摘要:
A method of scheduling packets for transmission over the air interface of a UMTS Terrestrial Radio Access Network (UTRAN) in the case where a pair of Radio Network Controllers (RNCs) are acting as separate serving and controlling (drift) RNCs for a mobile terminal. The method comprises sending from the controlling RNC to the serving RNC, allocated scheduling priorities together with packet sizes accepted for transmission with those priorities by the controlling RNC. Subsequently the serving RNC send to the controlling RNC, packets of sizes accepted by the serving RNC together with respective allocated priorities.
摘要:
In a UMTS Terrestrial Radio Access Network (UTRAN), a method of switching from a current common channel to a dedicated channel for a UE. The method comprises estimating the round trip delay for data packets travelling between the UE and a peer node with which the UE is communicating. The product of the estimated round trip delay and the bandwidth of the common channel or the dedicated channel is determined and a threshold defined on the basis of that product. A switch from the common channel to a dedicated channel is initiated when the fill level of the RLC buffer(s) in the UTRAN for the UE reaches or exceeds said threshold.
摘要:
A method of controlling the sending of data packets from a Base Station (BS) of a Radio Access Network (RAN) to a UE, where the BS is one of a set of BSs transmitting identical data to the UE and each said data packet has a sequence number. The method comprises implementing at the BS an Automatic Repetition reQuest (ARQ) mechanism for resending data packets erroneously received by the UE and, upon receipt of an ARQ status message from the UE, advancing a transmission window of the BS so that its lower region covers the packet having the highest sequence number for which an ARQ acknowledgement has nor yet been received. Where a single BS is transmitting in the downlink direction, and a soft handover set exists for an uplink reverse channel, downlink sending buffers of the BSs of the soft handover set may be synchronized by the exchange of ARQ messages between BSs.
摘要:
By adaptively relocating a transmitting point between a base station and a base station controller, e.g., an RNC, optimal ARQ performance is achieved. The adaptation may be based on one or more of many factors such as the distance between a network element and a user equipment. As one example, for a mobile radio near a base station, the transmitting point where the ARQ protocol terminated in the radio network is located in that base station so that ARQ packet retransmissions are performed quickly. For a mobile radio in or about to be in soft handover, the transmitting point where the ARQ protocol terminated in the radio network is located in a base station controller coupled to the base stations involved in (or soon will be involved in) soft handover so that robust ARQ packet retransmissions are provided.
摘要:
In a method for the transmission of data packets (D) from a transmitter (TR) to a receiver (RE) identification of transmitted data packets are stored. Defective data packets (D) are detected by the receiver (RE), status messages (S) which request defective data packets for retransmission are sent from the receiver (RE) to the transmitter (TR) and retransmissions of requested data packets are performed according to the status messages (S). The transmitter (TR) evaluates a first status message (S11) with an identification of at least one first requested data packet and retransmits the first data packet. The transmitter (TR) then initializes a timing unit according to the retransmission of the first data packet, wherein the timing unit or a threshold for the timing unit is attributable to the first data packet. When the transmitter evaluates a further status message (S12) and detects at least one further data packet that is requested for a retransmission, it selects the further data packet if the timing unit has reached the threshold or if the identification of the further data packet is different from the identification of the first data packets. Only the selected data packets are retransmitted. A transmitter and software programs embodying the invention are also described.
摘要:
A method of handling the transmission of Radio Link Control (RLC) Protocol Data Units (PDUs) from a Radio Access Network (RAN) of a mobile telecommunications system to User Equipment (UE). At a Gateway of the RAN, RLC Service Data Units (SDUs) are segmented into RLC PDUs for transmission to one or more Base Stations (BSs) of a set of BSs belonging to a handover link set. RLC PDUs received from one or more of those BSs are combined into RLC SDUs for transmission to a core network of the system. Each of the BSs buffers the RLC PDUs received from the Gateway and/or the UE. An Automatic Repetition Request (ARQ) mechanism is implemented at each of the BSs to facilitate reliable transmission of RLC PDUs between the UE and the Gateway.
摘要:
In a wireless communication network where base stations receive protocol data units (PDUs) from mobile stations for decompression and deciphering for ordered, sequential transfer as service data units (SDUs) to an associated core network, the teachings presented herein provide a method of supporting seamless handover of a mobile station from a source base station to a target base station. By way of example, the teachings herein apply to a network based on the E-UTRA specifications, as promulgated by the 3GPP. However, that example is non-limiting, as the teachings herein apply to any network that employs in-sequence data delivery and duplicate data detection at handover. Broadly, the source base station forwards out-of-sequence SDUs and corresponding sequence number information to the target base station in support of seamless handover, and the target base station uses that information to request retransmissions as needed for packet reordering.
摘要:
Methods, apparatus, and systems for measuring, on a per-QoS-class basis, the average number of user devices active on the uplink of a wireless communication system are disclosed. In an exemplary method, a number of mobile terminals with buffered data for transmission to a base station is estimated based on received buffer status reports. An estimated quantity of active mobile terminals is calculated, based on the received buffer status reports and a number of mobile terminals for which a semi-persistent scheduling grant has been granted. In some embodiments, the estimated quantity of active mobile terminals is estimated on a per-traffic-class basis, in which case the technique includes calculating first and second estimated quantities, corresponding to mobile terminals having active data bearers for first and second traffic classes, respectively, based on the received buffer status reports and the number of mobile terminals for which a semi-persistent scheduling grant has been granted.
摘要:
A method and apparatus according to the present invention addresses and/or prevents lost protocol synchronization in HARQ systems caused by ACK/NACK errors. One embodiment detects lost synchronization errors for NDI-based retransmission protocols and restores synchronization by sending an explicit RESET message. In response to the RESET message, the transmitter aborts the transmission of a current PDU and transmits a new PDU and corresponding NDI. Another embodiment prevents protocol synchronization errors by sending scheduling grants on a packet by packet basis. The receiver sends a subsequent explicit scheduling grant to the transmitter based on an error evaluation of a received PDU. The transmitter will not send the next PDU unless it receives the subsequent explicit scheduling grant.
摘要:
A method for sending buffer status information includes checking if a quality of service (QoS) parameter is defined for a first logical channel and at least one condition of the set of predetermined conditions associated with a logical channel group is fulfilled. If the QoS parameter is defined and at least one condition of the set is fulfilled, the method includes setting a number of bits in a media access control header according to a first semantic. The bits carry buffer status information, and the first semantic—is based on the QoS parameter of the first logical channel. Otherwise, the method includes setting the number of bits carrying the buffer status information according to a second semantic that is based on an amount of data available for transmission across the logical channel group.