TWI387251B - Method and apparatus for link control in wireless communications - Google Patents

Description

Method and apparatus for controlling links in wireless communication [35 U.S.C. § 119 priority request]

This application claims priority over the provisional application No. 60 of the application for "Method and Apparatus for Link Control in Wireless Communications", which was filed on June 16, 2004, and entitled "Method and Apparatus for Link Control in Wireless Communications". Provisional Application No. 60, No. 580, 458, and May 4, 2005, entitled "Method and Apparatus for Link Control in Wireless Communications" / 677, 975, both of which are incorporated herein by reference.

The present invention relates generally to wireless communications, and more particularly to link control in wireless communications.

The increased demand for radio resources carrying voice and data messages can sometimes result in increased transmission errors due to competition between simultaneously transmitted signals. Transmission errors can also be caused by bad weather, signal strength obscuration, electrical interference, or other conditions that affect the air interface, resulting in the loss or destruction of one or more packets in a wireless communication. When a lost or corrupted packet occurs, additional wireless system resources are typically required to retransmit the lost data.

1A and 1B depict a conventional scheme for recovering lost or corrupted wireless packets in W-CDMA. The diagrams illustrate the receiver receiving the poll 120 from the sender, the lost packets 101-105, the status report including the NAKs (negative acknowledgement) 131-133, the status prohibit timers 141-143, and the retransmission packet 111- A typical timing relationship between 115. Figure 1A shows various signals 101-120 received at a receiver, while Figure 1B shows NAKs 131-133 and retransmissions 111-115 transmitted between the receiver and the sender. Time slots 101-105 represent packets that are corrupted at the receiver.

Upon determining that the packet 101 has been corrupted, the receiver immediately transmits a status report back to the sender, the status report including a NAK 131 instructing the sender to initiate retransmission of one of the corrupted packets 101. Conventional W-CDMA status reports typically have a requirement to include NAKs for all pending sequence number intervals that exist since the last sequence number received sequentially. This inclusion of all pending sequence numbers in the abuse status report wastes valuable wireless resources. For example, when a status report with NAKs for a corrupted packet (which has been in retransmission) is sent back to the sender, resulting in a second, non-essential false retransmission of the sender, wasted Wireless resources.

To avoid triggering false retransmissions and wasting valuable wireless bandwidth, W-CDMA has introduced a state inhibit mechanism, state disable timers 141-143. Once any status report is issued, a general status prohibit timer is started. Currently, W-CDMA requires that after the state inhibit timer is started, no further status report is transmitted until the timer expires. Any interrogation received from the sender while a state inhibit timer is running will be delayed until the timer expires. Once a corrupted packet is detected, the status report with the NAK for the corrupted packet will be delayed until the pending state disable timer expires.

In FIG. 1, once the receiver transmits a status report including NAK 131, the status prohibit timer 141 is initiated, which prevents transmission of any further status reports until the timer expires. Therefore, when the corrupted packet 102 is detected (during the state inhibit timer 141 is still running), the status report with the NAK 132 for the corrupted packet 102 will be delayed until the state inhibit timer 141 expires. When the state inhibit timer 141 has expired, as shown in FIGS. 1A and 1B, the retransmission of the corrupted packet 101 has been received by the receiver in the form of a retransmission packet 111. Once the state inhibit timer 141 has expired, the receiver may send another status report including the NAK 132 requesting retransmission of the corrupted packet 102 previously detected during the state disable timer 141 still running.

The present invention is directed to overcoming or at least reducing the effects of one or more of the problems described above.

The aspects of the invention disclosed herein address the above needs by providing a status reporting mechanism for the RLC-AM mode that allows for configuration flexibility and the ability to receive unordered PDUs.

In accordance with various aspects of the present invention, an apparatus, method and computer readable medium for controlling a communication link are provided. The aspect includes detecting a corrupted packet from a transmitting entity at a receiving entity and transmitting a negative acknowledgement (NAK) from the receiving entity back to the transmitting entity. A NAK disable timer associated with the corrupted packet is initiated because of the NAK that should be sent.

In accordance with an aspect of the invention, the NAK disable timer is associated with a particular corrupted packet and prevents any additional NAKs from being sent for a particular corrupted packet until the NAK disable timer expires. However, if other corrupted packets are detected, the NAK disable timer cannot prevent other NAKs from being sent for other corrupted packets. According to one aspect of the invention, the NAK inhibit timer is initially set to run a round trip time (RTT) or more.

According to one aspect of the invention, an ACK inhibit timer is initiated. The ACK inhibit timer may have a duration of time depending on the desired responsiveness of moving the RLC window forward, the duration being longer or shorter than the duration of the NAK disable timer. The ACK inhibit timer only delays the transmission of the ACK status report until the ACK inhibit timer expires. However, the ACK inhibit timer does not delay the transmission of status reports containing NAKs.

According to one aspect of the invention, an ACK counter is initiated after an ACK is sent from the receiving entity to the transmitting entity. The ACK counter increments each received PDU to maintain tracking of the receiver window fill level. If the ACK counter reaches a predetermined threshold, another ACK is sent. The predetermined threshold can be specified as a percentage of the width of an RLC window.

The various aspects of the invention disclosed in the following description and related drawings are intended to illustrate various embodiments of the invention. Various alternative embodiments are contemplated without departing from the spirit and scope of the invention. Some of the elements that are well known to those skilled in the art may not be described or may be omitted in order to avoid obscuring the details of the present invention.

The terms "transport entity" (or "sender") and "receiving entity" (or "receiver") as used throughout this disclosure and the scope of the claims are used to refer to a particular packet (eg, a The relationship between the destruction of the package). The transmission system transmits the packet's communication station or device. The receiving real system receives the packet or a station or device that intends to receive the packet in the event of a corrupted packet. A device participating in two-way communication is a transmission entity of a certain packet and a receiving entity of another packet. The transmitting entity has both a receiving circuit and a transmitting circuit, as is the receiving entity. The transmitting entity and the receiving entity may be wireless stations (e.g., mobile stations) or may be fixed stations that communicate by cable or wire. As used herein, the term "agreeable data unit (PDU)" is a unit of information, packet or frame that is exchanged between a peer network through a network or in a network. As used herein, the terms "PDU" and "packet" are used interchangeably and are defined to have the same meaning.

2 depicts a typical wireless network architecture 200 that supports communication between a fixed station and a wireless station in accordance with various embodiments of the present invention. Several competing systems have recently become popular for wireless transmission of sound, data and content. One of these systems is W-CDMA (Broadband Code Multiple Multiple Access), which was first published in December 1999 by 3GPP (3rd Generation Partnership for Mobile Communications). The initial 1999 W-CDMA publication is sometimes referred to as R-99. Although various examples and explanations provided herein refer to a W-CDMA system, various embodiments may be implemented in accordance with a variety of other wireless or wired communication standards, including W-CDMA, cdma2000, GSM/GPRS, or various other technologies. Various publications or implementations.

The wireless system 200 includes a core network 250, one or more radio network subsystems 240, a wireless user device 210, and a wired user device (e.g., landline telephone 260). The radio network subsystems (RNS 240) also each include one or more radio network controllers (RNCs 230) each communicatively coupled to a plurality of base stations (in W-CDMA, which are commonly referred to as "Node-B"). Node-B may take various forms, be referred to by other names, or have other modes of sharing systems, depending on the particular details of this embodiment. For example, in some systems, a Node B 220 base station may be referred to as a Base Transceiver Station (BTS) or a Base Station System (BSS). In some embodiments, the radio network controller labeled RNC 230 in the figure may take other forms, be referred to by other names, or have other shared systems, such as a base station controller (BSC), Mobile Switching Center (MSC) or a Serving GPRS Support Node (SGSN). An SGSN is typically the core network entity that handles the packet switched connection, while an MSC is the core network entity that handles the circuit switched connection. 2 depicts a wireless user equipment UE 210, which may be referred to by a plurality of different names, such as a cellular telephone, a mobile station, a wireless handset, or the like. The scope of the present invention encompasses these and other systems, names, terms, and implementations of elements for similar types of wireless systems.

The network depicted in this figure is merely exemplary and may include any system that allows communication over the air or by fixed cable or wire communication paths between components. The system can be connected by the method depicted in Figure 2 or other methods known to those skilled in the art. The UE 210 and the fixed station 260 can be implemented in the form of a plurality of different types of wired or wireless devices including one or more phones, cellular phones, wirelessly connected computers, PDAs (personal digital assistants), pagers, navigation devices , music or video content download unit, wireless gaming device, inventory control unit or other similar type of device that communicates wirelessly via an empty mediation plane. The cellular or other wireless communication service can communicate with a carrier network via a data link or other network link over the fixed network 250. The fixed network 250 can be a public switched telephone network (PSTN), the Internet. Road, Integrated Services Digital Network (ISDN), one or more local area networks (LANs), wide area networks (WANs), virtual private networks (VPNs), or other such networks. Communication can also be carried out using a fixed station 260 that communicates over the PSTN or another fixed network 250.

The wireless system 200 controls messages or other information that is typically sent by the RNS 240 to the UE 210 as a data packet. Each RNC 230 can be connected to one or more Node-B 220 base stations. If more than one Node-B 220 is associated with a particular UE 210, then all Node-Bs 220 in the active set of UEs 210 may have the same concept of E-DCH frame number in order to be able to correctly interpret and classify the traffic to and from Packets of two different nodes-B 220 participating in Soft Handoff (SHO) with UE 210. The subsystem RNS 240, including the RNC 230, controls the radio link between the Node-Bs 220 and the UE 210. In general, RNC 230 includes logic (e.g., a processor or computer) to manage or control wireless UE 210. The logic of RNC 230 manages and controls several functions, such as call routing, registration, authentication, location update, handover, and/or coding for wireless UE 210 registered at Node-B associated with the RNC 230. Program, etc.

The RNC 230 is coupled to the Node-Bs 220 in a manner similar to the interconnection of the network 250 by a network configured for data transfer and/or voice information (typically via a fixed communication line). Communication between the various RNC 230 and Node-B 220 elements is typically carried out by a landline network that may include portions of the Internet and PSTN. Upstream, the RNC 230 can be connected to multiple networks, such as the networks mentioned above (eg, PSTN, Internet, ISDN, or the like), allowing the wireless UE 210 device to access a wider range. Communication network. In addition to voice transmission, data can be transmitted using Short Message Service (SMS) or other wireless transmission (OTA) methods known in the art.

Each Node-B 220 has one or more transmitters and receivers to transmit and receive information to and from one or more UEs 210 associated with or registered with the Node-B 220. The Node-B 220 broadcasts data messages or other information to the UE 210 wirelessly by an OTA method known to those skilled in the art. For example, the wireless signal between the UE 210 and the Node-B 220 may be based on any of a number of different technologies including, but not limited to, CDMA (Coded Multiple Access), TDMA (Time Division Multiple Close), FDMA (minutes) Frequency multiple proximity), OFDM (Orthogonal Frequency Division Multiplexing) and any other system that uses a mixture of coding techniques such as GSM, or other similar wireless protocols used in communication or data networks.

FIG. 3 depicts details of UE 210 and Node-B 220. Node-B 220 includes an encoder/decoder 225 that encodes the information to be transmitted and decodes the received information in a suitable encoding protocol or scheme. Node-B 220 includes receiver/transmitter circuitry 227 for wireless The method receives and transmits packets from the UE 210 and is used to transmit and receive packets by the RNC 230 (the packets can be transmitted via a landline). Node-B 220 also includes a processor 221 that includes circuitry or other logic capable of executing or controlling the processes and activities involved in wireless communications, and in particular the processes and activities described herein.

Node-B 220 may also be configured to include a memory 223 for storing various protocols, routines, procedures, and software intended for use in performing the wireless communications described herein. For example, memory 223 can store one or more transmissions, protocols, protocols, or strategies for communicating with a UE 210. Such transmissions, schemes, strategies and agreements include information on the timing of retransmissions due to loss or destruction of packets, redundancy version coding (if any) and any coding scheme or agreement intended for wireless communication transmission and reception. This information may also be stored in the memory of the RNC 230 and transmitted to the Node-B 220 as needed or during periodic updates and system maintenance.

As shown in FIG. 3, an embodiment of UE 210 typically includes a processor or other logic 207, memory 209, and encoder/decoder circuitry 211 that performs functions similar to those of corresponding portions of Node-B 220. . For example, encoder circuit 211 or other similar circuitry at UE 210 may be configured to encode or otherwise encapsulate the data in a packet for transmission to Node-B 220. Each UE 210 also has an antenna 213, a receiver/transmitter circuit 215, and other electronic devices known to those skilled in the art for wirelessly receiving and transmitting information. Receiver circuit 215 is configured to detect if the received packet is corrupted, and the transmission path is configured to send a NAK back to the transmitting entity (e.g., Node-B 220) for a corrupted packet. As a transport entity, both Node-B 220 and UE 210 should have sufficient memory to store enough packets to prevent the window from stalling before the window is moved before receiving an ACK.

The UE 210 includes logic for controlling the functionality of the UE 210, which is labeled as processor 207 in FIG. In practice, the logic can be configured in the form of one or more processing circuits that execute the configured logic, a microprocessor, a digital signal processor (DSP), a microcontroller, or the like or A combination of other similar hardware, software, and/or firmware configured to perform at least the operations described herein (for example, UE 210 activity described herein).

Depending on the transmission conditions of the channel, bit errors can cause damage that can be resolved by error recovery or retransmission techniques. The probability that a frame contains a meta-error is often a function of the bit error rate of the channel and the amount of data in the example or the length of the frame. The wireless system 200 can be constructed with one or more mechanisms for detecting and/or recovering from transmissions that suffer bit errors, such as automatic repeat request (ARQ) and/or forward error correction (FEC) or hybrids. ARQ (HARQ). In addition to the ARQ acknowledgement feedback technology, the HARQ system adds the use of Forward Error Correction (FEC).

Wireless systems typically use a feedback channel that allows the receiver to send information about the success or failure of the transmission back to the transmitter. Although some error recovery schemes can be implemented using in-band feedback, an out-of-band feedback channel is often used to implement an error recovery scheme. ARQ can be explicitly implemented using a denial (NAK, sometimes denoted NACK) to request a retransmission. Alternatively, the ARQ can be implicitly implemented using an acknowledgment (ACK) in conjunction with a timeout rule.

Upon receiving a transmission from the UE 210, the Node-B 220 can be configured to transmit an ARQ signal to provide feedback regarding the transmission in the form of an ACK or a NAK. For example, in a system with explicit out-of-band ARQ feedback, if the data from the UE 210 is corrupted or lost before being received by the Node-B 220, the Node-B sends back a NAK indicating the UE 210. The failed transmission should be retransmitted.

The wireless system 200 can be constructed in the form of an R-99 W-CDMA system or according to several other wireless standards or technologies. For example, the wireless system may conform to the Universal Mobile Telecommunications System (UMTS) Radio Link Control (RLC) Protocol Specification (3GPP TS 25.322 version 6.0.0 Publication 6), which is expressly incorporated herein by reference in its entirety. In R-99 W-CDMA, the Radio Link Control (RLC) protocol handles frame formation and retransmission functionality. The RLC protocol supports three separate transmission modes: Transparent (RLC-TM), Unconfirmed (RLC-UM), and Confirmed (RLC-AM). The RLC in combination with the physical layer is sufficient to flexibly allow support for different types of QoS (eg, different maximum delays and residual error rates). With the exception of minor improvements, the conventional RLC implementation has not been modified as it was created as part of R-99. Most of the original RLC components were generated in the early stages of UMTS development and have remained unchanged since then. With the introduction of new physical layer features, it was decided to circumvent the modification of the RLC and instead try to resolve some of its limitations in other layers. Doing so, for example, may accommodate the need for out-of-order reception of Protocol Data Units (PDUs) for High Speed Downlink Packet Access (HSDPA).

R-99 W-CDMA uses a state prohibition mechanism to ensure that there are no false retransmissions. The R-99 also uses several interrogation schemes to ensure that at least one interrogation is received while the state prohibits the organization from running. The R-99 state disable value is typically set to be 40 or 60 ms longer than the desired round trip time to account for the limited bandwidth available in performing the retransmissions. There are multiple mechanisms that can be used to trigger status reporting. For example, the status report can be sent periodically at regular intervals, or if an interruption in the sequence of sequence numbers is detected, a status report can be triggered by a lost PDU. Alternatively, the status report may be initiated in response to a query received by the transmitting entity requesting a status report from the other end of the communication link. The transmitting entity can indicate an interrogation, for example, by setting a bit on the RLC-AM header.

For using a poll to trigger a status report, there are multiple mechanisms that can be used to initiate the transmission of the interrogation by the transport entity. The mechanisms for initiating interrogation include: periodic interrogation, interrogation of the last PDU in the transmission buffer, use of a polling timer, window-based interrogation, for each Poll_PDU PDUs (agreement data unit) or each Poll_SDU Counter-based inquiry of SDUs (Service Data Unit). These polling triggers operate as follows. For periodic interrogation, an interrogation is triggered at predetermined periodic intervals. For transmission buffer detection, upon detecting the transmission buffer or the last PDU in the retransmission buffer, an inquiry is initiated, for example, the inquiry can be set in the last PDU of the transmission or retransmission buffer. On the header. These transmit or retransmit buffer headers can be independently configured to achieve this interrogation. To use a polling timer, if the transmitted data is not positively acknowledged after the expiration of the timer, the poll is triggered by a predetermined, fixed amount of time after the previous interrogation. This interrogation timer scheme ensures redundancy in the event of a missed inquiry. For window-based interrogation, an interrogation can be triggered after the transmission window has moved forward beyond a portion of the transmission window.

For the inquiry of each Poll_PDU PDUs initiated by the counter, after the Poll_PDU PDUs message transmission, an inquiry is triggered when the state variable VT (PDU) reaches the Poll_PDU value set by the upper layer. The state variable VT (PDU) is incremented by one each time an AMD (Accepted Mode Data) PDU (including PDU retransmission) is transmitted. Similarly, for the inquiry of each Poll_SDU SDUs, when the state variable VT (SDU) reaches the Poll_PDU value set by the upper layer, an inquiry is triggered after the transmission of the Poll_SDU SDUs. The state variable (SDU) is incremented by one for a given SDU when the AMD PDU carrying the first SDU segment is scheduled for the first transmission.

The RLC-AM receiving entity maintains a plurality of state variables including VR(R), VR(H), and VR(MR). The state variable VR(R) represents the last sequence number received in sequence. VR(R) marks the beginning of the receiver window. The state variable VR(H) is the highest sequence number of any received PDU. The state variable VR(MR) will be accepted as the highest valid sequence number. VR (MR) marks the end of the receiver window. Therefore, VR(MR) is set to the VR(R)+Rx window size. With regard to the terms RLC window, receiver window, and transmission window, it should be noted that in the art, such terms are sometimes used interchangeably to have different meanings. When configuring an RLC, two windows of the same size can be created: the receiver window at the receiving entity (sometimes called the receiving window) and the transmission window at the transport entity. When receiving sequential PDUs, the receiving window is advanced. If the PDUs are not received in sequence (eg, there are holes in one or more corrupted PDUs), the receiving window waits until the one of the lost PDUs is received for retransmission or the lost PDU is discarded (eg, if The maximum amount of retransmission). Whenever the transmitting entity receives an ACK from the receiving entity, indicating that PDUs up to a certain number of PDUs have been properly received in sequence, the transmission window is forwarded. The term RLC is often used to refer to RLC.

As noted above, each RLC status report in the legacy system needs to include NAKs for all holes or data gaps detected in the receiver window. Therefore, the conventional network uses a state that is slightly longer than the RLC round trip time. For example, in a conventional R-99 W-CDMA implementation, the state inhibit value is typically set to be 40 to 60 ms longer than the desired round trip time. In the conventional W-CDMA configuration, a status report is transmitted once per RLC round trip time during ongoing data transmission.

The inventors have recognized the drawback of delay due to the transmission of only one status report per round trip time (RTT). The requirement that W-CDMA does not transmit further status reports while a legacy state inhibit timer is running will often result in a delay in retransmission of corrupted packets. Figure 4 illustrates the delay in retransmitting a packet from a lost or corrupted PDUs for a conventional scenario in which only one status report is transmitted per RTT. In this example, the identifiers 401, 403, 405, 407, and 409 represent status reports sent back from the receiving entity to the transmitting entity. Once the status report 401 is transmitted, a status prohibit timer 421 is activated. According to the conventional W-CDMA implementation, the status report may not be sent until the status prohibit timer 421 expires. After the state inhibit timer 421 expires, the status report 403 can be transmitted after a delay 431 caused by the state inhibit timer 421. This same situation occurs for all status reports sent in the conventional W-CDMA. After each status report 401-409, one of the start state disable timers 421-427 is enabled and remains active for one RTT or slightly more than one RTT. The disable timers 421-427 prevent the transmission of the next status report until the pending status prohibit timers 421-427 expire. Status reports 401-409 include NAKs for all of the holes detected in the respective receiver window (e.g., for corrupted PDUs 411, 413, and 415).

In this example, blocks 411, 413, and 415 indicate that three new holes are detected in the RLC sequence numbers. Since one of the state inhibit timers 421-427 is active when each hole is detected, there is a delay between the detection of a hole and the transmission of the corresponding NAK in the next status report. The delays of the holes 411, 413, and 415 are shown as 431, 433, and 435, respectively. Since the transmission errors are not related to the status reporting timing, the additional delay can be evenly distributed between zero (0) and the value of the status prohibit timer. In the conventional system, the length of the state prohibition timer is set to be close to the RTT. This means that the total delay between the time a hole is detected and the time the retransmission is received is equal to an average of 1.5 times the round trip time. It should be noted that this delay only affects the first retransmission of a particular hole. If the first retransmission of the hole fails, the second retransmission of the hole and each subsequent retransmission will only delay one RTT.

For protocols that rely on the transmitter window to perform flow control, acknowledgment transmission, etc. (eg, RLC-AM and TCP), ACKs are used to push the transmission window forward. For a fairly large window size, the delay in sending a confirmation does not significantly affect performance. In addition, in the conventional RLC-AM implementation, ACKs are transmitted at the same frequency regardless of whether there are any NAKs to be reported. The transmitting entity shall be able to store several PDUs to ensure that, assuming there is no error during the transmission, the window is not stalled until an ACK is received to advance the window. Typically, the amount of data that the transport entity needs to buffer between receiving two consecutive status reports (eg, maximum buffer data) is equivalent to the amount of data that can be transmitted in twice the round trip time. This PDU buffer is more important in HSDPA than in R-99 because the RLC window size is often more limited in HSDPA. For example, assuming a 200 ms round trip time and a 320 bit PDU size, the maximum achievable data rate would be: 2048x320 / (2x0.2) = 1.63 Mbps. In the case of HSDPA, this state prohibition can usually be configured to a small value because, under good channel conditions, the residual error rate is extremely low. However, if we use the same configuration across the unit, a large number of false retransmissions will affect users in areas with poor channel conditions.

One of the drawbacks of conventional RLC is that reporting status transmissions more frequently than once per RTT can result in spurious retransmissions. However, if the status report is limited to no more than one per RTT, then a longer delay will also result in advancing the RLC window and sending NAKs for lost PDUs. Conventional RLC implementations include several limitations that make it impossible to adjust for such NAK and ACK delays. For example, the usage status report includes NAKs for all holes in the sequence number (SN), and the status report is sent at the same rate regardless of whether any NAKs are present and although the fact that ACKs may not be sent so frequently may be required. This requirement of the conventional RLC implementation results in a false retransmission unless the reporting status period is greater than the round trip time.

The various embodiments disclosed herein are more flexible by independently tracking holes in the PDU sequence. In addition to the normal state disable timer (which applies to all holes), a separate timer can be provided for each hole. This timer, called the NAK disable timer, does not prevent the transmission of a status PDU. The NAK disable timer for a given hole prevents NAKs that would involve the hole from being included in any transmitted status report until the NAK disable timer for that given hole expires. The combination of interrogation and status prohibition allows the system to define the rate at which the report is generated, and also enables the loss of the PDU status report trigger to be used effectively.

The conventional schemes depicted in FIGS. 1A and 1B may sometimes require fewer NAK transmissions than the various embodiments disclosed herein (eg, FIGS. 5A-5B, 531, 532, 533, and 534) (eg, 131, 132 and 133).

However, this conventional solution does not allow for a reduction in the delay in the transmit feedback. These embodiments allow for greater flexibility in increasing the number of status reports in the feedback delay. In accordance with such embodiments disclosed herein, transmitting more frequent status report transmissions tends to provide a more uniform retransmission allocation. Further, the state inhibit timers of the various embodiments disclosed herein can be set to a shorter value than the state inhibit timer of the conventional system without increasing the probability of false retransmissions.

An ACK is often sent from the receiving entity back to the transmitting entity to report back to the last sequence code received in sequence, i.e., to update the beginning of the RLC window. An ACK will typically be included in a status report containing one of the NAKs. However, if there are no available NAKs, depending on the size of the supported window, triggering an ACK transmission may be meaningless to avoid unnecessarily triggering an ACK when there is no intention to send a NAK. Various embodiments disclosed herein An "ACK inhibit timer" is provided. This timer can be set to a value longer than the NAK disable timer. If a state inhibit timer is running or if its associated NAK disable timer has not expired, then only the status report including the NAKs is delayed. However, if the state inhibit timer or the ACK inhibit timer is running, the ACK status report will be delayed, that is, the status report with only one ACK instead of NAKs. Since the NAK disable timer is NAK-specific in various embodiments, it will not affect the transmission of a status report with a different NAK or any ACK.

5A-B depict several aspects of a scheme for recovering lost or corrupted wireless packets in accordance with various embodiments disclosed herein. Figure 5A illustrates a NAK inhibit timer that shows a polling 520 received by the receiving entity from the transmitting entity, lost packets 501-505, status reports that send NAKs 531-534 back to the transmitting entity, NAK inhibit timing An example timing relationship between the 541-544 and retransmission packets 511-515. Time slots 501-505 represent packets that are corrupted at the receiving entity. While FIG. 5A shows various signals 501-520 received by the receiving entity, FIG. 5B shows NAKs 531-534 and retransmissions 511-515 transmitted between the receiving entity and the transmitting entity. For the sake of clarity, the ACK inhibit timer and the state disable timer are not considered in explaining the NAK disable timer provided in connection with FIGS. 5A and 5B. The ACK inhibit timer and the status prohibit timer will be discussed below in conjunction with FIGS. 6A and 6B.

Upon determining that a packet (e.g., packet 501) has been corrupted, the receiving entity immediately transmits a status report back to the transmitting entity, the status report including a NAK 531 instructing the transmitting entity to initiate retransmission of one of the corrupted packets 501. To avoid triggering a false retransmission, a NAK disable timer 541 is initiated. According to various embodiments, upon transmitting a status report containing a NAK, a NAK disable timer is initiated. Unlike the state disable timers of conventional W-CDMA implementations, the NAK disable timers disclosed herein are NAK-specific. Because of the NAK-specific, a NAK disable timer only blocks further NAKs for a particular lost PDU, or if there are holes in one of several consecutive lost PDUs, the NAK disable timer blocks the consecutive lost PDUs for the hole. Further NAKs until the NAK disable timer expires. As used herein, a NAK-specific NAK disable timer is said to be associated with one or more corrupted packets, and therefore no additional NAKs will be sent for one or more of the corrupted packets until NAK disables timing. The device expires. This is different from the general state disable timer of the conventional technique, which does not completely block any further status reports until the timer expires.

As shown in FIG. 5, upon transmitting the status report including the NAK 531 from the receiving entity, the status prohibit timer 541 is immediately activated, thereby preventing transmission of further NAKs for the corrupted packet 501 until the NAK disable timer 541 full. However, since the NAK disable timer 541 is NAK-specific with respect to the corrupted packet 501, other NAKs for other corrupted PDUs cannot be blocked. Thus, once the corrupted PDU 502 is detected, the receiving entity is still able to send the NAK 532 despite the fact that the NAK disable timer 541 is still running. It is not necessary to omit the interrogation received from the transmitting entity during the operation of a NAK inhibit timer due to the NAK disable timer. As described above, if there is one of two or more consecutive missing PDUs, the NAK inhibit timer will block further NAKs for the consecutive lost PDUs for the hole until the NAK disable timer expires. For example, corrupted PDUs 504 and 505 form one of two consecutive missing PDUs. In some embodiments, overhead is saved by sending a single NAK 534 for two corrupted packets 504 and 505 instead of sending two NAKs. In these examples, a single NAK disable timer 544 can be initiated for the NAK 534 reporting both the corrupted packets 504-505 of the hole. The NAK disable timer 544 is said to be associated with both the lost PDU 504 and the lost PDU 505, thus preventing further NAKs from being sent for either of these two lost PDUs until the NAK disable timer 544 expires.

Regarding the transmission of the status report, and in particular, regarding the timing of transmitting the NAKs of the corrupted packet, in general, a status report will be sent upon receipt of one of the interrogations sent by the transmitting entity. However, in various embodiments, a status report containing a NAK may be sent upon detection of the corrupted PDU without waiting for an interrogation. For example, in W-CDMA, the "lost PDU indicator" option can be configured to wait for an interrogation to send a NAK for a newly discovered corrupted PDU. Even if the option is configured to send NAKs without waiting for an inquiry, a pending state inhibit timer can also delay the NAK.

Figure 6A illustrates the interrelationship between a NAK inhibit timer, an ACK inhibit timer, and a state inhibit timer, in accordance with the present invention. The figure depicts three types of timers: NAK disable timers 641-642, state disable timer 650, and ACK disable timers 661-663. These NAK prohibit timers are dedicated to NAK. This means that after a NAK is sent, until the NAK disable timer expires, it will block the transmission of any additional NAKs for the corrupted PDU associated with the NAK disable timer, but it will not prevent the transmission from being sent for other losses. NAKs of PDUs. The NAK-specific NAK disable timer associated with a lost PDU does not prevent a NAK from being sent for a different lost PDU. In general, the NAK disable timer can be set to slightly more than one RTT (eg, sometimes set to be 20-100 ms longer than an RTT). On the other hand, the status prohibit timer is not NAK-specific. A state inhibit timer prevents any status report from being sent until it times out. Therefore, if there is a NAK to be sent, the NAK will be delayed until the pending state disable timer expires. The state inhibit timer can be set to any length of time, but in accordance with various embodiments of the present invention, it is typically set to be slightly shorter than the duration of an RTT. In this manner, the state variable VR(R) of the last sequentially received sequence number (representing the beginning of the receiver window) is frequently updated, thereby moving the RLC window in a timely manner. The ACK timer blocks transmissions including only one ACK instead of a NAK status report until the pending ACK timer expires. However, the ACK timer does not block or delay status reporting containing NAKs. Further, in some embodiments, if there is a NAK to be sent, the status report will be sent (because the ACK timer does not delay the NAKs) and also because it will be sent anyway, the status report by the NAK prompt is also An ACK can be included.

When receiving PDUs, the receiving entity may detect a corrupted packet (e.g., PDUs 601 and 602) from time to time depending on the channel conditions. In some embodiments, a NAK may be sent as soon as an interrogation has not been received from the transmitter, while in other embodiments, the receiving entity may wait until the next interrogation is received to initiate a NAK transmission. However, in any of the above embodiments, if there is a valid pending status prohibit timer, a status report containing a NAK will not be sent. In the example shown in FIG. 6A, since the state prohibit timer 651 is pending, the NAK 631 for the corrupted PDU 601 is not immediately transmitted. The state inhibit timer 651 delays the NAK 631 for the corrupted PDU 601 until it times out at time 691. It should be noted that at time 691, the ACK inhibit timer 661 is pending. However, since the ACK inhibit timer does not delay or affect the transmission of the NAKs, even if the ACK disable timer 661 is currently running, the NAK for the corrupted packet 601 will also be transmitted. Further, in some embodiments, even if the ACK timer 661 is active, the status report containing the NAK 631 also includes an ACK. Sending an ACK with this status report does not increase overhead, as this status report initiated for NAK 631 will be sent anyway. In some embodiments, an ACK inhibit timer may be reset if an ACK is accompanied by a NAK in a status report transmitted during an ACK inhibit timer.

In conventional systems, the state inhibit timer is generally equal to or slightly larger than the RTT. In accordance with various embodiments disclosed herein, the state inhibit timer may be much shorter than the duration of the RTT, typically a short multiple (eg, state disable timer 650). 6A depicts an example scenario in which a NAK disable timer (641-642) is approximately two and a half times longer than the state inhibit timer, and the ACK inhibit timer is depicted in the figure as being the state inhibit timer. Three times longer. By having the state inhibit timers be much shorter than the RTT, the various embodiments are capable of updating the state variable VR(R) for the last sequentially received sequence code, and thus disabling the RLC window with a small delay Move before.

Figure 7 depicts a method for link control in accordance with various embodiments of the present invention. The method begins at 701 and continues to where 705 of a PDU is detected. In 705, it is contemplated that the receiving entity receives data from a transmitting entity within a predetermined time period, time slot, or TTI (transmission time interval). For example, a receiving entity (e.g., UE 210 of FIG. 2) can be expected to receive a data packet from a transport entity (e.g., Node B 220) in a particular time slot (e.g., time slot 501 of FIG. 5A). The receiving entity is not necessarily limited to a mobile station. The receiving entity can be a fixed station (e.g., Node B 220 or landline telephone 260 of Figure 2), and the transmitting entity can be another fixed station or a mobile station. A particular station participating in two-way communication will be a receiving entity of certain PDUs and a transmitting entity of another PDUs. The method continues from 705 to 707 when detecting if a PDU has been received.

In 707, the receiving entity determines that the PDU was correctly received (e.g., 511 or 580 of Figure 5) and is also corrupted (e.g., 501-505). A properly received packet may be a retransmitted packet (e.g., 511-515) or may be a first transmitted packet, an initial transmission (e.g., 580 of Figure 5 and other unlabeled packets). Further, a properly received packet may be the result of a packet that has been corrupted but has been recovered using error correction. A corrupted packet (sometimes referred to as a lost packet) may contain erroneous or untranslatable material or may not be received at all. As part of 707, in some embodiments, the receiving entity may implement an error check to determine if the PDU is corrupted. The error check may involve any error checking routine or any routine or algorithm of the algorithm (eg, a redundancy check (eg, and check); a cyclic redundancy check (CRC); a frame check sequence (FCS); or an error correction code (ECC) (eg, Hamming code, Li De-Solomon code, Li De-Miller code, binary Gray code, whirling code, turbo code) Or other similar types of error detection or detection/correction schemes). In block 707, verifying that the PDUs are correctly received or corrupted may require actions such as performing a channel measurement or received power measurement; an implicit estimation of the received quality of the mobile unit; or being familiar with Any other similar type of routine or test known to the skilled artisan for receiving errors. If it is determined in 707 that the PDU has been corrupted, then the method continues to 709 of the NAK procedure. Block 709 of the NAK program will be discussed in more detail in FIG.

After completing block 709 of the NAK procedure, the method continues to 711 to execute the ACK counter procedure. Some embodiments may perform an ACK counter procedure, although other embodiments do not. If the ACK counter procedure has not been executed, the method proceeds directly from 709 to 703 where it is determined if the communication has ended. For the embodiment of executing an ACK counter program, the program of block 711 is executed. The ACK counter procedure for block 711 will be discussed in more detail in FIG. After the ACK counter procedure has been completed, the method continues to 703.

Returning to 707, if it is determined that the PDU has been received correctly, the method continues to 713 where it is determined that the initial transmission of the received PDU by a new data is a retransmission of previously corrupted data. If the PDU is determined to be new, the method continues to 715 of the ACK procedure. If it is determined in 713 that the received PDU is a retransmission of a previously corrupted data, the method continues to 719. In 719, the NAK disable timer associated with the retransmission is stopped or removed (if it is still running). Since the retransmitted packet has been received, any NAKs associated with the retransmitted packet that may have been queued for transmission are no longer needed, and therefore are discarded and are no longer transmitted. The method continues from 719 to 715. This ACK program 715 will be explained in more detail in FIG. The ACK of the ACK program 715 either causes an ACK to be transmitted or if an ACK inhibit timer is valid, causing an ACK queue to wait for transmission when the ACK inhibit timer expires.

Once the ACK procedure is completed 715, the method continues to 717 to determine if there are any expired NAK disable timers based on previously corrupted packets that have not received their retransmissions. Although the NAK disable timer can be set to any value within the receiving entity, it is generally advantageous to set the NAK disable timer to be slightly greater than one round trip time (RTT). An RTT is an expected time taken by a NAK to be transmitted back to the transport entity, processed by the transport entity, and then caused by the transport entity to transmit a retransmission to the receiving entity. The RTT value may depend on channel conditions to some extent, or in a landline scenario, depending on the communication path of the signal. Setting the NAK disable timer to slightly more than one RTT tends to avoid spurious retransmissions, that is, avoiding one that is caused by sending an additional NAK despite a retransmission initiated by an earlier NAK. Or multiple additional unnecessary retransmissions. Therefore, the NAK disable timer is typically set to about one RTT, or slightly larger than one RTT. For example, the NAK disable timer can be set to an RTT plus an additional transmission time interval (TTI), an RTT+2xTIIs, an RTT+3xTIIs, or possibly a longer time set value (if the conditions warrant the set value). In some embodiments, the NAK inhibit timer set value can be measured as a percentage of the RTT, such as 110% or a similar percentage. Regardless of the value set by the timer, once the NAK inhibit timer of a particular corrupted PDU has expired, another NAK can be sent for the particular corrupted PDU. Although the transmission of the second NAK (or subsequent NAKs) may occasionally result in a false retransmission, the delay introduced by the NAK disable timer to transmit additional NAKs will significantly reduce the occurrence of spurious retransmissions.

If it is determined in 717 that there is an expired NAK disable timer that has not received (or has corrupted) its retransmission, the method will continue from 717 along the "yes" branch to 721. In some systems, there may be a limit on the number of NAKs sent for a particular corrupted packet to, for example, avoid stalling the communication. In such systems, block 721 determines the maximum number of NAKs that have been sent for the packet. If not, the method will continue from 721 along the "no" branch to 709 to execute the NAK procedure and initiate another NAK for the corrupted packet. If it is determined in 721 that the maximum number of retransmissions has been sent, the method will continue from 721 along the "yes" branch to execute the error procedure in 723. The error program may require an error report to the system and an error recovery routine or data interpolation that may use data from an adjacent packet as a stop gap measure to fill the PDU hole. Alternatively, the damaged time slot can be left blank. Once the error procedure is completed in 723, the method continues to 703.

Returning to 717, if it is determined that there is no expired NAK disable timer for the previously transmitted NAKs, the method continues from 717 to 703 along the "NO" branch. In 703, it is determined whether the communication has ended, for example, whether the data transmission has been completed, or whether one or other users have disconnected or hanged up. If it is determined in 703 that the communication has not ended, the method proceeds from 703 along the "No" path to 705 to detect whether a PDU was received in the next time slot. If the communication has ended, the method will continue from 703 along the "Yes" path to 725 to execute the routine to end the communication and the method ends.

Figure 8 depicts a method for initiating NAKs as part of link control in accordance with various embodiments of the present invention. In particular, Figure 8 depicts details of the NAK procedure of block 709 of Figure 7. Thus, 801 of FIG. 8 is generally implemented after 707 or 721 of FIG. If 801 is implemented after 721, there will be no NAK-specific valid NAK disable timer for the corrupted data packet being processed, since it has been determined in 717 that the previous NAK disable timer has expired. In 801, it is determined whether there is a valid NAK inhibit timer that prevents the NAK from being sent in response to detecting a corrupted packet in 707. The absence of a pending NAK disable timer is extremely common because the corrupted packet or the initial transmission of the NAK disable timer or the corrupted packet is expired or nearly expired. Retransmission. For those cases in which the receiving entity is capable of detecting the identity of a corrupted packet as a retransmission identity, the receiving entity may terminate the NAK inhibit timing because it is no longer required to further delay sending another NAK. The remaining time on the device.

If it is determined in 801 that there is a valid NAK disable timer, the method will continue from 801 along the "yes" branch to 803 to queue the NAK for a later time after the NAK disable timer expires. In some embodiments, the NAK may be sent due to expiration of the NAK disable timer. However, in other embodiments, when it is detected that there is a pseudo-transmit NAK, the system may check for a pending NAK disable timer and The NAK is sent if no NAK prohibit timer is found. Once the NAK queue is available for transmission in 803, the method continues to 703 of FIG. If it is determined in 801 that there is no valid NAK inhibit timer, the method continues from 801 to 805 along the "NO" branch.

A determination is made in 805 as to whether there is a pending status prohibit timer that will prevent the transmission of any status report containing NAKs. The state inhibit timer (which is not dedicated to any particular packet or NAKs) is typically set to be slightly shorter than an RTT to move the RLC window forward more sensitively. Typically, the state inhibit timer can be set by one-half to one-tenth of an RTT. Under extreme conditions, the state inhibit timer should be set to no more than one RTT or no less than one time slot width. If it is determined in 805 that a state inhibit timer is active, the method continues from 805 along the "yes" branch to 803 to queue the NAK for transmission when the state disable timer is no longer running. If it is determined in 805 that there is no valid state inhibit timer, the method will continue from 805 to the "NO" branch to 807. In block 807, a NAK is sent from the receiving entity to the transmitting entity, and the method continues to 703 of FIG.

9 depicts a method for initiating ACKs as part of link control in accordance with various embodiments of the present invention. In particular, FIG. 9 depicts details of the ACK procedure of block 715 of FIG. Thus, 901 of FIG. 9 is typically performed at 713 or 719 of FIG. 7. In 901, it is determined how far the RLC window needs to be moved, that is, until which time slot has correctly received or otherwise counted all PDUs (including Retransmission). The state variable VR(R) represents the sequence number of the last received sequence that marks the beginning of the receiver window. Block 901 determines, for example, how far the window can be moved based on the value of the state variable VR(R). The time slot or HARQ example of the last correctly received consecutive PDU is an example of an ACK to be sent for it. In a status report, only one PDU needs to be acknowledged. Generally, according to a pre-arranged convention, it is assumed that all PDUs before a PDU specified in the ACK have been correctly received. In some other embodiments, this may be accomplished in a more cumbersome manner by listing all received PDUs rather than specifying the PDUs that are used to move the window correctly forward. In 901, once it is determined how far to move the window and which PDU to confirm, the method continues to 903.

In 903, it is determined whether there is a valid ACK inhibit timer. Depending on the parameters of the communication and the need for timely data, the ACK inhibit timer can be set to any of a wide range of values within the receiving entity. For example, for a relatively high data rate, the ACK inhibit timer can be set to a value slightly shorter than one RTT to move the receiver window forward more sensitively. On the other hand, for a relatively low data rate, the ACK inhibit timer can be set to a value longer than the NAK disable timer (which is typically set to slightly more than one RTT), especially if not urgently needed Move the receiver window before. Further, if an ACK counter is constructed, the value for the ACK inhibit timer can be set to a relatively large value because the ACK inhibit timer is used as a stop gap measure.

If, in 903, an ACK inhibit timer is asserted, the method continues from 903 to 905 along the "yes" branch to queue the ACK for transmission after the ACK inhibit timer expires. In some embodiments, the ACK may be sent due to expiration of the ACK inhibit timer, while in other embodiments, when detecting the presence of a pseudo-transmit ACK, the receiving entity may check a pending ACK inhibit timer and The ACK is sent if no ACK inhibit timer is found. Once the ACK is queued for transmission in 905, the method continues to 717 in FIG. If it is determined in 903 that there is no valid ACK inhibit timer, the method continues from 903 to 907 along the "NO" branch.

A determination is made in 907 as to whether there is a pending state inhibit timer that will prevent the transmission of any status report containing the ACK. If it is determined that a state inhibit timer is currently running, the method continues from 907 to 905 along the "yes" branch to queue the ACK for transmission when the state inhibit timer is no longer running. If it is determined in 907 that there is no valid state inhibit timer, the method continues from 907 to 909 along the "NO" branch. In block 909, an ACK is sent from the receiving entity to the transmitting entity, and the method continues to 717 of FIG. In 909 or in 905, if it is determined that a new ACK inhibit timer set value is suitable for the current condition, it is transmitted to the transport entity by ACK of 909 or 905.

10 depicts an ACK counter procedure that can be used to adjust the ACK reporting period in accordance with various embodiments described herein. In particular, Figure 10 depicts the ACK counter procedure for block 711 of Figure 7. Block 1001 of Figure 10 is typically executed after 709 of Figure 7. If an ACK counter is valid, the ACK inhibit timer can be set to a relatively long value because the ACK reporting function is primarily initiated by the ACK counter.

The ACK counter modifies the ACK reporting period to accommodate the current data transmission rate, thereby helping to keep the RLC window effectively sliding forward. In the absence of an ACK counter, when the transmission condition changes, for example if the transmission data rate changes, the transmitting entity will transmit a new ACK inhibit timer value to the receiving entity. If the ACK inhibit timer is not adjusted accordingly when the data rate changes, the RLC throughput may be limited or may even stall. For example, if the ACK inhibit timer is set to a relatively large value and the data rate suddenly increases, the RLC throughput will be limited. For the same reason, for example, if the ACK inhibit timer is set to a relatively low value and the data rate suddenly decreases, a large communication may occur that is not necessary in the opposite direction from the receiving entity to the transmitting entity. load.

To avoid setting the ACK inhibit timer to a low efficiency value for a pair of transmitted data rates, various embodiments disclosed herein have an ACK counter variable that allows the receiving entity to track the self-reported VR The amount by which the last ACK value is increased after the (R) value. Since the state variable VR(R) represents the last sequence number received in sequence, the ACK counter indicates the extent to which the receiver window is filled. If the ACK counter passes a predetermined threshold, the ACK can be reported by means of the transmitted next status report, thereby avoiding the aforementioned performance deficiencies. The threshold can be defined as an increment associated with various data rates or as a percentage of the configured receiver window size.

The state variable VR(R) represents the last sequential PDU received at the receiving entity. The state variable VR(R) increases each time another consecutive PDU is correctly received at the receiving entity. In 1001 of Fig. 10, it is determined whether VR(R) has reached a threshold. The threshold can be defined as a percentage of the configured receiver or RLC window size, for example, from 10% to 50% of the receiver window. Alternatively, a percentage of other smaller or larger window sizes suitable for link control conditions may be used, for example up to 80% or more of the window size. If in 1001, it is determined that VR(R) has reached the threshold, the method continues from 1001 to 1003 along the "Yes" path. In 1003, it is determined that a new ACK inhibit timer set value is suitable for the communication condition and then transmitted to the transport entity by an ACK. After the ACK containing the adjustment to the ACK inhibit timer has been sent from the receiving entity to the transmitting entity, the method continues from 1003 back to 703 of FIG. One advantage of using this ACK counter is that it is now easy to adapt the frequency of the ACK report to the rate condition.

For fairly high transmission data rates, ACKs will be reported more frequently, allowing the RLC window to move forward faster. If the rate is greatly reduced, adjustments can be made to report ACKs less frequently, thereby reducing the communication load in the opposite direction. To avoid situations in which the ACK value is never reported, the ACK inhibit timer described in connection with FIG. 9 can be maintained. Keeping the ACK reporting period set to a fairly large value does not significantly increase the burden of the system's feedback resources. In a sense, when the ACK counter is enabled, the ACK inhibit timer can be considered to be one of the maximum limit values for the ACK reporting period. Similarly, for the highest data rate, the state prohibit timer can be used to limit the ACK reporting frequency to the lower end.

The drawings are intended to be illustrative of the invention and are illustrative of the principles of the invention. The inventive activities shown in the block diagrams of the methods for implementing the figures may be performed in an order different from that shown in the drawings or may be omitted in their entirety. For example, in FIG. 7, a determination (703) as to whether the communication is ending may occur while or after detecting the next PDU (705). Similarly, in some embodiments, the ACK counter program (711) may be implemented before the NAK program (709), and in other embodiments, after the next PDU detection (705), or These embodiments are not implemented at all.

Those skilled in the art should be aware that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields, or particles, or any combination thereof. Those skilled in the art should further appreciate that the various illustrative logic blocks, modules, circuits, and algorithms described in connection with the embodiments disclosed herein can be constructed as electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps are described above based on functionality. Whether a function is built as hardware or software depends on the specific application and design constraints imposed on the overall system. Skilled artisans are capable of <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt; </ RTI> <RTIgt;

The various illustrative logic blocks, modules, and circuits described herein in connection with the specific embodiments of the present invention may be implemented by a general purpose processor, digital signal processor (DSP), dedicated integrated circuit (ASIC), field programmable gate array (FPGA). Or other programmable logic devices, discrete gate or transistor logic circuits, discrete hardware components, or any combination thereof, designed to implement the functions described herein, constructed or implemented. A general purpose processor can be a microprocessor, but the alternative is that the processor can be any conventional processor, controller, microcontroller or state machine. A processor can also be constructed as a combination of a plurality of computing devices, for example, a combination of a DSP and a microprocessor, a combination of a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any Other such configurations.

The steps of the method and algorithm described herein in connection with the embodiments of the present invention may be directly included in a hardware, a software module executed by a processor, or a combination of the two. A software module can reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a scratchpad, a hard disk, a removable disk, a CD-ROM or the like Any other form of storage medium is known in the art. An example storage medium is coupled to the processor to enable the processor to read information from the storage medium and to write information to the storage medium. Alternatively, the storage medium can be integrated with the processor. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and the storage medium can reside as a separate component in a user terminal.

The term "example" as used herein means "serving as an instance, instance, or illustration." The various embodiments and features described herein as "exemplary" are not necessarily to be construed as preferred or preferred.

The above description of the disclosed embodiments is intended to enable any person skilled in the art to make or use the invention. A variety of modifications to the embodiments are readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but the broad scope of the principles and novel features disclosed herein.

101-105. . . Lost packet (signal, time slot, corrupted packet)

111-115. . . Retransmit packet/retransmission

120. . . Inquiry (signal)

131-133. . . NAK (negative recognition, NAK transmission)

141-143. . . State inhibit timer

200. . . Typical wireless network architecture (wireless system)

210. . . User equipment (UE)

207. . . Processor or another logic

209. . . Memory

211. . . Encoder/decoder circuit

213. . . antenna

215. . . Receiver/transmitter circuit

220. . . Base station (node-B)

221. . . processor

223. . . Memory

225. . . Encoder/decoder

227. . . Receiver/transmitter circuit

230. . . Radio Network Controller (RNC)

240. . . Radio Network Subsystem (RNS)

250. . . Core network (fixed network)

260. . . Landline telephone (fixed station)

401-409. . . Identifier (status report)

411. . . Destroyed PDU (block, hole)

413. . . Destroyed PDU (block, hole)

415. . . Destroyed PDU (block, hole)

421-427. . . Status inhibit timer (disable timer)

431. . . delay

433. . . delay

435. . . delay

501-505. . . Lost packets (time slots, signals, corrupted packets, corrupted PDUs)

511-515. . . Retransmission packet

520. . . Transport entity (signal)

531-534. . . NAK

541-544. . . NAK disable timer (state disable timer)

601. . . Destroyed PDU (destroyed packet)

631. . . NAK

641-642. . . NAK prohibit timer

650. . . State inhibit timer

651. . . State inhibit timer

661-663. . . ACK inhibit timer

691. . . time

1A and 1B depict a conventional scheme for recovering lost or corrupted packets; FIG. 2 depicts a network architecture for supporting communication between wired and wireless stations in accordance with various embodiments of the present invention; FIG. 3 depicts a mobile station and a fixed Details of the base station; Figure 4 illustrates the delay affecting the retransmission of lost PDUs when each RTT transmits only no more than one status report; Figures 5A and 5B depict a use of a NAK disable timer recovery in accordance with various embodiments of the present invention. Schemes for Losing or Destroying Packets; Figures 6A and 6B depict a scheme for recovering lost or corrupted packets using a NAK inhibit timer, an ACK inhibit timer, and a state inhibit timer in accordance with various embodiments of the present invention; A method for link control in accordance with various embodiments of the present invention; FIG. 8 depicts details of a method for controlling NAKs in accordance with various embodiments of the present invention; FIG. 9 depicts one of the various embodiments of the present invention for controlling ACKs Details of the method; and FIG. 10 depicts an ACK counter procedure that can be used to adjust the ACK reporting period in accordance with various embodiments of the present invention.

601. . . Destroyed PDU (destroyed packet)

602. . . Destroyed PDU (destroyed packet)

631. . . NAK

641. . . NAK prohibit timer

642. . . NAK prohibit timer

650. . . State inhibit timer

651. . . State inhibit timer

661. . . ACK inhibit timer

662. . . ACK inhibit timer

663. . . ACK inhibit timer

691. . . time

Claims (34)

A method of controlling a communication link, comprising: detecting a corrupted packet from a transmitting entity at a receiving entity; transmitting a negative acknowledgement (NAK) to the transmitting entity; and initiating transmission of the NAK A NAK inhibit timer associated with the corrupted packet and associated with any subsequent consecutive corrupted packets, wherein each of the non-contiguous subsequent corrupted packets is significantly associated with a separate NAK inhibit timer Corresponding; further wherein the NAK inhibit timer prevents further NAK from being sent for the corrupted packet until the NAK inhibit timer has expired. The method of claim 1, wherein the NAK inhibit timer allows other NAKs to be sent for other corrupted packets before the NAK inhibit timer expires. The method of claim 1, wherein the NAK inhibit timer is initially set to run at least one round trip time (RTT). The method of claim 1, wherein the corrupted packet is a first corrupted packet, the NAK is a first NAK, and the NAK inhibit timer is a first NAK disable timer, the method further comprising: Sending a second NAK associated with a second corrupted packet to the transmitting entity before the expiration of the first NAK prohibition timer associated with the first corrupted packet; and setting one and the second corrupted The second NAK prohibit timer associated with the packet. The method of claim 1, further comprising: receiving an inquiry from the transmitting entity at the receiving entity; and transmitting a status report from the receiving entity to the transmission before the NAK prohibit timer expires Entity; wherein the status report does not include a further NAK associated with the corrupted packet. The method of claim 4, wherein the first NAK and the second NAK are both transmitted to the transmitting entity in a wireless manner. The method of claim 4, wherein the first NAK and the second NAK are both wirelessly transmitted to the transport entity in accordance with a Wideband Coded Multiple Access (W-CDMA) protocol. The method of claim 1, further comprising: initiating a state inhibit timer having a shorter duration than the NAK inhibit timer before the detecting of the corrupted packet; and delaying the NAK The transmission does not expire until the state prohibits the timer. The method of claim 8, further comprising: transmitting a status report; wherein the status report includes an acknowledgement (ACK) and the NAK; and wherein the status prohibit timer delays the status report from being sent until the status prohibit timer Expiration. According to the method of claim 1, further comprising: starting an ACK inhibit timer; and delaying transmitting a ACK status report until the ACK inhibit timer Expiration. The method of claim 1, further comprising: initiating an ACK counter after transmitting a first ACK from the receiving entity to the transmitting entity; and transmitting a second ACK if the ACK counter reaches a predetermined threshold. The method of claim 11, wherein the predetermined threshold is defined as a percentage of a receiver window width. The method of claim 1, wherein the corrupted packet is a first corrupted packet and the next consecutive packet is a second corrupted packet, the method further comprising: transmitting the NAK to report the first and the first The transport entity of the two corrupted packets; wherein the NAK disable timer is associated with both the first and second corrupted packets. A computer readable medium comprising a method of controlling a communication link, the method comprising: detecting a corrupted packet from a transmitting entity at a receiving entity; transmitting a NAK to the transmitting entity; and The transmission of the NAK initiates a NAK disable timer associated with the corrupted packet and associated with any subsequent consecutive corrupted packets, wherein each of the non-contiguous subsequent corrupted packets is significantly associated with one NAK inhibit timers are respectively associated; further wherein the NAK disable timer blocks for the corrupted packet A further NAK is sent until the NAK disable timer expires. The computer readable medium according to claim 14, wherein the NAK inhibit timer allows other NAKs to be sent for other corrupted packets before the NAK inhibit timer expires. The computer readable medium according to claim 14 wherein the NAK inhibit timer is initially set to run at least one RTT. The computer readable medium according to claim 14, wherein the corrupted packet is a first corrupted packet, the NAK is a first NAK, and the NAK inhibit timer is a first NAK disable timer, the method further The method includes: transmitting, to the transmitting entity, a second NAK associated with a second corrupted packet before expiration of the first NAK prohibition timer associated with the first corrupted packet; and setting a first The second NAK disable timer associated with the second corrupted packet. The computer readable medium of claim 14, further comprising: receiving, at the receiving entity, an interrogation from the one of the transmitting entities; and reporting a status from the receiving entity prior to expiration of the NAK prohibition timer Sent to the transmitting entity; wherein the state does not include the further NAKs associated with the corrupted packet. The computer readable medium of claim 17, wherein both the first NAK and the second NAK are wirelessly transmitted to the transmitting entity. The computer readable medium according to claim 17, wherein the first NAK and the second NAK are based on a Wideband Coded Multiple Proximity (W-CDMA) protocol Wirelessly transmitted to the transport entity. The computer readable medium of claim 14, further comprising: initiating a state inhibit timer having a shorter duration than the NAK disable timer prior to the detecting of the corrupted packet; The transmission of the NAK is delayed until the state prohibit timer expires. The computer readable medium according to claim 21, further comprising: transmitting a status report; wherein the status report includes an ACK and the NAK; and wherein the status prohibit timer delays transmitting the status report until the status prohibit timer has Expiration. The computer readable medium according to claim 21, further comprising: initiating an ACK inhibit timer having a duration longer than the NAK inhibit timer; and delaying transmitting a unique ACK status report until the ACK inhibit timer Expiration. The computer readable medium of claim 14, further comprising: initiating an ACK counter upon transmitting a first ACK from the receiving entity to the transmitting entity; and if the ACK counter reaches a predetermined threshold, then Send a second ACK. The computer readable medium according to claim 24, wherein the predetermined threshold is defined as a percentage of a receiver window width. A receiving entity configured to receive a packet by a communication link, the receiving entity comprising: a receiver circuit configured to detect a corrupted packet received from a transmitting entity; a transmitter circuit configured to send a NAK to the transmitting entity; and a NAK inhibit timer, which is significant Associated with the corrupted packet and associated with any subsequent consecutive corrupted packets, the NAK inhibit timer is initiated in response to the NAK being sent, wherein each of the non-contiguous subsequent corrupted packets is significantly Associated with a separate NAK inhibit timer; wherein the NAK disable timer prevents further NAK from being sent for the corrupted packet until the NAK disable timer expires, and wherein the NAK disable timer allows the timer to be disabled at the NAK Send other NAKs for other corrupted packets before the expiration. The receiving entity of claim 26, wherein the transmitter circuit wirelessly transmits the NAK to the transmitting entity. According to the receiving entity of claim 26, further comprising: a state inhibit timer configured to have a shorter duration than the NAK inhibit timer; wherein, once activated, the state inhibit timer is configured to The transmission of the NAK is delayed until the state prohibit timer expires. According to the receiving entity of claim 26, further comprising: an ACK inhibit timer configured to have a longer duration than the NAK inhibit timer; wherein, once activated, the ACK inhibit timer is configured to delay A ACK status report is sent until the ACK inhibit timer expires. According to the receiving entity of claim 26, further comprising: an ACK counter configured to initiate upon transmitting a first ACK from the receiving entity to the transmitting entity; wherein the ACK counter is configured to A second ACK is sent if the ACK counter reaches a predetermined threshold. According to the receiving entity of claim 30, wherein the predetermined threshold is defined as a percentage of a receive window width. An apparatus for controlling a communication link, comprising: means for detecting a corrupted packet from a transmitting entity at a receiving entity; means for transmitting a negative acknowledgement (NAK) to the transmitting entity; And means for initiating a NAK inhibit timer associated with the corrupted packet and associated with any subsequent consecutive corrupted packets in response to the transmission of the NAK, wherein the non-continuous subsequent corrupted packets are Each is significantly associated with a separate NAK inhibit timer; further wherein the NAK inhibit timer prevents further NAKs from being sent for the corrupted packet until the NAK inhibit timer has expired. The apparatus of claim 32, wherein the NAK inhibit timer allows other NAKs to be sent for other corrupted packets before the NAK inhibit timer expires. The apparatus of claim 32, wherein the NAK inhibit timer is initially set to run at least one round trip time (RTT).