the art, that embodiments of the invention may be practiced without these specific details. In other instances, well-known components, structures, and techniques have not been shown in detail in order not to obscure the understanding of this description. 
     Reference in the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification do not necessarily all refer to the same embodiment. 
     In the following description and claims, the terms “coupled” and “connected,” along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. “Coupled” is used to indicate that two or more elements, which may or may not be in direct physical or electrical contact with each other, co-operate or interact with each other. “Connected” is used to indicate the establishment of communication between two or more elements that are coupled with each other. 
     The processes depicted in the figures that follow are performed by processing logic that comprises hardware (e.g., circuitry, dedicated logic, etc.), software (such as is run on a general-purpose device or a dedicated machine), or a combination of both. Although the processes are described below in terms of some sequential operations, it should be appreciated that some of the operations described may be performed in different order. Moreover, some operations may be performed in parallel rather than sequentially. 
     Encoding and decoding of an audio signal is a nonlinear process, especially when using a parametric coding algorithm. There is significant quality degradation each time an audio signal is encoded and then decoded, especially when tandem encoding and decoding are performed with different codecs that have vastly different encoding schemes, as described in  FIG. 1  above. 
     There is also large audio latency in the system of  FIG. 1  above. For example, at the baseband modem  150 , delays are introduced in order to wait for the decoder/encoder to be ready. After decoding, buffering has to be performed before and after Inter-IC Sound (I 2 S) interface, and at the audio processing unit  140 . Delays are also introduced by Bluetooth encoding and decoding. Furthermore, because there are two or more flow/rate control logic modules working in isolation, these flow/rate control logic modules increase latency as well as jitter. This degrades audio communication quality. 
     An embodiment of the invention is a headset system in which cellular packets sent or received at a mobile device are audio encoded and/or audio decoded by a headset, while eliminating audio decoding and/or audio encoding of cellular packets at the mobile device. This headset system may improve uplink and/or downlink audio quality during a telephone call by having only one audio signal encoding/decoding stage. Encoding/decoding delays and packet level buffering are also reduced. Furthermore, by moving the audio encoding and/or audio decoding of cellular packets to the headset, an operating point of the voice encoder can be changed based on the combined radio frequency (RF) channel conditions of the cellular communication link and the short-range (or local RF) communication link, thus improving flow control with signal encoding/decoding. An encoder operating point is used to control the encoding rate of encoder that results in different average data rates. 
       FIG. 2  illustrates a user using a headset system in accordance with one embodiment of the invention. Specifically, the user in the figure is using a wireless headset  210  and is holding a mobile device  220  to participate in a telephone conversation. The headset  210  is a headphone combined with a microphone, or it may be a pair of headphones with a microphone, or any personal listening electronic device that can provide the equivalent functionality of a telephone handset but with hands-free operation. The mobile device  220  can be a cellphone, a smartphone, a tablet computer, a personal digital assistant (PDA), a laptop computer, a device equipped on a vehicle, a boat, or a bicycle, and which is capable of receiving and sending cellular network communications signals, e.g., from and to a cellular network base station, or any personal electronic device that is capable of receiving and sending cellular network communications signals. The headset  210  and the mobile device  220  work together to enable the user to have both hands free during the telephone conversation with a far-end user over the cellular communication network. 
     In one embodiment, the mobile device  220  receives downlink cellular packets from the cellular communication network and forwards the downlink cellular packets to the headset  210  through a local short-range communication link. The downlink cellular packets contain a downlink audio signal that is encoded in accordance with a speech coding algorithm such as adaptive multi-rate wideband (AMR-WB) suitable for transmission over a cellular communication network. The headset  210  receives the downlink cellular packets, and decodes them into a downlink audio signal to be converted into sound by a speaker in the headset  210 . When the near-end user speaks, one or more microphones of the headset  210  pick up the near-user&#39;s voice and produce an uplink audio signal based on it. The uplink audio signal is then encoded into uplink cellular packets at the headset  210 , using a speech coding algorithm such as adaptive multi-rate wideband (AMR-WB) suitable for transmission over the cellular communication network. The headset sends the uplink cellular packets to the mobile device  220 , which in turn sends the uplink cellular packets to the far-end user of the telephone conversation through the cellular communication network. The mobile device  220  does not need to audio decode or audio encode the cellular packets. 
       FIG. 3  illustrates a detailed diagram of a headset system that performs cellular packet audio encoding and decoding at the headset during a telephone call in accordance with one embodiment of the invention. A wireless headset  310  is connected to a mobile device  330  through a local RF communication link  360 . In one embodiment, the local RF communication link  360  is a short-range communication channel, e.g., Wi-Fi or Bluetooth. The wireless headset  310  includes a cellular packet audio decoder  312 , a cellular packet audio encoder  315 , a local modem and radio module  320 , a speaker  122 , and a microphone  125 . In one embodiment, the wireless headset  310  is the headset  210  described in  FIG. 2  above. The mobile device  330  enables a near-end user of the wireless headset  310  to make and receive telephone calls with a far-end user over a cellular communication link  365 . The cellular communication link  365  could be of 2G, 3G connection (GSM, UMTS, CDMA, CDMA2000), or LTE packet connection. Encoded audio packets are packaged inside this communications channel in the form of AMR, AMR-WB, or Enhance Variable Rate Codec (EVRC). The mobile device  330  includes a local modem and radio module  332  and a baseband radio and modem  350 . In one embodiment, the mobile device is the mobile device  220  described in  FIG. 2  above. The local modem and radio modules  320  and  332  use a wireless communication protocol, e.g., Bluetooth and Wi-Fi, to communication with each other. 
     The local modem and radio module  320  of the wireless headset  310  sends and receives cellular packets to and from the mobile device  330  over the local RF communication link  360 . In one embodiment, the cellular packets are encapsulated inside the data packets for the local RF communication protocol. The cellular packet audio decoder  312  receives downlink cellular packets from the local modem and radio module  320  and decodes the downlink cellular packets into a downlink audio signal, in accordance with an audio decoding algorithm that is the complement of the audio encoding algorithm applied by the cellular network to the downlink signal. The audio processing unit  318  receives the downlink audio signal from the cellular packet audio decoder  312 , processes the downlink audio signal, and sends the processed downlink audio signal to the speaker  122  to be converted into sound. The audio processing unit  318  also receives an uplink audio signal produced by microphone  125 , processes the uplink audio signal, and sends the processed uplink audio signal to the cellular packet audio encoder  315 . In one embodiment, the audio processing unit  318  performs one or more operations (e.g., equalization, dynamic range control, noise reduction, and automatic gain control) to enhance intelligibility of speech by the near end and far-end users. The cellular packet audio encoder  315  encodes the uplink audio signal into uplink cellular packets in accordance with an audio encoding algorithm that is the complement of the audio decoding algorithm which will be applied by the cellular network to the encoded uplink packets. The uplink cellular packets are sent to the local modem and radio module  320 , which in turn sends the uplink cellular packets to the mobile device  330  over the local RF communication link  360 . 
     The baseband radio and modem  350  of the mobile device  330  sends and receives cellular packets to and from the far-end user through the cellular communication link  365 . The baseband radio and modem  350  forwards the received cellular packets to the local modem and radio module  332  without audio decoding them, which sends the cellular packets to the wireless headset  310  over the local RF communication link  360 . The baseband radio and modem  350  also receives cellular packets from the local modem and radio module  332 , which received the cellular packets from the wireless headset  310  through the local RF communication link  360  and sends them to the network without audio encoding them for transmission over the cellular network. 
     During a telephone call, the baseband radio and modem  350  of the mobile device  330  receives downlink cellular packets from the far-end user through the cellular communication link  365 . The baseband radio and modem  350  sends the downlink cellular packets to the local modem and radio module  332 . The local modem and radio module  332  sends the downlink cellular packets to the wireless headset  310  through the local RF communication link  360 . 
     The local modem and radio module  320  of the wireless headset  310  receives the downlink cellular packets from the mobile device  330  through the local RF communication link  360 . The local modem and radio module  320  then sends the downlink cellular packets to the cellular packet audio decoder  312 , which decodes the downlink cellular packets into a downlink audio signal. The audio processing unit  318  receives the downlink audio signal, processes it, and sends the processed audio signal to the speaker  122 . The speaker  122  converts the downlink audio signal into sound for the user of the wireless headset  310  to hear. 
     The microphone  125  of the wireless headset  310  produces an uplink audio signal and sends the uplink audio signal to the audio processing unit  318 . The audio processing unit  318  receives the uplink audio signal, processes it, and sends the processed uplink audio signal to the cellular packet audio encoder  315 . The cellular packet audio encoder  315  encodes the uplink audio signal into uplink cellular packets. The local modem and radio module  320  receives the uplink cellular packets from the cellular packet audio encoder  315  and sends the uplink cellular packets to the mobile device  330  over the local RF communication link  360 . 
     The local modem and radio module  332  of the mobile device  330  receives the uplink cellular packets from the wireless headset  310  through the local RF communication link  360 . The local modem and radio module  332  then sends the uplink cellular packets to the baseband radio and modem  350 , which in turn sends the uplink cellular packets to the device of the far-end user through the cellular communication link  365 . 
     As illustrated in  FIG. 3 , during a telephone call, the incoming/downlink audio signal is decoded by the cellular packet audio decoder  312  at the wireless headset  310 . During the same telephone call, the outgoing/uplink audio signal is encoded by the cellular packet audio encoder  315  at the wireless headset  310 . No encoding or decoding of the audio signals is performed at the mobile device  330 . Therefore, instead of having two stages of audio signal encoding and decoding as described in  FIG. 1  above, there is only a single stage of audio signal encoding and decoding. As a result, the audio quality of uplink and downlink audio signals may be improved, encoding and decoding delays may be reduced, and packet level buffering may also be reduced. In addition, raw pulse-code modulation (PCM) transport buffering (used for a decoded audio signal in the mobile device of  FIG. 1 ) may not be needed. 
     The embodiment described in  FIG. 3  refers to the use of cellular communication link by the mobile device  330  to receive and send from/to a cellular communication network, e.g., 2G, 3G, GSM, UMTS, CDMA, CDMA2000, 1× Advanced, VoLTE, In one embodiment, instead of receiving downlink audio signal and sending uplink audio signal through a cellular communication link, the mobile device  330  can receive downlink audio signal and send uplink audio signal through a Wi-Fi link, e.g., based on the IEEE 802.11 standards. In yet another embodiment, the mobile device  330  can receive downlink audio signal and send uplink audio signal through a WiMAX link, e.g., based on the IEEE 802.16 standards. In these alternative embodiments, the audio signal may be speech encoded with audio codecs such as Speex, SILK, Opus, G.711, internet Speech Audio Codec (iSAC), and Internet Low Bitrate Codec (iLBC). 
     The wireless headset  310  and the mobile device  330  are described above for one embodiment of the invention. One of ordinary skill in the art will realize that in other embodiments, this system can be implemented differently. For instance, in one embodiment described above, certain modules are implemented as software modules for example to be executed by an application processor or a system-on-chip (SoC). However, in another embodiment, some or all of the modules might be implemented by hardwired or programmable logic gates, which can be dedicated application specific hardware (e.g., an application specific integrated circuit, ASIC, chip or component) or a general purpose chip (e.g., a microprocessor or field programmable gate array, FPGA). 
       FIG. 4  illustrates a detailed diagram of a headset system that that performs cellular packet audio encoding and decoding at the headset with composite flow control in accordance with one embodiment of the invention. Specifically, this figure shows a headset  410  connected to a mobile device  430  through a local RF communication link  360 . The headset  410  is similar to the wireless headset  310  described in  FIG. 3  above. In one embodiment, in addition to the components of the wireless headset  310 , the headset  410  includes a composite flow/rate control logic  420 . The mobile device  430  is similar to the mobile device  330  described in  FIG. 3  above. In one embodiment, in addition to the components of the mobile device  330 , the mobile device  430  includes a packet jitter controller  435 , a local flow control logic  440 , and a baseband flow/rate control logic  445 . 
     The composite flow/rate control logic  420  of the headset  410  manages packet flow for the local RF communication link  360  and the cellular communication link  365 , as well as encoder operating point of the cellular packet audio encoder  315 . Through a local flow control data interchange  450 , the composite flow/rate control logic  420  exchanges information with the local flow control logic  440  and baseband flow/rate control logic  445 . Therefore, the composite flow/rate control logic  420  controls packet flow for both the local RF communication link  360  and the cellular communication link  365 . In one embodiment, the composite flow/rate control logic  420  receives information about the cellular communication link  365  from the baseband flow/rate control logic  445 , and receives information about the local RF communication link  360  from the local flow control logic  440 . The local flow control logic  440  manages the rate of data transmission from the mobile device  430  to the headset  410  based on parameters received from the composite flow/rate control logic  420 . The baseband flow/rate control logic  445  manages the rate of data transmission from the mobile device  430  to the device of the far-end user over the cellular communication link  365  based on parameters received from the composite flow/rate control logic  420 . In one embodiment, the baseband flow/rate control logic  445  connects to the composite flow/rate control logic  420  through the local flow control logic  440 . In another embodiment, the baseband flow/rate control logic  445  connects to the composite flow/rate control logic  420  directly. 
     The local flow control data interchange  450  is conducted over the local RF communication link  360 . In one embodiment, the flow control data is transmitted as a section in the regular data packet for the local RF communication link  360 . In another embodiment, the flow control data is transmitted through special flow control packets over the local RF communication link  360 . The packet jitter controller  435  handles local retransmissions of the packets. In one embodiment, the packet jitter controller  435  can optionally open up a cellular packet and fix errors in it. 
     During a telephone call, the baseband radio and modem  350  of the mobile device  430  receives downlink cellular packets from the far-end user through the cellular communication link  365 . The baseband radio and modem  350  sends the downlink cellular packets to the local modem and radio module  332  by passing through the packet jitter controller  435 . The local modem and radio module  332  sends the downlink cellular packets to the headset  410  through the local RF communication link  360 . The transmission rate of the downlink cellular packet over the local RF communication link  360  is controlled by the composite flow/rate control logic  420  through the local flow control logic  440 . 
     The local modem and radio module  320  of the headset  410  receives the downlink cellular packets from the mobile device  330  through the local RF communication link  360 . The local modem and radio module  320  then sends the downlink cellular packets to the cellular packet audio decoder  312 , which decodes the downlink cellular packets into a downlink audio signal. The audio processing unit  318  receives the downlink audio signal, processes it, and sends the processed audio signal to the speaker  122 . The speaker  122  plays back the downlink audio signal to the user of the headset  410 . 
     The microphone  125  of the headset  410  produces an uplink audio signal and sends it to the audio processing unit  318 . The audio processing unit  318  receives the uplink audio signal, processes it, and sends the processed uplink audio signal to the cellular packet audio encoder  315 . The cellular packet audio encoder  315  encodes the uplink audio signal into uplink cellular packets. The local modem and radio module  320  receives the uplink cellular packets from the cellular packet audio encoder  315  and sends the uplink cellular packets to the mobile device  430  over the local RF communication link  360 . The transmission rate of the uplink cellular packets over the local RF communication link  360  is controlled by the composite flow/rate control logic  420 . 
     The local modem and radio module  332  of the mobile device  430  receives the uplink cellular packets from the headset  410  through the local RF communication link  360 . The local modem and radio module  332  then sends the uplink cellular packets to the baseband radio and modem  350  by passing through the packet jitter controller  435 . The baseband radio and modem  350  in turn sends the uplink cellular packets to the device of the far-end user through the cellular communication link  365 . The transmission rate of the uplink cellular packets over the cellular communication link  365  is controlled by the composite flow/rate control logic  420  through the baseband flow/rate control logic  445 . 
     As illustrated in  FIG. 4 , during a telephone call, the incoming/downlink audio signal is decoded by the cellular packet audio decoder  312  at the headset  410 . During the same telephone call, the outgoing/uplink audio signal is encoded by the cellular packet audio encoder  315  at the headset  410 . No encoding or decoding of the audio signals is performed at the mobile device  430 . Therefore, instead of having two stages of audio signal encoding and decoding as described in  FIG. 1  above, there is only a single stage of audio signal encoding and decoding. As a result, the audio quality of uplink and downlink audio signals is improved. Encoding and decoding delays are reduced. Packet level buffering is also reduced. In addition, raw pulse-code modulation (PCM) transport buffering is not needed. 
     Because the composite flow/rate control logic  420  is used to manage packet flow for the local RF communication link  360  and the cellular communication link  365 , there is robust flow control with signal encoding and decoding. The encoder operating point of the cellular packet audio encoder  315  can be changed based on the conditions of both the cellular communication link  365  and the local RF communication link  360 . For example, if one of the cellular communication link  365  and the local RF communication link  360  has poor connection quality, the cellular packet audio encoder  315  can use a lower bit rate in encoding the uplink audio signal. If both the cellular communication link  365  and the local RF communication link  360  have excellent connection quality, the cellular packet audio encoder  315  can use a higher bit rate in encoding the uplink audio signal. 
     The headset  410  and the mobile device  430  are described above for one embodiment of the invention. One of ordinary skill in the art will realize that in other embodiments, this system can be implemented differently. For instance, in one embodiment described above, certain modules are implemented as software modules. However, in another embodiment, some or all of the modules might be implemented by hardware, which can be dedicated application specific hardware (e.g., an application specific integrated circuit, ASIC, chip or component) or a general purpose chip (e.g., a microprocessor or field programmable gate array, FPGA). 
       FIG. 5  illustrates a detailed diagram of a headset system that enables different call setup approaches by performing cellular packet audio encoding and decoding at the headset in accordance with one embodiment of the invention. Specifically, this figure shows a headset  510  connected to a mobile device  530  through a local RF communication link  360 . In one embodiment, the headset system also includes an additional device  550 . The device  550  includes a call setup/pick logic  555 . 
     In one embodiment, the headset  510  is similar to the wireless headset  310  described in  FIG. 3  above. In another embodiment, the headset  510  is similar to the headset  410  described in  FIG. 4  above. In one embodiment, in addition to the components of the wireless headset  310  or headset  410 , the headset  510  includes a call setup/pick logic  515 . In one embodiment, the mobile device  530  is similar to the mobile device  330  described in  FIG. 3  above. In another embodiment, the mobile device  530  is similar to the mobile device  430  described in  FIG. 4  above. In one embodiment, in addition to the components of the mobile device  330  or mobile device  430 , the mobile device  430  includes a call setup/pick logic  535 . 
     Because the encoding and decoding of the cellular packets is at the headset  510 , packets from any cellular modem can be used in this headset system. Therefore, the mobile device  530  can be a cellphone, a smartphone, a tablet computer, a PDA, a laptop computer, a device equipped on a vehicle, a boat, or a bicycle and capable of receiving and sending cellular packets, or any personal electronic device that is capable of receiving and sending cellular packets. 
     In one embodiment, the call setup/pick logic  515  of the headset  510  can perform continuous voice activity detection with a phrase identification logic (not shown) to enable hands-free operations, e.g., initiating or ending a telephone call. The phrase identification logic runs continuously and can identify short phrases such as “call home” and “pickup”. Once the call setup/pick logic  515  detects a voice command related to setting up or picking up a telephone call, the call setup/pick logic  515  can communicate to the mobile device  530  to enable/establish the call and route cellular packets to the headset  510 . 
     The call setup/pick logic  535  of the mobile device  530  enables a user to set up or pick up a telephone call, e.g., by pressing a button or key at the mobile device  530 . As discussed above, the mobile device  530  can be a full-function cellphone/smartphone, a device equipped on a vehicle, a boat, or a bicycle and capable of receiving and sending cellular packets, or just a personal electronic device capable of routing cellular packets to the headset  510 . 
     In one embodiment, the device  550  is a separate electronic device, e.g., eye glasses, that is capable of performing certain functions that may or may not relate to telephone calls. The call setup/pick logic  555  of the device  550  can detect user commands of setting up or picking up a telephone call through, e.g., eye tracking or camera based technology. Once the call setup/pick logic  555  detects a user command related to setting up or picking up a telephone call, the call setup/pick logic  555  can communicate to the mobile device  530  to enable/establish the call and route cellular packets to the headset  510 . 
     Even though the call setup/pick logics  515 ,  535 , and  555  are all described in the embodiment in  FIG. 5 , one of ordinary skill in the art will recognize that in other embodiments, this system can be implemented differently, e.g., by having one or two of the call setup/pick logics  515 ,  535 , and  555  in the system. The device  550  is optional. In one embodiment, the functionality of the device  550  can be incorporated into either the headset  510  or the mobile device  530 . In one embodiment, the functionality of the mobile device  530  can be incorporated into the headset  510 . As a result, the headset  510  can be used by a near-end user to conduct a telephone call with a far-end user without the assistance of any other device. 
     The headset  510 , the mobile device  530 , and the device  550  are described above for one embodiment of the invention. One of ordinary skill in the art will realize that in other embodiments, this system can be implemented differently. For instance, in one embodiment described above, certain modules are implemented as software modules. However, in another embodiment, some or all of the modules might be implemented by hardware, which can be dedicated application specific hardware (e.g., an application specific integrated circuit, ASIC, chip or component) or a general purpose chip (e.g., a microprocessor or field programmable gate array, FPGA). 
       FIG. 6  illustrates a flowchart of operations performed in a mobile device, referred to as process  600 . In one embodiment, the mobile device (e.g., the mobile device  220  of  FIG. 2 , the mobile device  330  of  FIG. 3 , the mobile device  430  of  FIG. 4 , or the mobile device  530  of  FIG. 5 ) executes process  600  when a telephone call is initiated. As illustrated in  FIG. 6 , process  600  begins by receiving (at block  605 ) downlink cellular packets from a cellular communication network through a cellular communication modem. A downlink audio signal is encoded in the downlink cellular packets. The cellular communication network could be of 2G, 3G network (GSM, UMTS, CDMA, CDMA2000), or LTE network. Encoded audio packets are packaged inside this communications channel in the form of AMR, AMR-WB, or Enhance Variable Rate Codec (EVRC). 
     At block  610 , process  600  sends the downlink cellular packets to a headset device (e.g., the headset  210  of  FIG. 2 , the wireless headset  310  of  FIG. 3 , the headset  410  of  FIG. 4 , or the headset  510  of  FIG. 5 ) through a wireless connection without decoding the downlink audio signal. In one embodiment, the wireless connection is established over a short-range radio communication channel, e.g., Wi-Fi or Bluetooth. 
     At block  615 , process  600  receives uplink cellular packets from the headset device through the wireless connection. An uplink audio signal is encoded in the uplink cellular packets. At block  620 , process  600  sends the uplink cellular packets to the cellular communication network through the cellular communication modem without encoding the uplink audio signal. 
     In one embodiment, the transmission rate of sending the downlink cellular packets to the headset device over the wireless connection is controlled by a local flow control logic of the mobile device. The transmission rate of sending the uplink cellular packets to the cellular communication network through the cellular communication modem is controlled by a baseband flow/rate control logic of the mobile device. In one embodiment, the local flow control logic sends information about the wireless connection to a composite flow/rate control logic of the headset device and receives parameters from the composite flow/rate control logic. The local flow control logic uses the parameters received from the composite flow/rate control logic to control the transmission rate of sending the downlink cellular packets to the headset device over the wireless connection. In one embodiment, the baseband flow/rate control logic sends information about the cellular communication network to the composite flow/rate control logic of the headset device and receives parameters from the composite flow/rate control logic. The baseband flow/rate control logic uses the parameters received from the composite flow/rate control logic to control the transmission rate of sending the uplink cellular packets to the cellular communication network through the cellular communication modem. 
     One of ordinary skill in the art will recognize that process  600  is a conceptual representation of the operations executed by the mobile device to route cellular packets to and from the headset device without decoding or encoding the cellular packets. The specific operations of process  600  may not be performed in the exact order shown and described. The specific operations may not be performed in one continuous series of operations, and different specific operations may be performed in different embodiments. For example, the operations in blocks  615  and  620  may be performed prior to, or in parallel with the operations in blocks  605  and  610 . Furthermore, process  600  could be implemented using several sub-processes, or as part of a larger macro process. 
     The embodiment described in  FIG. 6  refers to the use of cellular communication modem of the mobile device to receive and send from/to a cellular communication network, e.g., 2G, 3G, GSM, UMTS, CDMA, CDMA2000, 1× Advanced, VoLTE, In one embodiment, instead of receiving downlink audio signal and sending uplink audio signal from/to a cellular communication network through a cellular communication modem, the mobile device can receive downlink audio signal and send uplink audio signal through a Wi-Fi link, e.g., based on the IEEE 802.11 standards. In yet another embodiment, the mobile device can receive downlink audio signal and send uplink audio signal through a WiMAX link, e.g., based on the IEEE 802.16 standards. In these alternative embodiments, the audio signal may be speech encoded with audio codecs such as Speex, SILK, Opus, G.711, internet Speech Audio Codec (iSAC), and Internet Low Bitrate Codec (iLBC). 
       FIG. 7  illustrates a flowchart of one embodiment of operations performed in a headset device, referred to as process  700 . In one embodiment, the headset device (e.g., the headset  210  of  FIG. 2 , the wireless headset  310  of  FIG. 3 , the headset  410  of  FIG. 4 , or the headset  510  of  FIG. 5 ) executes process  700  when a telephone call is initiated. In one embodiment, the operations of process  700  are performed in concert with the operations of process  600  described in  FIG. 6  above. As illustrated in  FIG. 7 , process  700  begins by receiving (at block  705 ) downlink cellular packets from a mobile device through a wireless connection. In one embodiment, the mobile device executes the operations of process  600  described in  FIG. 6  above, and the downlink cellular packets are the downlink cellular packets described in blocks  605  and  610  of process  600 . 
     At block  710 , process  700  decodes the downlink cellular packets into a downlink audio signal. At block  715 , process  700  converts the downlink audio signal into sound through a speaker of the headset device. 
     At block  720 , process  700  produces an uplink audio signal through one or more microphones of the headset device. At block  725 , process  700  encodes the uplink audio signal into uplink cellular packets. At block  730 , process  700  sends the uplink cellular packets to the mobile device through the wireless connection. In one embodiment, the mobile device executes the operations of process  600  described in  FIG. 6  above, and the uplink cellular packets are the uplink cellular packets described in blocks  615  and  620  of process  600 . 
     In one embodiment, the transmission rate of sending the uplink cellular packets to the mobile device over the wireless connection by the headset device is controlled by a composite flow/rate control logic of the headset device. In one embodiment, the composite flow/rate control logic of the headset device receives information about the wireless connection and the cellular communication network from local flow control logics of the mobile device. In one embodiment, the composite flow/rate control logic of the headset device sends parameters to the local flow control logics of the mobile device to control the transmission rate of sending the downlink cellular packets to the headset device by the mobile device. In one embodiment, the composite flow/rate control logic sends parameters to the local flow control logics of the mobile device to control the transmission rate of sending the uplink cellular packets to the cellular communication network by the mobile device. 
     One of ordinary skill in the art will recognize that process  700  is a conceptual representation of the operations executed by the headset device. The specific operations of process  700  may not be performed in the exact order shown and described. The specific operations may not be performed in one continuous series of operations, and different specific operations may be performed in different embodiments. For example, the operations in blocks  720 ,  725 , and  730  may be performed prior to, or in parallel with the operations in blocks  705 ,  710 , and  715 . Furthermore, process  700  could be implemented using several sub-processes, or as part of a larger macro process. 
       FIG. 8  shows an example of a data processing system  800  which may be used with one embodiment of the invention. Specifically, this figure shows a data processing system  800 . The data processing system  800  shown in  FIG. 8  includes a processing system  811 , which may be one or more microprocessors or a system on a chip integrated circuit. The data processing system  800  also includes memory  801  for storing data and programs for execution by the processing system  811 . The data processing system  800  also includes an audio input/output subsystem  805 , which may include a primary microphone  865 , a secondary microphone  860 , and a speaker  855 , for example, for playing back music or providing telephone functionality through the speaker and microphones. 
     A display controller and display device  809  provide a digital visual user interface for the user; this digital interface may include a graphical user interface similar to that shown on a Macintosh computer when running the OS X operating system software, or an Apple iPhone when running the iOS operating system, etc. The system  800  also includes one or more wireless communications interfaces  803  to communicate with another data processing system, such as the system  800  of  FIG. 8 . A wireless communications interface may be a WLAN transceiver, an infrared transceiver, a Bluetooth transceiver, and/or a cellular telephony transceiver. It will be appreciated that additional components, not shown, may also be part of the system  800  in certain embodiments, and in certain embodiments fewer components than shown in  FIG. 8  may also be used in a data processing system. The system  800  further includes one or more wired power and communications interfaces  817  to communicate with another data processing system. The wired power and communications interface may be a USB port, etc. and may connect to a battery  818 . 
     The data processing system  800  also includes one or more user input devices  813 , which allow a user to provide input to the system. These input devices may be a keypad or keyboard, or a touch panel or multi touch panel. The data processing system  800  also includes an optional input/output device  815  which may be a connector for a dock. It will be appreciated that one or more buses, not shown, may be used to interconnect the various components as is well known in the art. The data processing system shown in  FIG. 8  may be a handheld device or a personal digital assistant (PDA), or a cellular telephone with PDA-like functionality, or a handheld device which includes a cellular telephone, or a media player such as an iPod, or a device which combines aspects or functions of these devices such as a media player combined with a PDA and a cellular telephone in one device or an embedded device or other consumer electronic devices. In other embodiments, the data processing system  800  may be a network computer or an embedded processing device within another device or other type of data processing systems, which have fewer components or perhaps more components than that shown in  FIG. 8 . 
     The digital signal processing operations described above, such as encoding and decoding of cellular packets, flow/rate control, packet jitter control, setup or pickup of telephone call, and the audio signal processing including for example filtering, noise estimation, and noise suppression, can all be done either entirely by a programmed processor, or portions of them can be separated out and be performed by dedicated hardwired logic circuits. 
     The foregoing discussion merely describes some exemplary embodiments of the invention. One skilled in the art will readily recognize from such discussion, from the accompanying drawings, and from the claims that various modifications can be made without departing from the spirit and scope of the invention.

Metadata:
Filing Date: 20140220
Publication Date: 20170207
Grant Date: 20170207
Priority Date: 20140220
Inventors: THEVERAPPERUMA LALIN S.
PAQUIER BAPTISTE P.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W76/023", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W4/008", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04M1/6066", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04M1/6066", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04M1/6066", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W4/80", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W4/80", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 53799220