PATENT DOCUMENT

Publication Number: US-11139924-B2
Application Number: US-202016820581-A
Country: US
Kind Code: B2

Title: Method and system to improve link budget of a wireless system

Abstract:
A method and system to improve the link budget of a wireless system using fast Hybrid Automatic Repeat Request (HARQ) protocol. In one embodiment of the invention, the Medium Access Control (MAC) logic in a base station determines whether the quality of the communication link with a mobile station is bad. When the MAC logic in the base station determines that the quality is bad, the base station uses a fast Hybrid Automatic Repeat Request (HARQ) protocol to indicate to the mobile station to send identical information to the base station in each of a plurality of successive or consecutive communication intervals before processing any received identical information from the mobile station. The fast HARQ protocol reduces the latency of receiving the identical information correctly, as compared with the current HARQ protocol.

Claims:
What is claimed is: 
     
       1. A base station in a wireless communication network, the base station comprising:
 one or more processors and one or more storage devices storing instructions that are operable, when executed by the one or more processors, to cause the one or more processors to perform operations comprising:
 determining a parameter associated with a communication link with a mobile station; 
 determining, based on the parameter, a repetition factor for a repetition coding scheme; and 
 transmitting a request to the mobile station to send identical information to the base station in each of a number of successive communication intervals, wherein the number is based on the repetition factor. 
 
 
     
     
       2. The base station of  claim 1 , wherein the parameter associated with the communication link is a quality of the communication link, and wherein the operations further comprise:
 determining that the quality of the communication link is less than a threshold quality. 
 
     
     
       3. The base station of  claim 2 , where the quality of the communication link with the mobile station is based on at least one of channel quality information (CQI), or Hybrid Automatic Repeat Request (HARQ) acknowledgement (ACK) and negative ACK (NACK). 
     
     
       4. The base station of  claim 1 , wherein the parameter is a distance between the base station and the mobile station, and wherein the operations further comprise:
 determining that the distance is greater than a threshold distance. 
 
     
     
       5. The base station of  claim 1 , wherein transmitting the request to the mobile station comprises:
 sending the request to the mobile station in each of a number of consecutive frames. 
 
     
     
       6. The base station of  claim 1 , the operations further comprising:
 receiving, during a first interval, a first set of information from the mobile station; 
 determining not to process the first set of information; and 
 receiving, during a second interval, a second set of information from the mobile station. 
 
     
     
       7. The base station of  claim 6 , the operations further comprising:
 combining the first and second set of information; 
 calculating a cyclic redundancy code (CRC) of the combined information; and 
 determining, based on the CRC, to process the combined information. 
 
     
     
       8. A user equipment (UE) in a wireless communication network, the UE comprising:
 one or more processors and one or more storage devices storing instructions that are operable, when executed by the one or more processors, to cause the one or more processors to perform operations comprising:
 receiving from a base station a request to send identical information to the base station according to a repetition coding scheme, the repetition coding scheme generated in response to a quality of a communication link between the UE and the base station being less than a threshold; and 
 in response to receiving the request, using the repetition coding scheme to transmit to the base station the identical information in a particular information burst. 
 
 
     
     
       9. The UE of  claim 8 , wherein the particular information burst comprises a plurality of communication intervals. 
     
     
       10. The UE of  claim 9 , wherein a number of the plurality of communication intervals is based on the repetition coding scheme. 
     
     
       11. The UE of  claim 8 , wherein using the repetition coding scheme to transmit to the base station the identical information in the particular information burst comprises:
 transmitting to the base station in a first interval a first instance of the identical information; and 
 transmitting to the base station in a second interval a second instance of the identical information, wherein the second instance of the identical information is transmitted without waiting for feedback from the base station between the first and the second intervals. 
 
     
     
       12. The UE of  claim 8 , wherein the identical information comprises uplink data. 
     
     
       13. The UE of  claim 8 , wherein receiving from the base station the request comprises receiving the request from the base station in each of a number of consecutive frames. 
     
     
       14. A method performed by one or more device processors in a cellular communications network, the method comprising:
 determining a parameter associated with a communication link with a mobile station; 
 determining, based on the parameter, a repetition factor for a repetition coding scheme; and 
 transmitting a request to the mobile station to send identical information to a base station in each of a number of successive communication intervals, wherein the number is based on the repetition factor. 
 
     
     
       15. The method of  claim 14 , wherein the parameter associated with the communication link is a quality of the communication link, and wherein the method further comprises:
 determining that the quality of the communication link is less than a threshold quality. 
 
     
     
       16. The method of  claim 15 , where the quality of the communication link with the mobile station is based on at least one of channel quality information (CQI), or Hybrid Automatic Repeat Request (HARQ) acknowledgement (ACK) and negative ACK (NACK). 
     
     
       17. The method of  claim 14 , wherein the parameter is a distance between the base station and the mobile station, and wherein the method further comprises:
 determining that the distance is greater than a threshold distance. 
 
     
     
       18. The method of  claim 14 , wherein transmitting the request to the mobile station comprises:
 sending the request to the mobile station in each of a number of consecutive frames. 
 
     
     
       19. The method of  claim 14 , the method further comprising:
 receiving, during a first interval, a first set of information from the mobile station; 
 determining not to process the first set of information; and 
 receiving, during a second interval, a second set of information from the mobile station. 
 
     
     
       20. The method of  claim 19 , the method further comprising:
 combining the first and second set of information; 
 calculating a cyclic redundancy code (CRC) of the combined information; and 
 determining, based on the CRC, to process the combined information.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. application Ser. No. 15/864,809, filed Jan. 8, 2018, which is a continuation of U.S. application Ser. No. 15/144,510, filed May 2, 2016, entitled “METHOD AND SYSTEM TO IMPROVE LINK BUDGET OF A WIRELESS SYSTEM,” which is continuation of U.S. application Ser. No. 14/296,313, filed Jun. 4, 2014, entitled “METHOD AND SYSTEM TO IMPROVE LINK BUDGET OF A WIRELESS SYSTEM,” which is now U.S. Pat. No. 9,356,741, issued on May 31, 2016, which is a divisional of U.S. application Ser. No. 12/502,857, filed Jul. 14, 2009, entitled “METHOD AND SYSTEM TO IMPROVE LINK BUDGET OF A WIRELESS SYSTEM,” which is now U.S. Pat. No. 8,782,482, issued on Jul. 15, 2014; the entire disclosures of which are hereby incorporated by reference in their entireties. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to the field of wireless communication, and more specifically but not exclusively, to improve the link budget of a wireless system using fast hybrid automatic repeat request protocol. 
     BACKGROUND DESCRIPTION 
     In a wireless system, the receiving node typically needs to receive a minimum power level per tone of the transmitted information burst. A Hybrid Automatic Repeat Request (HARQ) protocol allows retransmission of the information burst by the transmitting node and combining the received information bursts in the receiving node to effectively increase the received power per tone. The transmitting node can gain about 3 decibels (dB) with the same power per tone by retransmitting the original information burst. If the information burst is retransmitted 3 times, i.e., a total of 4 transmissions of the same information burst, the transmitting node can gain about 6 dB compared to a single transmission of the information burst. 
       FIG. 1A  illustrates a prior art timeline  100  of the communication exchanges between a base station and a mobile station operating in accordance with HARQ. The prior art timeline  100  shows five frames  102 ,  104 ,  106 ,  108 , and  110 . In frame x  102 , the base station sends a HARQ uplink Medium Access Protocol Information Element (HARQ UL MAP IE)  120  to the mobile station. The HARQ UL MAP IE  120  indicates to the mobile station to send particular information to the base station. In frame x+1  104 , the mobile station sends a HARQ UL transmission (HARQ UL TX) burst  122  of the particular information to the base station in response to the HARQ UL MAP IE  120 . 
     The base station receives the HARQ UL TX burst  122  and processes it to check for any errors. The received HARQ UL TX burst  122  is assumed to have an error in this example and the base station sends another HARQ UL MAP IE  124  in frame x+3  108  to indicate to the mobile station to retransmit the particular information again. After receiving the UL MAP  124 , the mobile station sends a HARQ UL retransmission (HARQ UL reTX) burst  126  of the particular information to the base station in frame x+4  110 . 
     The time interval between HARQ UL TX burst  122  and HARQ UL reTX burst  126  is denoted as HARQ Round Trip Time (RTT)  132  and is assumed to be 3 frames for the purpose of illustration. The HARQ RTT is the minimum time between a transmission of a particular information burst and the retransmission of the particular information (or a new transmission of another information burst) in the same HARQ channel. 
     Repetition coding is another technique that can increase reliability of the transmission. For example, a repetition coding scheme with a repetition factor of two, repeats two times for each bit that is to be transmitted and the number of slots required for transmission is doubled as shown in  FIG. 1B . If the transmitting node is limited by the total power that it can transmit, repetition coding does not help in increasing the reliability of the transmission. This is because the power per tone needs to be halved in order to transmit twice as many tones, assuming that the transmission requires the maximum total power when no repetition coding is used. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The features and advantages of embodiments of the invention will become apparent from the following detailed description of the subject matter in which: 
         FIG. 1A  illustrates a prior art timeline of the communication exchanges between a base station and a mobile station operating in accordance with a hybrid automatic repeat request protocol; 
         FIG. 1B  illustrates a prior art channel allocation with and without repetition coding; 
         FIG. 2  illustrates a wireless system in accordance with one embodiment of the invention; 
         FIG. 3  illustrates a protocol structure of a node according to one embodiment of the invention; 
         FIG. 4  illustrates a timeline of the communication exchanges between a base station and a mobile station in accordance with one embodiment of the invention; 
         FIG. 5  illustrates a flow chart of the steps to improve the link budget of a wireless system in accordance with one embodiment of the invention; and 
         FIG. 6  illustrates a block diagram of a system to implement the methods disclosed herein according with one embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the invention described herein are illustrated by way of example and not by way of limitation in the accompanying figures. For simplicity and clarity of illustration, elements illustrated in the figures are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements for clarity. Further, where considered appropriate, reference numerals have been repeated among the figures to indicate corresponding or analogous elements. Reference in the specification to “one embodiment” or “an embodiment” of the invention means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrase “in one embodiment” in various places throughout the specification are not necessarily all referring to the same embodiment. 
     Embodiments of the invention provide a method and system to improve the link budget of a wireless system using fast HARQ. The fast HARQ is compliant at least in part, with the HARQ protocol. In one embodiment of the invention, the wireless system includes, but is not limited to, two or more nodes capable of exchanging information wirelessly. The node includes, but is not limited to, a base station, a mobile or remote station, a desktop computer, a laptop computer, a notebook computer, a netbook computer, a personal digital assistant (PDA), a server, a workstation, a cellular telephone, a mobile computing device, and the like. 
     In one embodiment of the invention, the nodes communicate using a communication standard that includes, but is not limited to, one of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 family of standards, 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) standard, High-Speed Downlink Packet Access (HSDPA) standard, or any other wired or wireless communication standard capable of implementing or using HARQ protocol. 
       FIG. 2  illustrates a wireless system  200  in accordance with one embodiment of the invention. For clarity of illustration, only one mobile station  210  and one base station  220  are shown in the wireless system  200 . The wireless system  200  may include more than one base station  220  and each base station  220  may support more than one mobile station  210 . 
     In one embodiment of the invention, the mobile station  210  has control logic  212  coupled with the medium access control (MAC) logic  214 . The control logic  212  allows the mobile station  210  to function as a wireless station in accordance with the wireless communication protocol(s) described herein. The MAC logic  214  controls the signaling between the mobile station  210  and the base station  220 , and also controls the physical (PHY) layer logic  216  that is coupled with antenna  218 . 
     In one embodiment of the invention, the base station  220  has control logic  222  coupled with the MAC logic  224 . The control logic  222  allows the base station  220  to function as a wireless station in accordance with the wireless communication protocol(s) described herein. It can also facilitate information exchanges between mobile stations connected with the base station  220 . The MAC logic  224  controls the signaling between the base station  220  and the mobile station  210 , and also controls the PHY layer logic  226  that is coupled with antenna  228 . The antennas  218  and  228  are communicating via a communication link or channel  230  that is wireless. The quality or reliability of the communication link  230  depends on one or more factors that include, but are not limited to, distance between the antennas  218  and  228 , interference from other devices or stations, multi-path loss, cross-talk, mobility of the mobile station, shadowing, multi-path fading, and the like. 
     In one embodiment of the invention, the MAC logic  224  in the base station  220  determines whether the quality of the communication link  230  with the mobile station  210  is bad. When the MAC logic  224  in the base station  220  determines that the quality is bad, the base station  220  uses a fast HARQ protocol to indicate to the mobile station  210  to send identical information to the base station  220  in each of a plurality of successive or consecutive communication intervals before processing any received identical information from the mobile station  210  in one embodiment of the invention. By using the fast HARQ protocol in one embodiment of the invention, the base station  220  uses less time to request a retransmission of a particular burst from the mobile station  210  as it does not need to wait for the processing time to determine that a retransmission of the particular burst is required. 
     The base station  220  can signal the mobile station  210  in a number of consecutive communication intervals to transmit identical information to the base station  220  before processing any received identical information from the mobile station  210 . A wireless system  200  that employs fast HARQ protocol can support traffic with lower latencies as the signaling time between the base station  220  and the mobile station  210  for retransmissions of information is reduced in one embodiment of the invention. 
     The base station  220  can use a number of different methods to signal to the mobile station  210  to send identical information to the base station  220  in each of a plurality of consecutive communication intervals before processing any received identical information from the mobile station  210 . For example, in one embodiment of invention, when the mobile station  210  and the base station  220  are communicating in accordance with IEEE 802.16e-2005 standard (IEEE 802.16e-2005, “IEEE Standard for Local and Metropolitan Area Networks Part  16 : Air Interface for Fixed and Mobile Broadband Wireless Access Systems”, IEEE Std 802.16e-2005 and IEEE Std 802.16-2004/Cor1-2005), the base station  220  indicates to the mobile station  210  by sending a HARQ UL MAP IE in each of a number of consecutive frames or communication intervals to the mobile station  210 . The HARQ UL MAP IE indicates to the mobile station  210  to send the identical information. 
     In one embodiment of the invention, the base station  220  sets the same ARQ identifier Sequence (AL_SN) field or bit in the HARQ UL MAP IE to indicate to the mobile station  210  to retransmit the same information again. In another embodiment of the invention, the base station  220  sets one or more bits of a register in the mobile station  210  to indicate to the mobile station  210  to transmit the same information in a number of consecutive frames. 
     In another embodiment of the invention, the base station  220  may use a signaling protocol that is not compliant with HARQ protocol to indicate to the mobile station  210  to transmit the same information in a number of consecutive frames. One of ordinary skill in the relevant will readily appreciate that other methods of indicating or signaling can be utilized without affecting the workings of the invention and these other methods can be applied to the invention. 
     The control logic, MAC logic, and the PHY layer logic in the mobile station  210  and the base station  220  can be implemented in any combination of hardware, software and/or firmware. In addition, one or more functionalities of a block may be also performed at least in part by another block. For example, in one embodiment of the invention, the control logic  222  may perform, in place of the MAC logic  224 , one or more functionalities of the MAC logic  224 . 
       FIG. 3  illustrates a protocol structure  300  of a node according to one embodiment of the invention. The protocol structure  300  is compliant at least in part, with the IEEE 802.16m-08/003r8 System Description Draft (SDD) (IEEE 802.16m-08/003r8 SDD, “IEEE 802.16m System Description Document [Draft]”, IEEE 802.16 Broadband Wireless Access Working Group, Apr. 10, 2009). 
     The protocol structure  300  has a network layer  310 , a MAC layer  320 , and a PHY layer  360 . In one embodiment of the invention, the protocol structure  300  is implemented in a base station  220  to improve the link budget of the wireless system  200  using fast HARQ. 
     The MAC layer  320  has two sub layers: MAC common part sub layer  330  and the convergence sub layer  350 . The convergence sub layer  350  classifies a packet according to classification rules, and maps the packet onto a particular transport connection. If the packet is associated with an ARQ connection, the ARQ block  340  logically splits the packet into ARQ blocks. After scheduling, the packet may be fragmented or packed by fragmentation/packing block  341  and a sub-header is added if necessary. The MAC Protocol Data Unit (PDU) formation block  342  may also encrypt the packet and the sub-headers using encryption block  343  and adds a generic MAC header to form a MAC PDU Unit (MPDU). 
     The MAC common part sub layer  330  has a Radio Resource Control and Management (RRCM) block  331  that adjusts radio network parameters based on the traffic load, and also performs load control or balancing, admission control and interference control. The sleep mode management block  332  handles sleep mode operation and generates MAC signaling related to sleep operation. The Quality of Service (QoS) block  333  handles QoS management for each connection. The scheduling and resource multiplexing block  334  schedules and multiplexes packets based on the properties of the connections. The sleep mode management block  332  communicates with the scheduling and resource multiplexing block  334  to operate properly according to the sleep period. 
     The MAC common part sub layer  330  also has a PHY control block  335  that includes a ranging module  336  and a link adaptation module  337 . The PHY control block  335  handles the PHY signaling that includes, but is not limited to, ranging using ranging module  336 , measurement and/or feedback of the communication link using channel quality information (CQI), HARQ acknowledgement (ACK) and negative ACK (NACK), and the like. In one embodiment of the invention, the PHY control module  335  determines whether the quality of a communication link with a station is bad based on an estimation of the quality of the communication link. The estimation of the quality of the communication link or the link condition is based on one or more factors that include, but are not limited to, CQI, HARQ ACK/NACKs, and the like. 
     The link adaptation module  337  performs link adaptation by adjusting the modulation and coding scheme (MCS), and/or the power level. In one embodiment of the invention, the link adaptation module  337  uses one or more factors that include, but are not limited to, the estimation of the quality of the communication link, the QoS required for a particular connection and the like, to select the MCS for the particular connection. For example, the link adaptation module  337  may select a Quadrature Phase Shift Keying (QPSK) modulation, rate ½ and a repetition coding scheme of repetition factor 2 to be used by a mobile station  210  when the link condition is bad. The link adaptation module  337  may also select a higher repetition factor when the link condition deteriorates further. 
     In one embodiment of the invention, the link adaptation module  337  improves the link budget of the wireless system  200  by using fast HARQ protocol. When the link adaptation module  337  detects that a repetition coding scheme is to be used by the mobile station  210 , it sends a request to the control signaling module  338  to send an indication to the mobile station to transmit the same information in a number of consecutive frames, where no repetition coding is used in each transmission. In one embodiment of the invention, the link adaptation module  337  sends a request to the control signaling module  338  to signal to the mobile station  210  in each of a plurality of consecutive frames, the transmission of the same information. In another embodiment of the invention, the link adaptation module  337  performs the functionality of the control signaling module  338  and signals to the mobile station  210  in each of a plurality of consecutive frames, the transmission of the same information. 
     The link adaptation module  337  also detects a repetition factor of the repetition coding scheme in one embodiment of the invention. In one embodiment of the invention, the link adaptation module  337  signals the mobile station  210  in each of a plurality of consecutive frames, where the plurality of consecutive frames is equal to the repetition factor. For example, in one embodiment, if the repetition factor to be set in the repetition coding scheme is four, the link adaptation module  337  sends a request to the control signaling module  338  to signal the mobile station to transmit the same information in four consecutive frames. 
     In another embodiment of the invention, the link adaptation module  337  does not need to detect or determine the repetition factor to be set in the repetition coding scheme. The link adaptation module  337  sets a fixed number of times for the mobile station to transmit the same information. For example, in one embodiment of the invention, when the link adaptation module  337  determines that the quality of the communication link is bad, it will always send a request to the control signaling module  338  to signal the mobile station  210  to transmit the same information in three consecutive frames. In one embodiment of the invention, when the mobile station  210  and the base station  220  are communicating in accordance with IEEE 802.16e-2005 standard, the control signaling module  338  indicates to the mobile station  210  by sending a HARQ UL MAP IE in each of a number of consecutive frames or communication intervals to the mobile station  210 . 
     One of ordinary skill in the relevant will readily appreciate that other methods to select the number of transmissions can be used and these other methods can be applied without affecting the workings of the invention. In another embodiment of invention, the link adaptation module  337  indicates to the mobile station  210  to send the information without using the repetition coding scheme when it determines that the quality of the communication link is bad. By doing so, the base station can achieve higher link budget without the need to increase the amount of channels in order to use a repetition coding scheme. When the quality of the communication link is bad, it is likely that a retransmission of a particular burst is required by the mobile station  210  in order for the base station  220  to decode the particular burst correctly. Instead of waiting to receive the particular burst and processing the particular burst to determine that the particular burst is received incorrectly, the base station  220  uses a fast HARQ to indicate to the mobile station  210  to retransmit the same particular burst before the processing of the particular burst in one embodiment of the invention. 
     Although the link adaptation module  337  is described herein to perform the logic for fast HARQ, it is not meant to be limiting. In another embodiment of the invention, the logic to perform fast HARQ can be performed by other blocks in the protocol structure  300 . In addition, the protocol structure  300  of the node described in  FIG. 3  is not meant to be limiting. One of ordinary skill in the relevant art will readily appreciate that other ways of separating the logical blocks in the protocol structure  300  can be used and these other ways can be applied without affecting the workings of the invention. Similarly, one of ordinary skill in the relevant art will readily appreciate how to apply the logic of HARQ in other wireless communication protocols and these other wireless communication protocols can also be applied without affecting the workings of the invention. 
       FIG. 4  illustrates a timeline  400  of the communication exchanges between a base station  220  and a mobile station  210  in accordance with one embodiment of the invention. For the purposes of illustration, the signaling protocol between the base station and the mobile station are assumed to be operable at least with the HARQ signaling protocol in one embodiment of the invention. 
     The timeline  400  shows six frames  402 ,  404 ,  406 ,  408 ,  410  and  412 . In one embodiment of the invention, the base station  220  determines whether the quality of the communication link with the mobile station  210  is bad. For example, in one embodiment of the invention, the base station  220  detects if a repetition coding scheme is to be used in a transmission of a data burst from the mobile station  210 . The use of the repetition coding scheme indicates to the base station  220  that the quality of the communication link with the mobile station  210  is bad. In another embodiment of the invention, the base station  220  estimates the quality of the communication link. 
     For the purposes of illustration, the base station  220  is assumed to have detected that a repetition coding scheme is to be used by the mobile station and the repetition factor of the repetition coding scheme is set at two. In frame y  402 , the base station  220  sends a HARQ UL MAP IE  420  to the mobile station  210 . The HARQ UL MAP IE  420  indicates to the mobile station  210  to send or transmit a particular information burst to the base station  220 . In one embodiment of the invention, the HARQ UL MAP IE  420  also indicates to the mobile station  210  to send the particular information burst without using the repetition coding scheme. 
     In frame y+1  404 , the base station  220  sends a HARQ UL MAP IE  422  to the mobile station  210 . The HARQ UL MAP IE  422  indicates to the mobile station  210  to send the same or identical particular information burst to the base station  220 . In one embodiment of the invention, the HARQ UL MAP IE  422  also indicates to the mobile station  210  to send the same particular information burst without using the repetition coding scheme. The base station  220  signals the mobile station  210  to send the same information burst in consecutive frames y  402  and y+1  404  without any processing of the received particular information. Unlike the prior art timeline  100 , the base station  220  does not need to wait for the particular information to be received and processed before signaling the mobile station  210  to transmit the same particular information again. This allows the base station  220  to save time when more than one transmission is required before the particular information can be received or decoded successfully. 
     In frame y+1  404 , the mobile station  210  sends a HARQ UL TX burst  424  of the particular information to the base station  220  in response to the received HARQ UL MAP IE  420 . Similarly in frame y+2  406 , the mobile station  210  sends a HARQ UL reTX burst  426  of the particular information to the base station  220  in response to the HARQ UL MAP IE  422 . The mobile station  210  sends the TX bursts in another consecutive number of frames. When the HARQ UL TX burst  424  and the HARQ UL reTX burst  426  are received by the base station  220 , the base station  220  processes the bursts to check for any errors. In one embodiment of the invention, the base station  220  processes the bursts by combining the two bursts together and calculates the cyclic redundancy code (CRC) of the combined bursts to determine if the particular information burst is received correctly. The combination of the two bursts is performed in accordance with, but is not limited to, Chase combining scheme, incremental redundancy scheme and the like. One of ordinary skill in the relevant art will readily appreciate that when incremental redundancy scheme is used in the combination of the two bursts, although each burst has different bits originating from the same information block, it does not affect the workings of the invention. 
     For the purposes of illustration, the particular information burst is assumed to be received correctly and in frame y+4  410 , the base station  220  is assumed to have determined that the quality of the communication link between the mobile station  210  and the base station  220  is good. In frame y+4  410 , the base station sends a HARQ UL MAP IE  428  to the mobile station  210  to send another particular information burst to the base station  220 . In frame y+5  412 , the mobile station  210  sends a HARQ UL TX burst of the other particular information burst  430  after receiving the HARQ UL MAP IE  428  from the base station  220 . The base station  220  does not send a retransmission request in frame y+4  410  as the base station  220 , after combining the HARQ UL TX burst  424  and the HARQ UL reTX burst  426 , determines that the calculated CRC of the combined bursts is not corrupted. In one embodiment of the invention, the mobile station  210  uses the same HARQ channel to transmit the HARQ UL TX burst of the other particular information burst  430 . 
     In another embodiment of the invention, the fast HARQ scheme applies to retransmission bursts as well. For example, in one embodiment of the invention, if the base station  220  determines that the CRC of the HARQ UL reTX burst  426  is corrupted, it can requests retransmission in consecutive frames y+5  412  and y+6 (not shown in  FIG. 4 ) of the HARQ UL reTX burst  426 . One of ordinary skill in the relevant art can use the fast HARQ scheme in other scenarios of the HARQ protocol and it does not affect the workings of the invention. 
     Although the base station  220  is illustrated as the node to use fast HARQ to improve the link budget of the wireless system  200 , it is not meant to be limiting. The mobile station  210  can also use fast HARQ to improve the link budget of the wireless system  200  in another embodiment of the invention. One of ordinary skill in the relevant art will readily appreciate how to apply the logic and methods described for fast HARQ in the mobile station  210 . 
     In a scenario when the mobile station  210  is far away from the base station  220  or when the condition of the link condition between the mobile station  210  and the base station  220  is bad, the use of fast HARQ by the base station  220  improves the uplink link budget of the mobile station  210 . The mobile station  210  has to transmit information to the base station  220  at high power per tone in order to achieve lower error rate. However, if the mobile station  220  has limited uplink or transmit power, the number of sub channels and slots that it can use is limited. To improve the uplink budget of the mobile station  210 , the base station  220  indicates to the mobile station  210  to send identical information in each of a plurality of consecutive communication intervals without any processing of the identical information. The indication is sent by the base station  220  before the first transmission of the identical information is received by the base station  220 . In this way, the mobile station  210  effectively increases the received power per tone in the base station  220 . 
       FIG. 5  illustrates a flow chart  500  of the steps to improve the link budget of a wireless system  200  in accordance with one embodiment of the invention. For the purpose of illustration, the steps in flow chart  500  are discussed with reference to a receiving node that is communicating with a transmitting node. 
     In step  510 , the receiving node checks if the link condition between the transmitting node and the receiving node is bad. In another embodiment of the invention, the receiving node detects if a repetition coding scheme is to be used by the transmitting node to transmit information bursts. If no, the receiving node uses normal or conventional HARQ protocol to communicate with the transmitting node and the flow ends. If yes, the receiving node signals or indicates to the transmitting node to transmit the same particular information burst in X consecutive frames to the receiving node in step  520 . In one embodiment of the invention, the number X is the repetition factor of the repetition coding scheme that is to be used by the transmitting node. In another embodiment of the invention, the number X is a pre-determined number. In yet another embodiment of the invention, the number X is a variable number that is dependant on factors including, but not limited to, CQI, number of HARQ retransmissions, maximum latency requirements, and the like. The number X can be different for each new transmission or retransmission. 
     In step  530 , the receiving node waits for a burst of the particular information from the transmitting node. In step  540 , the receiving node checks if a burst of the particular information is received. If no, the flow goes back to step  530  and continues to wait for a burst of the particular information from the transmitting node. If yes, the receiving node processes the burst of the particular information in step  550 . In one embodiment of the invention, the receiving node processes or parses the burst by combining two or more received bursts of the particular information and calculates the CRC of the combined burst. 
     The receiving node checks the CRC of the burst or combined bursts to check if there is any error in step  560 . If there are no errors, the receiving node stops the signaling to the transmitting node if the receiving node has not completed signaling the transmitting node in X consecutive frames in optional step  565 . The receiving node also discards burst(s) from the transmitting node if the particular information has been received and/or decoded successfully in optional step  565  and the flow ends. 
     If there are errors, the receiving node checks if there are pending bursts from the transmitting node that has not been received in step  570 . For example, in one embodiment of the invention, the receiving node checks if X bursts have been received to determine if there are pending bursts from the transmitting node that have not been received in step  570 . If yes, the flow  500  goes back to step  530  and continues to wait for a burst of the particular information from the transmitting node. If no, the flow  500  goes back to step  520  and signals or indicates to the transmitting node to transmit the same particular information burst in X consecutive frames to the receiving node. 
     Although the flow  500  has been discussed with reference to frames, it is not meant to be limiting. Other methods of dividing the communication intervals can also be applied without affecting the workings of the invention. In addition, the sequence of the steps in the flow  500  is not meant to be limiting and the sequence may also be interchanged without affecting the workings of the invention. 
       FIG. 6  illustrates a system  600  to implement the methods disclosed herein in accordance with one embodiment of the invention. The system  600  includes but is not limited to, a desktop computer, a laptop computer, a notebook computer, a netbook computer, a personal digital assistant (PDA), a server, a workstation, a cellular telephone, a mobile computing device, an Internet appliance or any other type of computing device. In another embodiment, the system  600  used to implement the methods disclosed herein may be a system on a chip (SOC) system. 
     The system  600  includes a memory/graphics controller  620  and an I/O controller  650 . The memory/graphics controller  620  typically provides memory and I/O management functions, as well as a plurality of general purpose and/or special purpose registers, timers, etc. that are accessible or used by the processor  610 . The processor  610  may be implemented using one or more processors or implemented using multi-core processors. In another embodiment of the invention, the memory/graphics controller  620  is integrated with the processor  610 . 
     The memory/graphics controller  620  performs functions that enable the processor  610  to access and communicate with a main memory  640  that includes a volatile memory  642  and/or a non-volatile memory  644 . The volatile memory  642  includes, but is not limited to, Synchronous Dynamic Random Access Memory (SDRAM), Dynamic Random Access Memory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM), and/or any other type of random access memory device. The non-volatile memory  644  includes, but is not limited to, NAND flash memory, ROM, EEPROM, and/or any other desired type of memory device. The main memory  640  stores information and instructions to be executed by the processor(s)  610 . The main memory  640  may also store temporary variables or other intermediate information while the processor  610  is executing instructions. 
     The memory/graphics controller  620  is connected to a display device  630  that includes, but not limited to, liquid crystal displays (LCDs), cathode ray tube (CRT) displays, or any other form of visual display device. The I/O controller  650  is coupled with, but is not limited to, a storage medium (media)  660 , a network interface  670 , and a keyboard/mouse  680 . In particular, the I/O controller  650  performs functions that enable the processor  610  to communicate with the storage medium  660 , the network interface  670 , and the keyboard/mouse  680 . 
     The network interface  670  is implemented using any type of well known network interface standard including, but is not limited to, an Ethernet interface, a universal serial bus (USB), a Peripheral Component Interconnect (PCI) Express interface, a wireless interface and/or any other suitable type of interface. The wireless interface allows the system  600  to function as a wireless node or station. 
     Although examples of the embodiments of the disclosed subject matter are described, one of ordinary skill in the relevant art will readily appreciate that many other methods of implementing the disclosed subject matter may alternatively be used. In the preceding description, various aspects of the disclosed subject matter have been described. For purposes of explanation, specific numbers, systems, and configurations were set forth in order to provide a thorough understanding of the subject matter. However, it is apparent to one skilled in the relevant art having the benefit of this disclosure that the subject matter may be practiced without the specific details. In other instances, well-known features, components, or modules were omitted, simplified, combined, or split in order not to obscure the disclosed subject matter. 
     The term “is operable” used herein means that the device, system, protocol etc, is able to operate or is adapted to operate for its desired functionality when the device or system is in off-powered state. Various embodiments of the disclosed subject matter may be implemented in hardware, firmware, software, or combination thereof, and may be described by reference to or in conjunction with program code, such as instructions, functions, procedures, data structures, logic, application programs, design representations or formats for simulation, emulation, and fabrication of a design, which when accessed by a machine results in the machine performing tasks, defining abstract data types or low-level hardware contexts, or producing a result. 
     The techniques shown in the figures can be implemented using code and data stored and executed on one or more computing devices such as general purpose computers or computing devices. Such computing devices store and communicate (internally and with other computing devices over a network) code and data using machine-readable media, such as machine readable storage media (e.g., magnetic disks; optical disks; random access memory; read only memory; flash memory devices; phase-change memory) and machine readable communication media (e.g., electrical, optical, acoustical or other form of propagated signals—such as carrier waves, infrared signals, digital signals, etc.). 
     While the disclosed subject matter has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments, as well as other embodiments of the subject matter, which are apparent to persons skilled in the art to which the disclosed subject matter pertains are deemed to lie within the scope of the disclosed subject matter.

Metadata:
Filing Date: 20200316
Publication Date: 20211005
Grant Date: 20211005
Priority Date: 20090714
Inventors: BERGMAN, ARAN
Assignee: APPLE INC
CPC Classifications: [{"code": "H04B17/309", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1896", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1816", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/0015", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0015", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/1825", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1825", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1825", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04B17/309", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0015", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1816", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/1896", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1816", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/0015", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1825", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0061", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1819", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1896", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/1825", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/0015", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 43450107