HK1194594A - Determinative segmentation resegmentation and padding in radio link control (rlc) service data units (sdu) - Google Patents

Description

Deterministic segmentation, re-segmentation and padding in Radio Link Control (RLC) Service Data Units (SDUs)

The present application is a divisional application of the 'deterministic segmentation, re-segmentation and padding in Radio Link Control (RLC) Service Data Units (SDUs)' inventive patent application No. 200980112012.0, filed 3.31.2009.

Claim priority in accordance with 35 th article 119 of the American code

The present patent application claims priority from us provisional application serial No. 61/041,201, entitled "method and Apparatus for minimizing fragmentation, Re-fragmentation and Padding in LTE", filed 3/31/2008, assigned to the assignee of the present application and hereby incorporated by reference.

Technical Field

The exemplary and non-limiting aspects described herein relate generally to wireless communication systems, methods, computer program products, and devices and, more specifically, relate to techniques for deterministic techniques for segmentation, re-segmentation, and padding of Radio Link Control (RLC) Service Data Units (SDUs).

Background

Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Orthogonal Frequency Division Multiple Access (OFDMA) systems.

Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. Each terminal communicates with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. The communication link may be established via a single-input single-output (SISO) system, a multiple-input single-output (memo) system, or a multiple-input multiple-output (MIMO) system.

Universal Mobile Telecommunications System (UMTS) is a third generation (3G) cellular telephone technology. UTRAN (abbreviation for UMTS terrestrial radio access network) is a collective term for the node bs and radio network controllers that make up the UMTS core network. The communication network can carry many traffic types, from real-time circuit switched to IP based packet switched. UTRAN allows connection between UE (user equipment) and the core network. The UTRAN includes base stations, also referred to as node bs, and Radio Network Controllers (RNCs). The RNC provides control functions for one or more node bs. The node B and RNC may be the same device, although a typical implementation has a separate RNC located at a central office that serves multiple node bs. They have a logical interface between them called Iub, although in practice they do not have to be physically separated. The RNC and its corresponding node bs are referred to as Radio Network Subsystems (RNS). There may be more than one RNS in the UTRAN.

The 3GPP LTE (long term evolution) is the name of an item in the third generation partnership project (3 GPP) that improves the UMTS mobile phone standard to cope with future demands. The objectives include: increased efficiency, reduced cost, improved service, utilization of new spectrum opportunities, and better integration with other open standards. The LTE system is described in the evolved utra (eutra) and evolved utran (eutran) series of specifications.

One goal of LTE is to reduce segmentation of Radio Link Control (RLC) SDUs when constructing Packet Data Units (PDUs). Another object is to reduce the filling, which object and another object interact with each other. Unspecified behavior in segmentation and padding can complicate and reduce the efficiency of decoding of PDUs that unpredictably include segmentation or padding of SDUs.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosure. This summary is not an extensive overview and is intended to neither identify key or critical elements nor delineate the scope of such aspects. The purpose of the summary is to present some concepts of the described features in a simplified form as a prelude to the more detailed description that is presented later.

In accordance with one or more aspects and corresponding disclosure thereof, various aspects are described in connection with a balance between two goals of minimizing segmentation of RLC SDUs while reducing padding of PDUs constructed from SUDs.

In one aspect, a method for constructing a Packet Data Unit (PDU) is provided: receiving and storing Service Data Units (SDUs); acquiring a length value and a constraint value of a PDU to be constructed; sequentially combining the stored SDUs without exceeding the length value; and, based on a comparison between the PDU remainder and the constraint value, determining to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In another aspect, at least one processor for constructing a Packet Data Unit (PDU) is provided. A first module for receiving and storing a Service Data Unit (SDU). A second module for obtaining a length value and a constraint value of the PDU to be constructed. A third module for sequentially combining the stored SDUs without exceeding the length value. A fourth module for determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In another aspect, a computer program product for constructing a Packet Data Unit (PDU) is provided. The computer-readable storage medium includes: a first code group for receiving and storing a Service Data Unit (SDU) by a computer. A second code group for causing the computer to obtain a length value and a constraint value of the PDU to be constructed. A third code group for causing the computer to sequentially combine the stored SDUs without exceeding the length value. A fourth set of codes for determining, based on a comparison between the remaining portion of the PDU and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In another aspect, an apparatus for constructing a Packet Data Unit (PDU) is provided. Means are provided for receiving and storing Service Data Units (SDUs). Means are provided for obtaining a length value of the PDU to be built and a constraint value. Means are provided for sequentially combining the stored SDUs without exceeding the length value. Means are provided for determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In a further aspect, an apparatus for constructing a Packet Data Unit (PDU) is provided. The memory receives and stores Service Data Units (SDUs). The calculation platform obtains the length value and the constraint value of the PDU to be constructed. The computing platform sequentially combines the stored SDUs without exceeding the length value. The computing platform determines, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In yet another aspect, a method for decoding a Packet Data Unit (PDU) is provided: wirelessly receiving and storing Packet Data Units (PDUs) from a transmitting entity; and, deterministically decoding segmentation and padding of Service Data Units (SDUs) by predicting operation of the transmitting entity. It is known that the sending entity constructs the PDU by: receiving and storing Service Data Units (SDUs); acquiring a length value and a constraint value of a PDU to be constructed; sequentially combining the stored SDUs without exceeding the length value; and determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In another aspect, at least one processor for decoding a Packet Data Unit (PDU) is provided. A first module wirelessly receives and stores Packet Data Units (PDUs) from a transmitting entity. A second module deterministically decodes segmentation and padding for Service Data Units (SDUs) by predicting operation of a transmitting entity. It is known that the sending entity constructs the PDU by: receiving and storing Service Data Units (SDUs); acquiring a length value and a constraint value of a PDU to be constructed; sequentially combining the stored SDUs without exceeding the length value; and determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In yet another aspect, a computer program product for decoding a Packet Data Unit (PDU) is provided. The computer-readable storage medium includes: a first code group for causing a computer to wirelessly receive and store Packet Data Units (PDUs) from a transmitting entity. A second code group for causing a computer to deterministically decode segmentation and padding of Service Data Units (SDUs) by predicting operation of a transmitting entity. It is known that the sending entity constructs the PDU by: receiving and storing Service Data Units (SDUs); acquiring a length value and a constraint value of a PDU to be constructed; sequentially combining the stored SDUs without exceeding the length value; and determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In another aspect, an apparatus for decoding a Packet Data Unit (PDU) is provided. Means are provided for wirelessly receiving and storing Packet Data Units (PDUs) from a transmitting entity. Means are provided for deterministically decoding segmentation and padding of Service Data Units (SDUs) by predicting operation of a transmitting entity. It is known that the sending entity constructs the PDU by: receiving and storing Service Data Units (SDUs); acquiring a length value and a constraint value of a PDU to be constructed; sequentially combining the stored SDUs without exceeding the length value; and determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

In yet another aspect, an apparatus for decoding a Packet Data Unit (PDU) is provided. A receiver wirelessly receives Packet Data Units (PDUs) from a transmitting entity. A memory stores the PDU. A computing platform deterministically decodes segmentation and padding for Service Data Units (SDUs) by predicting the operation of a sending entity. It is known that the sending entity constructs the PDU by: receiving and storing Service Data Units (SDUs); acquiring a length value and a constraint value of a PDU to be constructed; sequentially combining the stored SDUs without exceeding the length value; and determining, based on a comparison between the PDU remainder and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU or padding the PDU.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative aspects and are indicative of but a few of the various ways in which the principles of the aspects may be employed. Other advantages and novel features will become apparent from the following detailed description when considered in conjunction with the drawings and the disclosed aspects are intended to include all aspects and their equivalents.

Drawings

The features, nature, and advantages of the present disclosure will become more apparent from the detailed description set forth below when taken in conjunction with the drawings in which like reference characters identify correspondingly throughout and wherein:

fig. 1 shows a block diagram of a communication system in which a transmitting entity performs Radio Link Control (RLC) sublayer segmentation or padding on Service Data Units (SDUs) in a deterministic, balanced manner when constructing Packet Data Units (PDUs);

FIG. 2 illustrates a flow chart of a method or sequence of operations for deterministic segmentation, re-segmentation and padding;

FIG. 3 shows a timing diagram of a Medium Access Control (MAC) -initiated RLC-MAC interaction;

FIG. 4 illustrates a data structure of a Packet Data Convergence Protocol (PDCP) Packet Data Unit (PDU);

FIG. 5 shows a data structure for an RLC PDU structure with segmentation and padding;

fig. 6 shows a method or sequence of operation of the RLC sublayer for the downlink;

fig. 7 shows a schematic diagram of segmentation of an RLC SDU to accommodate the required length;

FIG. 8 illustrates a schematic diagram of a multiple access wireless communication system in accordance with an aspect for deterministic segmentation, re-segmentation, and padding;

FIG. 9 shows a schematic block diagram of a communication system for deterministic segmentation, re-segmentation and padding;

fig. 10 shows a block diagram of a base station and a user equipment for deterministic segmentation, re-segmentation and padding;

FIG. 11 illustrates a block diagram of a system including a logical grouping of electronic components for deterministic segmentation, re-segmentation, and population;

FIG. 12 illustrates a block diagram of a system including a logical grouping of electronic components for deterministic segmentation, re-segmentation, and population;

FIG. 13 shows a block diagram of an apparatus for constructing decoded Packet Data Units (PDUs);

fig. 14 shows a block diagram of an apparatus for decoding Packet Data Units (PDUs).

Detailed Description

Various aspects are now described with reference to the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. It may be evident, however, that the various aspects may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing these aspects.

Referring initially to fig. 1, a communication system 100 of a base station is shown, wherein the base station is depicted as an evolved node b (eNB) 102 that communicates with a User Equipment (UE) 106 via an over-the-air (OTA) link 104. In an illustrative aspect, the UE106 constructs Packet Data Units (PDUs) from Radio Link Control (RLC) sublayer Service Data Units (SDUs). In particular, the RLC SDU component 108 uses a deterministic RLC segmentation, re-segmentation and padding method or sequence of operations (block 110) that balances two objectives, namely: the goal of segmentation of the RLC SDU is reduced in the construction (block 112), and the goal of padding in the PDU is reduced (block 114). Further, the value may be expressed as a percentage or fraction of the segment length.

The eNB102 may signal on the Downlink (DL) 120 with radio resource control segments and/or padding values (block 118). These values may be specific to the RLC instance of the data radio bearer or the signalling radio bearer. Alternatively, as shown at 122, these values may be predefined, whether enforced or automatically complied with. eNB102 has an RLC SDU component 124 that is aware of the method or sequence of operations 110 so that eNB102 can deterministically predict how UE106 segments and/or fills a wirelessly transmitted PDU126 on an Uplink (UL) 128 to eNB 102. It should be appreciated, with the benefit of this disclosure, that a transmitting entity (e.g., UE 106) may consider the header overhead of all lower layers (e.g., RLC/MAC) before deciding whether segmentation of SDUs is required for a given grant.

In the illustrative scenario depicted in fig. 2, a method or sequence of operations 200 is shown that advantageously enables a transmitting Radio Link Control (RLC) entity (e.g., a User Equipment (UE)) to reduce segmentation of RLC Service Data Units (SDUs) while minimizing padding. These two goals interact with each other. Avoiding fragmentation can result in padding ranging from 1 byte to 1499 bytes (the size of an IP frame). Thus, there is an opportunity to balance these two goals to improve processing efficiency, particularly in a deterministic manner to enable a receiving RLC entity (e.g., eNB) to more easily reassemble RLC SDUs without excessive loss of over-the-air (OTA) resources due to padding. In particular, the advantage of the present improvement is that the behavior of the transmitting side on how to determine when to fill and when to segment can be clearly predicted. Thus, the transmitting side avoids unnecessary segmentation and the maximum number of padding is determined.

In a first scheme, described at 202, a configurable Radio Resource Control (RRC) parameter indicates a maximum number of bytes ("max _ padding _ allowed") that can be padded by the UE to avoid segmentation of RLC sdus and/or re-segmentation of retransmitted RLC Packet Data Units (PDUs). For example, the maximum number of bytes may be selected to be 40 bytes, 80 bytes, 160 bytes, and so on. The value may also be determined based on a specified or selected minimum segment size ("minimum _ segmentation _ size"), for example: values 40, 80, 160, etc.

In a second scheme, depicted at 204, a constant may be specified for the transmitting entity (e.g., UE) that indicates the maximum number of bytes in bytes (max _ padding _ allowed) or the minimum segment size (minimum _ segmentation _ size) that the UE can pad/segment to avoid unnecessary segments. In some instances, the configurable RRC parameter may replace the specified parameter. The constant may allow the UE to avoid unnecessary segmentation of the IP frame if the grant does not match the SDU size. Different or the same parameters may be applied to the signalling and data Radio Bearers (RBs). In an aspect, the constant may also be specified in terms of a percentage of RLC SDUs to be segmented or SDUs that have been segmented. The combination of the percentage and the max _ padding _ allowed parameter may be used to determine whether to segment an RLC SDU (or segmented RLC PDU).

In a third scheme, shown at 206, the values specified may be non-mandatory, for example, when the sending entity may choose to employ parameters to avoid segmentation in cases where the grant for RLC instances is low. In some instances, such automatic implementations may be applied to one or both sides of a communication link (e.g., network and UE). For example, the network may use the same or similar methods as the UE, which are signaled or specified to comply with these parameters.

Based on configurable RRC parameters (block 202), specified constants (block 204), or automatic implementation (block 206), it is determined in block 208 whether the available grant for the RLC instance is greater than the max _ padding _ allowed parameter. If so, the UE should refrain from segmenting RLC SDUs with segmentation payload lengths less than the max _ padding _ allowed byte (block 210). The parameter may be for all RLC entries (block 212), or may be on a per Radio Bearer (RB) basis (block 214), or the parameter may be valid only for data RBs (block 216), or the parameter may take different values for signaling and data RBs (block 218). Otherwise, at block 208, if the available grant for the RLC instance is less than the max _ padding _ allowed parameter, then in a first optional implementation shown at 220, the UE segments according to the grant without regard to the max _ padding _ allowed parameter or similar (block 222). In a second alternative implementation, shown at 224, which may be performed alternatively or in addition to the first alternative implementation 220, the UE sends only the complete SDU or last segment of the RLC SDU/PDU when the grant is less than the max _ padding _ allowed parameter (block 226). Examples of such use may be VoIP traffic, control PDUs or the last segment of a segmented RLC SDU/PDU, etc. In a third alternative implementation, shown at 228, performed in lieu of or in addition to implementations 220 and 224, the UE may be configured to not segment the RLC SDU on the data RB, but to segment the Signaling Radio Bearer (SRB), or otherwise process (block 230). By virtue of the above implementation, the network gains control over the maximum padding expected from the UE, avoiding excessive fragmentation. Furthermore, the options 220, 224, and 228 described above may help the transmission entity (UE) avoid segmenting SDUs into very small chunks of bytes while minimizing padding.

In fig. 3, a MAC-initiated RLC/MAC interworking 300 that benefits from deterministic segmentation, re-segmentation and padding is depicted as layer-2 for an illustrative implementation of E-UTRA (evolved universal mobile telecommunications system terrestrial radio access). In the PDCP (packet data convergence protocol) sublayer, there is one PDCP object per logical channel. The RLC sublayer has one RLC object for each UE on the UE and on the eNB (evolved base node) node, while the MAC (medium access control) sublayer has one MAC object for each UE on the UE node and one MAC object for all UEs on the eNB.

With respect to Radio Link Control (RLC), each RLC object can handle 16 uplink and downlink flows simultaneously. The RLC sublayer constructs each PDU using dynamic PDU sizes, depending on the size required by the lower layers. Each PDU may have multiple SDUs and support segmentation and padding of SDUs. The main services provided by the RLC sublayer for the higher layers are: (a) sequentially passing higher layer PDUs; and (b) delivery of higher layer PDUs supporting UM (unacknowledged mode). The main service provided by the RLC sublayer to the lower layers is dynamic PDU size. The main functions are: (a) detecting a copy; (b) segmentation for dynamic PDU size without padding; and (c) concatenation of SDUs for the same radio bearer.

Incoming data is processed and transferred in a linear fashion, layer by layer. The interaction between the RLC and PDCP sublayers occurs in the same manner when data is transmitted. Although the MAC sublayer 304 transmits only a predetermined number of data to the underlying PHY sublayer in each TTL (transmission time interval), the interface between the RLC302 and the MAC sublayer 304 is more complex.

Between the RLC302 and MAC sublayer 304, at the RLC sublayer 302, all RLC SDUs (service data units) 306 are queued as shown at 308, and the MAC304 determines when to construct PDUs (packet data units) from them, which are described as being triggered by the TTI timer 310. When a transmission is planned, the MAC304 requests the RLC sublayer 302 for a PDU 312. Since the RLC304 has all SDUs 306 in the queue 308, it takes as much data as possible up to the defined number specified by the MAC sublayer 304 in the request 312, and constructs a PDU314 therefrom. The MAC sublayer 304 may then decide to request more PDUs 316 after receiving each PDU314, or add padding if more space remains in the Transport Block (TB) 318. The TB is then transmitted as shown at 320.

In fig. 4, a Packet Data Convergence Protocol (PDCP) PDU330 is shown. The PDCP sublayer transfers data between the RLC sublayer and the node object. When receiving data from the node object, the PDCP header 332 is added to the PDCP payload 334 (PDCP sdu) which includes a sequence number two bytes long before passing the packet to the RLC sublayer. When data is transferred from the RLC sublayer to the PDCP sublayer, the PDCP header is deleted before the packet is transferred to the node object.

In fig. 5, an RLC PDU structure 340 is shown. The RLC header 342 includes a sequence number 344, a full/partial (CP) field 346, and an extension bit (E) 348. More header fields may follow depending on the number of SDUs in each RLC PDU 340. These extra fields may be omitted for one SDU, but one Length Indicator (LI) 350 and one E bit 352 may be added for each additional SDU. Sequence number 344 may be used for duplicate detection and sequential delivery to upper layers. The full/partial field 346 supports segmentation and concatenation by indicating with a first bit whether the start of the first SDU354 is segmented and with a second bit whether the end of the last SDU356 is segmented. The E bit 348 indicates whether more header fields follow or whether the remainder of the PDU contains SDUs. LI350 follows to indicate where the first SDU ends and where the next SDU begins, if there are more header fields. Following the LI field 350 is another E bit 352. There is one LI field 350 and one E bit 352 for each SDU356 in each RLC PDU340, except for the last SDU 358. The length of the last SDU358 can be calculated by subtracting the sum of all existing LIs 350 from the length of the RLC PDU 340. Padding 360 is added to the RLC header 342 to byte align the RLC payload 362 if needed.

In fig. 6, a process 370 for constructing and transmitting RLC PDUs is shown. Upon receiving SDUs 372 from the PDCP sublayer 374, the RLC sublayer 376 stores the SDUs 372 in the SDU-list 378 in the order received. Each channel in the RLC sublayer 374 has its own SDU-list 378 and operates independently of each other. SDUs 372 are buffered in the RLC sublayer 376 until the MAC sublayer 380 requests data from the RLC channel 376. As shown at 382, the MAC sublayer 380 requests data and informs the RLC sublayer 376 of the maximum size of channels and RLC PDUs that can be sent to the MAC sublayer 380. If the data in the buffer 378 for a given RLC channel is less than the required size, the PDU construction component 384 for the RLC channel puts all SDUs 372 belonging to the given channel in the same PDU386, adds an RLC header, and passes the RLC PDU to the MAC sublayer. If the designated RLC channel has sufficient data, PDUs of the required size are constructed and segmented if necessary.

In fig. 7, a data structure 400 is shown for segmentation of an RLC header 404 and RLC payload 406 when padding is not required to construct a dynamically sized RLC PDU 402. When the RLC sublayer receives the requested RLC PDU length from the MAC sublayer, the RLC sublayer may need to send the last segment of RLC SDU N408, be able to send the complete RLC SDUs N +1410 and N +2412, and then need to segment the last SDU414 in PDU402 to fit the requested length. Unless the last SDU fits exactly, the last SDU is to be segmented or padded appropriately to meet the requested size.

On the receiving side (e.g., eNB), when the RLC sublayer receives an RLC PDU from the MAC sublayer, a sequence check is performed to ensure sequential delivery of SDUs to the PDCP sublayer and to correctly reconstruct the segmented SDUs. If the received RLC PDU is the desired RLC PDU, processing and transmission of the RLC PDU are performed. Otherwise, duplicate detection is performed before placing the RLC PDUs in the waiting queue. The RLC PDU is transmitted from the waiting queue when all expected RLC PDUs before the RLC PDU have been received. Each RLC PDU is stored in the wait queue for a short period of time. When the RLC PDU waits for a certain time, a timeout occurs, and then it is considered that the desired RLC PDU is lost, and the waiting RLC PDU is transmitted from the queue.

It should be appreciated that wireless communication systems are widely deployed to provide various communication content such as voice, data, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, 3GPP LTE systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, and the like.

Generally, a wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. Each terminal may communicate with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. The communication link may be established via a single-input single-output system, a multiple-input multiple-output (MIMO) system.

MIMO systems using multiple (N)_TMultiple) transmitting antenna and multiple (N)_RMultiple) receive antennas for data transmission. From N_TA transmitting antenna and N_RThe MIMO channel formed by the receiving antennas can be decomposed into N_SIndividual channels, which may also be referred to as spatial channels, where N_S≤min{N_T,N_R}。N_SEach of the individual channels corresponds to a dimension. MIMO systems may provide improved performance (e.g., higher throughput and/or greater reliability) if the additional dimensionalities created by the multiple transmit and receive antennas are utilized.

MIMO systems support Time Division Duplex (TDD) and Frequency Division Duplex (FDD) systems. In a TDD system, the forward and reverse link transmissions are in the same frequency domain, so that the reciprocity principle allows the estimation of the forward link channel from the reverse link channel. This allows the access point to obtain transmit beamforming gain on the forward link when multiple antennas are available on the access point.

Referring to fig. 8, a multiple access wireless communication system in accordance with an aspect is illustrated. An access point 450 (AP) includes multiple antenna groups, one including 454 and 456, another including 458 and 460, and an additional including 462 and 464. In fig. 8, only two antennas are shown for each antenna group, however, more or fewer antennas may be utilized for each antenna group. Access Terminal (AT) 466 is in communication with antennas 462 and 464, where antennas 462 and 464 transmit information to access terminal 466 over forward link 470 and receive information from access terminal 466 over reverse link 468. Access terminal 472 is in communication with antennas 456 and 458, where antennas 456 and 458 transmit information to access terminal 472 over forward link 476 and receive information from access terminal 472 over reverse link 474. In a FDD system, communication links 468, 470, 474 and 476 may use different frequency for communication. For example, forward link 470 may use a different frequency than that used by reverse link 468. Each group of antennas and/or the area in which they are designed to communicate is often referred to as a sector of access point 450. In this scenario, antenna groups each are designed to communicate to access terminals 466 and 472 in a sector of the areas covered by access point 450.

In communication over forward links 470 and 476, the transmitting antennas of access point 450 utilize beamforming to improve the signal-to-noise ratio of forward links for the different access terminals 466 and 472. Moreover, an access point utilizing beamforming to transmit to access terminals scattered randomly through its coverage causes less interference to access terminals in neighboring cells than an access point transmitting through a single antenna to all its access terminals.

Access point 450 may be a fixed station used for communicating with the terminals and may also be referred to as an access point, a node B, or some other terminology. Access terminals 466 and 472 may also be referred to as User Equipment (UE), a wireless communication device, a terminal, an access terminal, or some other terminology.

Fig. 9 is a block diagram of an aspect of a transmitter system 510 (also referred to as an access point) and a receiver system 550 (also referred to as an access terminal) in a MIMO system 500. At the transmitter system 510, traffic data for a number of data streams is provided from a data source 512 to a Transmit (TX) data processor 514.

In one aspect, each data stream is transmitted over a respective transmit antenna. TX data processor 514 format, codes, and interleaves the traffic data for each data stream based on a particular coding scheme selected for that data stream to provide coded data.

The pilot data may be multiplexed with the coded data for each data stream using OFDM techniques. The pilot data is typically a known data pattern that is processed in a known manner and may be used at the receiver system to estimate the channel response. The multiplexed pilot and coded data for each data stream is then modulated (i.e., symbol mapped) based on a particular modulation scheme (e.g., BPSK, QPSK, M-PSK, or M-QAM) selected for that data stream to provide modulation symbols. The data rate, coding, and modulation for each data stream may be determined by instructions performed by processor 530.

The modulation symbols for all data streams are then provided to a TX MIMO processor 520, which may further process the modulation symbols (e.g., for OFDM). TX MIMO processor 520 then passes N_TOne modulation symbol stream is provided to N_TA transmitter (TMTR) 522a through 522 t. In particular implementations, TX MIMO processor 520 applies beamforming weights to the symbols of the data streams and to the antenna from which the symbol is being transmitted.

Each transmitter 522 receives and processes a respective symbol stream to provide one or more analog signals, and further conditions (e.g., amplifies, filters, and upconverts) the analog signals to provide a signal suitable for transmission over the MIMO channelThe transmitted modulated signal. Then, N from transmitters 522a through 522t_TFrom N modulated signals_TAnd antennas 524a through 524 t.

At receiver system 550, the transmitted modulated signal is divided by N_RReceived by antennas 552a through 552r and the received signal from each antenna 552 is provided to a respective receiver (RCVR) 554a through 554 r. Each receiver 554 conditions (e.g., filters, amplifies, and downconverts) a respective received signal, digitizes the conditioned signal to provide samples, and further processes the samples to provide a corresponding "received" symbol stream.

RX data processor 560 then receives data from N based on a particular receiver processing technique_RN of one receiver 554_RA stream of received symbols and processing them to provide N_TA "detected" symbol stream. RX data processor 560 then demodulates, deinterleaves, and decodes each detected symbol stream to recover the traffic data for the data stream. The processing by RX data processor 560 is complementary to that performed by TX MIMO processor 520 and TX data processor 514 at transmitter system 510.

A processor 570 periodically determines which pre-coding matrix to use (discussed below). Processor 570 formulates a reverse link message comprising a matrix index portion and a rank value portion.

The reverse link message may comprise various types of information regarding the communication link and/or the received data stream. The reverse link message is then processed by a TX data processor 538, modulated by a modulator 580, conditioned by transmitters 554a through 554r, and transmitted back to transmitter system 510, where TX data processor 538 also receives traffic data for a number of data streams from a data source 536.

At transmitter system 510, the modulated signals from receiver system 550 are received by antennas 524, conditioned by receivers 522, demodulated by a demodulator 540, and processed by a RX data processor 542 to obtain the reverse link message transmitted by receiver system 550. Processor 530 then determines the precoding matrix to use for determining the beamforming weights and then processes the received message.

In one aspect, logical channels are classified into control channels and traffic channels. Logical control channels include a Broadcast Control Channel (BCCH), which is a DL channel for broadcasting system control information. Paging Control Channel (PCCH), which is DL channel for transferring paging information. A Multicast Control Channel (MCCH) which is a point-to-multipoint DL channel used for transmitting control information for multimedia broadcast, multicast service (MBMS) scheduling and one or more MTCHs. Typically, this channel is only used by UEs receiving MBMS (note: old MCCH + MSCH) after RRC connection is established. Dedicated Control Channel (DCCH) is a point-to-point bi-directional channel used to transmit dedicated control information and used by UEs having an RRC connection. In one aspect, the logical traffic channels include a Dedicated Traffic Channel (DTCH), which is a point-to-point bi-directional channel dedicated to one UE to communicate user information. Also, a Multicast Traffic Channel (MTCH) is a point-to-multipoint DL channel for transmitting traffic data.

In one aspect, transport channels are classified as DL and UL. DL transport channels include a Broadcast Channel (BCH), downlink shared data channel (DL-SDCH) and a Paging Channel (PCH), the PCH for support of UE power saving (DRX cycle period is indicated by the network to the UE), broadcasted over the entire cell and mapped to PHY resources that can be used for other control/traffic channels. The UL transport channels include a Random Access Channel (RACH), a request channel (REQCH), an uplink shared data channel (UL-SDCH), and a plurality of PHY channels. The PHY channels include a set of DL channels and UL channels.

The DL PHY channels include: common pilot channel (CPICH); a Synchronization Channel (SCH); common Control Channel (CCCH); shared DL Control Channel (SDCCH); multicast Control Channel (MCCH); shared UL Allocation Channel (SUACH); acknowledgement channel (ACKCH); DL physical shared data channel (DL-PSDCH); UL Power Control Channel (UPCCH); a Paging Indicator Channel (PICH); load Indicator Channel (LICH); the UL PHY channels include: physical Random Access Channel (PRACH); a Channel Quality Indicator Channel (CQICH); acknowledgement channel (ACKCH); an Antenna Subset Indicator Channel (ASICH); shared request channel (SREQCH); UL physical shared data channel (UL-PSDCH); a wideband pilot channel (BPICH).

The following abbreviations are used in this document:

in fig. 10, a serving Radio Access Network (RAN), depicted as an evolved base station node (eNB) 600, has a computing platform 602, the computing platform 602 providing a plurality of modules (e.g., sets of codes) for a computer to decode Packet Data Units (PDUs). In particular, computing platform 602 includes a computer-readable storage medium (e.g., memory) 604 that stores a plurality of modules 606 and 608 that are executed by processor 602. A modulator 622, controlled by a processor 620, prepares a downlink signal for modulation by a transmitter 624, which is transmitted by an antenna 626. A receiver 626 receives the uplink signal from the antenna 626, which is demodulated by a demodulator 630 and provided to a processor 620 for decoding. In particular, means (e.g., a module or set of codes) 606 for wirelessly receiving and storing Packet Data Units (PDUs) from a transmitting entity is provided. An apparatus (e.g., module, set of codes) 608 is provided for deterministically decoding segmentation and padding of Service Data Units (SDUs) by predicting operation of a transmitting entity. The model 610 provides knowledge of how the sending entity constructs the PDU.

With continued reference to fig. 10, a mobile station depicted as User Equipment (UE) 650 has a computing platform 652 that provides a plurality of means (e.g., a set of codes) for causing a computer to construct PDUs. In particular, computing platform 652 includes a computer-readable storage medium (e.g., memory) 654 that stores a plurality of modules 656 and 662 that are executed by processor 670. A modulator 672, controlled by a processor 670, prepares the uplink signal for modulation by a transmitter 674 for transmission by an antenna 676 to eNB600 (shown as 677). Receiver 678 receives the downlink signal from eNB600 from antenna 676, which is demodulated by a demodulator 680 and provided to a processor 670 for decoding. In particular, an apparatus (e.g., module, set of codes) 656 for receiving and storing Service Data Units (SDUs) is provided. Means (e.g., a module, a set of codes) 658 are provided for obtaining a length value and a constraint value for the PDU to be built. Means (e.g., module, code set) 660 are provided for sequentially combining stored SDUs without exceeding a length value. Means (e.g., a module, a set of codes) 662 for determining, based on a comparison between a remaining portion of the PDU and the constraint value, to perform one of: segmenting the last SDU or padding the PDU.

Referring to fig. 11, illustrated is a system 700 that effectuates building a PDU. For example, system 700 can reside at least partially within a User Equipment (UE). It is to be appreciated that system 700 is represented as including functional blocks, which can be functional blocks that represent functions implemented by a processor, software, or combination thereof (e.g., firmware). System 700 includes a logical grouping 702 of electrical components that can act in conjunction. For instance, logical grouping 702 can include an electrical component for receiving and storing a Service Data Unit (SDU) 704. Further, logical grouping 702 can include an electrical component for obtaining a length value and a constraint value for the PDU to be built 706. Additionally, logical grouping 702 can include an electrical component for sequentially combining stored SDUs without exceeding a length value 708. Further, logical grouping 702 can comprise an electrical component for determining, based on comparing the remaining portion of the PDU to the constraint value, to perform one of the following operations to reach the length value, the operations comprising: segmenting the last SDU or padding the PDU. Additionally, system 700 can include a memory 712 that can retain instructions for performing functions associated with electrical components 704 and 706. While electronic components 704, 706, and 708 are shown as being external to memory 712, it is to be understood that one or more of electronic components 704, 706, and 708 can exist within memory 712.

Referring to FIG. 12, a system 800 is shown that enables allocation and enables the use of measurement gaps. For example, system 800 can reside at least partially within a base station. It is to be appreciated that system 800 is represented as including functional blocks, which can represent functions implemented by a processor, software, or combination thereof (e.g., firmware). System 800 includes a logical grouping 802 of electrical components that can act in conjunction. For instance, logical grouping 802 can include an electrical component for wirelessly receiving and storing Packet Data Units (PDUs) 804 from a transmitting entity. Moreover, logical grouping 802 can include an electrical component for deterministically decoding segmentation and padding of Service Data Units (SDUs) by predicting operation of a transmitting entity 806. Additionally, logical grouping 802 can include an electrical component for containing a model that provides knowledge of how the transmitting entity constructed the PDU 808. Additionally, system 800 can include a memory 812 that retains instructions for executing functions associated with electrical components 804, 806, and 808. While shown as being external to memory 812, it is to be understood that one or more of electrical components 804, 806, and 808 can exist within memory 812.

In fig. 13, an apparatus 902 for constructing a Packet Data Unit (PDU) is shown. A module 904 for receiving and storing Service Data Units (SDUs) is provided. A module 906 for obtaining a length value of the PDU to be built and a constraint value is provided. A module 908 is provided for sequentially combining the stored SDUs without exceeding the length value. A module 910 is provided for determining, based on a comparison between a remaining portion of the PDU and the constraint value, to perform one of the following operations to reach the length value: segmenting the last SDU and padding the PDU.

In fig. 14, an apparatus 1002 for decoding a Packet Data Unit (PDU) is shown. A module 1004 is provided for wirelessly receiving and storing Packet Data Units (PDUs) from a transmitting entity. A module 1006 for deterministically decoding segmentation and padding of Service Data Units (SDUs) by predicting operation of a transmitting entity is provided. A module 1008 is provided for providing knowledge of how a sending entity constructs a PDU, known to construct a PDU by: receiving and storing a Service Data Unit (SDU), obtaining a length value and a constraint value of a PDU to be constructed, sequentially combining the stored SDUs without exceeding the length value, and determining, based on a comparison between a remaining portion of the PDU and the constraint value, to perform one of the following operations to reach the length value, the operations being: segmenting the last SDU or padding the PDU.

The above description includes examples of various aspects. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the various aspects, but one of ordinary skill in the art may recognize that many further combinations and permutations are possible. Accordingly, the subject specification is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims.

In particular regard to the various functions performed by the above described components, devices, circuits, systems and the like, the terms (including a reference to a "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure, which performs the function in the herein illustrated exemplary implementations. In this regard, it will be understood that the various aspects include a system and also include a computer-readable medium having computer-executable instructions for performing the acts and/or events of the various methods.

In addition, while a particular feature may have been disclosed with respect to only one of several implementations, one or more other features of the other implementations may be combined with the feature as may be desired and advantageous for any given or particular application. With respect to the use of the words "include" and "have" and variations thereof in the detailed description and claims, these words are intended to be inclusive in a manner similar to the word "comprising". Furthermore, the word "or" as used in the detailed description and claims means "a non-exclusive or".

Further, it should be understood that portions of the disclosed systems and methods may include or have: artificial intelligence, machine learning, or knowledge/rule-based components, subcomponents, processes, modules, methods, or mechanisms (e.g., support vector machines, neural networks, expert systems, Bayesian belief networks, fuzzy logic, data fusion engines, classifiers, etc.). These components, and others, may be automated in the mechanisms or processes performed, thus making the systems and methods more adaptable, efficient, and intelligent. By way of example and not limitation, an evolved RAN (e.g., access point, node B) may infer or predict a time at which to complete a robustness or enhancement check field.

As used in this application, the terms "component," "module," "system," and the like are intended to refer to a computer-related entity, either hardware, a combination of hardware and software, or software in execution. For example, a component may be, but is not limited to: a process running on a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a server and the server can be a component. One or more components may reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers.

The word "exemplary" is used herein to mean serving as an example, instance, or illustration. Any aspect described herein as "exemplary" is not to be construed as preferred or advantageous over other embodiments.

Furthermore, one or more aspects may be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques to provide software, firmware, hardware, or any combination thereof to control a computer to implement the disclosed aspects. The term "article of manufacture" (or "computer program product") as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disk, floppy disk, magnetic strips, etc.), optical disks (e.g., Compact Disk (CD), Digital Versatile Disk (DVD), etc.), smart cards, and flash memory devices (e.g., card, stick). Further, it should be appreciated that a carrier wave can be employed to carry computer-readable electronic data such as: electronic data used in sending and receiving electronic mail, or electronic data used when accessing a network (e.g., the internet, a Local Area Network (LAN)). Of course, those skilled in the art will recognize many modifications may be made to this configuration without departing from the scope of the disclosed aspects.

Various aspects will be presented in terms of systems that may include a number of components, modules, and the like. It is to be understood and appreciated that the various systems may include additional components, modules, etc. and/or may not include all of the components, modules etc. discussed in connection with the figures. A combination of these approaches may be used. Aspects disclosed herein may be implemented on an electronic device, including devices that utilize touch screen display technology and/or mouse-keyboard type interfaces. Examples of such devices include: computers (desktop or mobile), smart phones, Personal Digital Assistants (PDAs), and other wired, wireless electronic devices.

In accordance with the exemplary systems described supra, methodologies that may be implemented in accordance with the disclosed subject matter have been described with reference to a number of flowcharts. While, for purposes of simplicity of explanation, the methodologies are shown and described as a series of blocks, it is to be understood and appreciated that the claimed subject matter is not limited by the order of the blocks, as some blocks may occur in different orders and/or concurrently with other blocks from what is depicted and described herein. Moreover, not all illustrated blocks may be required to implement the methodologies described herein. Moreover, it should be further appreciated that the methodologies described herein may be stored on an article of manufacture to facilitate transporting and transferring such methodologies to computers. The word "article of manufacture" as used herein is intended to encompass a computer program accessible from any computer-readable device, carrier, or media.

It should be understood that any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that it does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. Thus, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. For any material, or portion of any material, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein, only those portions of the incorporated material that do not conflict with existing disclosure material are incorporated herein.

Claims (24)

1. A method for constructing a Packet Data Unit (PDU), comprising:

receiving and storing Service Data Units (SDUs);

acquiring a length value and a constraint value of a PDU to be constructed;

storing the SDU without exceeding the length value; and

determining whether to perform segmentation on a last SDU based on a comparison between a remaining portion of the PDU and the constraint value.

2. The method of claim 1, wherein the constraint value indicates a minimum segment size allowed.

3. The method of claim 1, wherein determining whether to perform segmentation comprises: refraining from segmenting the last SDU when the last SDU fits in the remaining portion of the PDU.

4. The method of claim 1, further comprising: available grants for a Radio Link Control (RLC) instance are compared to the constraint value.

5. The method of claim 4, further comprising: all SDUs belonging to the same RLC instance are sent in the same PDU without exceeding the length value.

6. The method of claim 1, wherein determining whether to perform segmentation comprises: fragmentation is avoided when the payload length of the fragment is less than the maximum padding allowed.

7. A computer program product for constructing Packet Data Units (PDUs), the computer program product comprising a non-transitory computer-readable medium having code stored thereon, the code executable by one or more processors for:

receiving and storing Service Data Units (SDUs);

acquiring a length value and a constraint value of a PDU to be constructed;

storing the SDU without exceeding the length value; and

determining whether to perform segmentation on a last SDU based on a comparison between a remaining portion of the PDU and the constraint value.

8. The computer program product of claim 7, wherein the constraint value indicates a minimum segment size allowed.

9. The computer program product of claim 7, wherein the code for determining whether to perform segmentation comprises: code for avoiding segmentation of the last SDU when the last SDU fits in the remaining portion of the PDU.

10. The computer program product of claim 7, further comprising: code for comparing an available grant of a Radio Link Control (RLC) instance to the constraint value.

11. The computer program product of claim 10, further comprising: code for transmitting all SDUs belonging to the same RLC instance in the same PDU without exceeding the length value.

12. The computer program product of claim 7, wherein the code for determining whether to perform segmentation comprises: code for avoiding fragmentation when the payload length of the fragmentation is less than the maximum padding allowed.

13. An apparatus for constructing Packet Data Units (PDUs), comprising:

means for receiving and storing a Service Data Unit (SDU);

a module for obtaining the length value and the constraint value of the PDU to be constructed;

means for storing the SDU without exceeding the length value; and

means for determining whether to perform segmentation for a last SDU based on a comparison between a remaining portion of the PDU and the constraint value.

14. The apparatus of claim 13, wherein the constraint value indicates a minimum segment size allowed.

15. The apparatus of claim 13, wherein the means for determining whether to perform segmentation comprises: means for avoiding segmentation of the last SDU when the last SDU fits in the remaining portion of the PDU.

16. The apparatus of claim 13, further comprising: means for comparing an available grant for a Radio Link Control (RLC) instance to the constraint value.

17. The apparatus of claim 16, further comprising: means for transmitting all SDUs belonging to the same RLC instance in the same PDU without exceeding the length value.

18. The apparatus of claim 13, wherein the means for determining whether to perform segmentation comprises: means for avoiding fragmentation when a payload length of the fragmentation is less than a maximum padding allowed.

19. An apparatus for constructing Packet Data Units (PDUs), comprising:

a memory for receiving and storing Service Data Units (SDUs); and

a computing platform for obtaining a length value and a constraint value of a PDU to be constructed, storing the SDU without exceeding the length value, and determining whether to perform segmentation on the last SDU based on a comparison between a remaining portion of the PDU and the constraint value.

20. The apparatus of claim 19, wherein the constraint value indicates a minimum segment size allowed.

21. The apparatus of claim 19, wherein determining whether to perform segmentation comprises: refraining from segmenting the last SDU when the last SDU fits in the remaining portion of the PDU.

22. The apparatus of claim 19, wherein the computing platform is further to: available grants for a Radio Link Control (RLC) instance are compared to the constraint value.

23. The apparatus of claim 22, wherein the computing platform is further to: all SDUs belonging to the same RLC instance are sent in the same PDU without exceeding the length value.

24. The apparatus of claim 19, wherein determining whether to perform segmentation comprises: fragmentation is avoided when the payload length of the fragment is less than the maximum padding allowed.