WCDMA物理层协议TS25211-910

3GPP TS 25.211 V9.1.0 (2009-12)

Technical Specification

3rd Generation Partnership Project;

Technical Specification Group Radio Access Network;

Physical channels and mapping of transport channels

onto physical channels (FDD)

(Release 9)

The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP. The present document has not been subject to any approval process by the 3GPP Organisational Partners and shall not be implemented.

This Specification is provided for future development work within 3GPP only. The Organisational Partners accept no liability for any use of this Specification. Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organisational Partners' Publications Offices.

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Keywords

UMTS, radio, layer 1

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Contents Foreword (5)

1Scope (6)

2References (6)

3Symbols, abbreviations and definitions (7)

3.1Symbols (7)

3.2Abbreviations (7)

3.3Definitions (8)

4Services offered to higher layers (8)

4.1Transport channels (8)

4.1.1Dedicated transport channels (8)

4.1.1.1DCH - Dedicated Channel (8)

4.1.1.2E-DCH – Enhanced Dedicated Channel (8)

4.1.2Common transport channels (8)

4.1.2.1BCH - Broadcast Channel (8)

4.1.2.2FACH - Forward Access Channel (8)

4.1.2.3PCH - Paging Channel (9)

4.1.2.4RACH - Random Access Channel (9)

4.1.2.5Void (9)

4.1.2.6Void (9)

4.1.2.7HS-DSCH – High Speed Downlink Shared Channel (9)

4.1.2.7A E-DCH - Enhanced Dedicated Channel (9)

4.2Indicators (9)

5Physical channels and physical signals (9)

5.1Physical signals (10)

5.2Uplink physical channels (10)

5.2.1Dedicated uplink physical channels (10)

5.2.1.1DPCCH and DPDCH (10)

5.2.1.2HS-DPCCH (13)

5.2.1.3E-DPCCH and E-DPDCH (13)

5.2.2Common uplink physical channels (15)

5.2.2.1Physical Random Access Channel (PRACH) (15)

5.2.2.1.1Overall structure of random-access transmission (15)

5.2.2.1.2RACH preamble part (16)

5.2.2.1.3RACH message part (16)

5.2.2.2Void (17)

5.3Downlink physical channels (17)

5.3.1Downlink transmit diversity (17)

5.3.1.1Open loop transmit diversity (19)

5.3.1.1.1Space time block coding based transmit antenna diversity (STTD) (19)

5.3.1.1.2Time Switched Transmit Diversity for SCH (TSTD) (21)

5.3.1.2Closed loop transmit diversity (21)

5.3.2Dedicated downlink physical channels (21)

5.3.2.1STTD for DPCH and F-DPCH (25)

5.3.2.2Dedicated channel pilots with closed loop mode transmit diversity (26)

5.3.2.3Void (27)

5.3.2.4E-DCH Relative Grant Channel (27)

5.3.2.5E-DCH Hybrid ARQ Indicator Channel (29)

5.3.2.6Fractional Dedicated Physical Channel (F-DPCH) (29)

5.3.3Common downlink physical channels (30)

5.3.3.1Common Pilot Channel (CPICH) (30)

5.3.3.1.1Primary Common Pilot Channel (P-CPICH) (31)

5.3.3.1.2Secondary Common Pilot Channel (S-CPICH) (31)

5.3.3.2Downlink phase reference (32)

5.3.3.3Primary Common Control Physical Channel (P-CCPCH) (33)

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5.3.3.3.1Primary CCPCH structure with STTD encoding (34)

5.3.3.4Secondary Common Control Physical Channel (S-CCPCH) (34)

5.3.3.4.1Secondary CCPCH structure with STTD encoding (37)

5.3.3.5Synchronisation Channel (SCH) (37)

5.3.3.5.1SCH transmitted by TSTD (38)

5.3.3.6Void (38)

5.3.3.7Acquisition Indicator Channel (AICH) (38)

5.3.3.8Void (42)

5.3.3.9Void (42)

5.3.3.10Paging Indicator Channel (PICH) (42)

5.3.3.11Void (43)

5.3.3.12Shared Control Channel (HS-SCCH) (43)

5.3.3.13High Speed Physical Downlink Shared Channel (HS-PDSCH) (43)

5.3.3.14E–DCH Absolute Grant Channel (E-AGCH) (44)

5.3.3.15MBMS Indicator Channel (MICH) (44)

6Mapping and association of physical channels (45)

6.1Mapping of transport channels onto physical channels (45)

6.2Association of physical channels and physical signals (46)

7Timing relationship between physical channels (47)

7.1General (47)

7.2PICH/S-CCPCH timing relation (48)

7.2A PICH/HS-SCCH timing relation (48)

7.3PRACH/AICH timing relation (49)

7.3A UL/DL timing relation for Enhanced Uplink in CELL_FACH state and IDLE mode (50)

7.4Void (51)

7.5Void (51)

7.6DPCCH/DPDCH timing relations (51)

7.6.1Uplink (51)

7.6.2Downlink (51)

7.6.3Uplink/downlink timing at UE (51)

7.7Uplink DPCCH/HS-DPCCH/HS-PDSCH timing at the UE (51)

7.8HS-SCCH/HS-PDSCH timing (52)

7.9MICH/S-CCPCH timing relation (52)

7.10E-HICH/P-CCPCH/DPCH timing relation (53)

7.11E-RGCH/P-CCPCH/DPCH timing relation (53)

7.12E-AGCH/P-CCPCH timing relation (54)

7.13E-DPDCH/E-DPCCH/DPCCH timing relation (54)

Annex A (informative): Change history (55)

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3GPP TS 25.211 V9.1.0 (2009-12) Foreword

This Technical Specification (TS) has been produced by the 3rd Generation Partnership Project (3GPP).

The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows:

Version x.y.z

where:

x the first digit:

1 presented to TSG for information;

2 presented to TSG for approval;

3 or greater indicates TSG approved document under change control.

y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc.

z the third digit is incremented when editorial only changes have been incorporated in the document.

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3GPP TS 25.211 V9.1.0 (2009-12) 1 Scope

The present document describes the characteristics of the Layer 1 transport channels and physicals channels in the FDD mode of UTRA. The main objectives of the document are to be a part of the full description of the UTRA Layer 1, and to serve as a basis for the drafting of the actual technical specification (TS).

2 References

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

?References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.

?For a specific reference, subsequent revisions do not apply.

?For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.

[1] 3GPP TS 25.201: "Physical layer - general description".

[2] 3GPP TS 25.211: "Physical channels and mapping of transport channels onto physical channels

(FDD)".

[3] 3GPP TS 25.212: "Multiplexing and channel coding (FDD)".

[4] 3GPP TS 25.213: "Spreading and modulation (FDD)".

[5] 3GPP TS 25.214: "Physical layer procedures (FDD)".

[6] 3GPP TS 25.221: "Transport channels and physical channels (TDD)".

[7] 3GPP TS 25.222: "Multiplexing and channel coding (TDD)".

[8] 3GPP TS 25.223: "Spreading and modulation (TDD)".

[9] 3GPP TS 25.224: "Physical layer procedures (TDD)".

[10] 3GPP TS 25.215: "Physical layer - Measurements (FDD)".

[11] 3GPP TS 25.301: "Radio Interface Protocol Architecture".

[12] 3GPP TS 25.302: "Services Provided by the Physical Layer".

[13] 3GPP TS 25.401: "UTRAN Overall Description".

[14] 3GPP TS 25.133: "Requirements for Support of Radio Resource Management (FDD)".

[15] 3G TS 25.427: "UTRAN Overall Description :UTRA Iub/Iur Interface User Plane Protocol for

DCH data streams".

[16] 3GPP TS 25.435: "UTRAN Iub Interface User Plane Protocols for Common Transport Channel

Data Streams".

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3 Symbols, abbreviations and definitions

3.1 Symbols

N data1The number of data bits per downlink slot in Data1 field.

N data2The number of data bits per downlink slot in Data2 field. If the slot format does not contain a Data2 field, N data2 = 0.

3.2 Abbreviations

For the purposes of the present document, the following abbreviations apply:

16QAM 16 Quadrature Amplitude Modulation

4PAM 4 Pulse-Amplitude Modulation

64QAM 64 Quadrature Amplitude Modulation

AI Acquisition Indicator

AICH Acquisition Indicator Channel

BCH Broadcast Channel

CCPCH Common Control Physical Channel

CCTrCH Coded Composite Transport Channel

CPICH Common Pilot Channel

CQI Channel Quality Indicator

DCH Dedicated Channel

DPCCH Dedicated Physical Control Channel

DPCH Dedicated Physical Channel

DPDCH Dedicated Physical Data Channel

DTX Discontinuous Transmission

E-AGCH E-DCH Absolute Grant Channel

E-DCH Enhanced Dedicated Channel

E-DPCCH E-DCH Dedicated Physical Control Channel

E-DPDCH E-DCH Dedicated Physical Data Channel

E-HICH E-DCH Hybrid ARQ Indicator Channel

E-RGCH E-DCH Relative Grant Channel

FACH Forward Access Channel

FBI Feedback Information

F-DPCH Fractional Dedicated Physical Channel

FSW Frame Synchronization Word

HS-DPCCH Dedicated Physical Control Channel (uplink) for HS-DSCH

HS-DSCH High Speed Downlink Shared Channel

HS-PDSCH High Speed Physical Downlink Shared Channel

HS-SCCH Shared Control Channel for HS-DSCH

ICH Indicator Channel

MBSFN MBMS over a Single Frequency Network

MICH MBMS Indicator Channel

MIMO Multiple Input Multiple Output

MUI Mobile User Identifier

NI MBMS Notification Indicator

PCH Paging Channel

P-CCPCH Primary Common Control Physical Channel

PICH Page Indicator Channel

PRACH Physical Random Access Channel

PSC Primary Synchronisation Code

RACH Random Access Channel

RNC Radio Network Controller

S-CCPCH Secondary Common Control Physical Channel

SCH Synchronisation Channel

SF Spreading Factor

SFN System Frame Number

SSC Secondary Synchronisation Code

STTD Space Time Transmit Diversity

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TFCI Transport Format Combination Indicator

TSTD Time Switched Transmit Diversity

TPC Transmit Power Control

UE User Equipment

UTRAN UMTS Terrestrial Radio Access Network

3.3 Definitions

HS-DSCH cell set: A set of cells that can be configured together as the serving and secondary serving HS-DSCH cells for a UE. This term is applicable also to non-serving cells in an active set.

4 Services offered to higher layers

4.1 Transport channels

Transport channels are services offered by Layer 1 to the higher layers. General concepts about transport channels are described in [12].

A transport channel is defined by how and with what characteristics data is transferred over the air interface. A general classification of transport channels is into two groups:

- Dedicated channels, using inherent addressing of UE;

- Common channels, using explicit addressing of UE if addressing is needed.

4.1.1 Dedicated transport channels

There exists two types of dedicated transport channel, the Dedicated Channel (DCH) and the Enhanced Dedicated Channel (E-DCH).

4.1.1.1 DCH - Dedicated Channel

The Dedicated Channel (DCH) is a downlink or uplink transport channel. The DCH is transmitted over the entire cell or over only a part of the cell using e.g. beam-forming antennas.

4.1.1.2 E-DCH – Enhanced Dedicated Channel

The Enhanced Dedicated Channel (E-DCH) is an uplink transport channel in CELL DCH.

4.1.2 Common transport channels

There are six types of common transport channels: BCH, FACH, PCH, RACH, HS-DSCH and E-DCH.

4.1.2.1 BCH - Broadcast Channel

The Broadcast Channel (BCH) is a downlink transport channel that is used to broadcast system- and cell-specific information. The BCH is always transmitted over the entire cell and has a single transport format.

4.1.2.2 FACH - Forward Access Channel

The Forward Access Channel (FACH) is a downlink transport channel. The FACH is transmitted over the entire cell. The FACH can be transmitted using power setting described in [16].

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3GPP TS 25.211 V9.1.0 (2009-12) 4.1.2.3 PCH - Paging Channel

The Paging Channel (PCH) is a downlink transport channel. The PCH is always transmitted over the entire cell. The transmission of the PCH is associated with the transmission of physical-layer generated Paging Indicators, to support efficient sleep-mode procedures.

4.1.2.4 RACH - Random Access Channel

The Random Access Channel (RACH) is an uplink transport channel. The RACH is always received from the entire cell. The RACH is characterized by a collision risk and by being transmitted using open loop power control.

4.1.2.5 Void

4.1.2.6 Void

4.1.2.7 HS-DSCH – High Speed Downlink Shared Channel

The High Speed Downlink Shared Channel is a downlink transport channel shared by several UEs. The HS-DSCH can be associated with one downlink DPCH or F-DPCH, and one or several Shared Control Channels (HS-SCCH). The HS-DSCH is transmitted over the entire cell or over only part of the cell using e.g. beam-forming antennas.

4.1.2.7A E-DCH - Enhanced Dedicated Channel

The Enhanced Dedicated Channel (E-DCH) is an uplink transport channel in CELL_FACH state and IDLE mode. 4.2 Indicators

Indicators are means of fast low-level signalling entities which are transmitted without using information blocks sent over transport channels. The meaning of indicators is specific to the type of indicator.

The indicators defined in the current version of the specifications are: Acquisition Indicator (AI), Page Indicator (PI) and MBMS Notification Indicator (NI).

Indicators may be either boolean (two-valued) or three-valued. Their mapping to indicator channels is channel specific. Indicators are transmitted on those physical channels that are indicator channels (ICH).

5 Physical channels and physical signals

Physical channels are defined by a specific carrier frequency, scrambling code, channelization code (optional), time start & stop (giving a duration) and, on the uplink, relative phase (0 or /2). The downlink E-HICH and E-RGCH are each further defined by a specific orthogonal signature sequence. Scrambling and channelization codes are specified in [4]. Time durations are defined by start and stop instants, measured in integer multiples of chips. Suitable multiples of chips also used in specification are:

Radio frame: A radio frame is a processing duration which consists of 15 slots. The length of a radio

frame corresponds to 38400 chips.

Slot: A slot is a duration which consists of fields containing bits. The length of a slot corresponds to 2560 chips.

Sub-frame: A sub-frame is the basic time interval for E-DCH and HS-DSCH transmission and E-DCH and HS-DSCH-related signalling at the physical layer. The length of a sub-frame

corresponds to 3 slots (7680 chips).

The default time duration for a physical channel is continuous from the instant when it is started to the instant when it is stopped. Physical channels that are not continuous will be explicitly described.

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Transport channels are described (in more abstract higher layer models of the physical layer) as being capable of being mapped to physical channels. Within the physical layer itself the exact mapping is from a composite coded transport channel (CCTrCH) to the data part of a physical channel. In addition to data parts there also exist channel control parts and physical signals.

5.1 Physical signals

Physical signals are entities with the same basic on-air attributes as physical channels but do not have transport channels or indicators mapped to them. Physical signals may be associated with physical channels in order to support the function of physical channels.

5.2 Uplink physical channels

5.2.1 Dedicated uplink physical channels

There are five types of uplink dedicated physical channels, the uplink Dedicated Physical Data Channel (uplink DPDCH), the uplink Dedicated Physical Control Channel (uplink DPCCH), the uplink E-DCH Dedicated Physical Data Channel (uplink E-DPDCH), the uplink E-DCH Dedicated Physical Control Channel (uplink E-DPCCH) and the uplink Dedicated Control Channel associated with HS-DSCH transmission (uplink HS-DPCCH).

The DPDCH, the DPCCH, the E-DPDCH, the E-DPCCH and the HS-DPCCH are I/Q code multiplexed (see [4]).

5.2.1.1 DPCCH and DPDCH

The uplink DPDCH is used to carry the DCH transport channel. There may be zero, one, or several uplink DPDCHs on each radio link.

The uplink DPCCH is used to carry control information generated at Layer 1. The Layer 1 control information consists of known pilot bits to support channel estimation for coherent detection, transmit power-control (TPC) commands, feedback information (FBI), and an optional transport-format combination indicator (TFCI). The transport-format combination indicator informs the receiver about the instantaneous transport format combination of the transport channels mapped to the simultaneously transmitted uplink DPDCH radio frame. There is one and only one uplink DPCCH on each radio link.

Figure 1 shows the frame structure of the uplink DPDCH and the uplink DPCCH. Each radio frame of length 10 ms is split into 5 subframes, each of 3 slots, each of length T slot = 2560 chips, corresponding to one power-control period. The DPDCH and DPCCH are always frame aligned with each other.

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Data

N d ata bits

1 radio frame: T f = 10 ms

DPDCH

DPCCH s lot data k

1 subframe =

2 ms

Figure 1: Frame structure for uplink DPDCH/DPCCH

The parameter k in figure 1 determines the number of bits per uplink DPDCH slot. It is related to the spreading factor

SF of the DPDCH as SF = 256/2k . The DPDCH spreading factor may range from 256 down to 4. The spreading factor of the uplink DPCCH is always equal to 256, i.e. there are 10 bits per uplink DPCCH slot.

The exact number of bits of the uplink DPDCH and the different uplink DPCCH fields (N pilot , N TFCI , N FBI , and N TPC ) is given by table 1 and table 2. What slot format to use is configured by higher layers and can also be reconfigured by higher layers.

The channel bit and symbol rates given in table 1 and table 2 are the rates immediately before spreading. The pilot patterns are given in table 3 and table 4, the TPC bit pattern is given in table 5.

The FBI bits are used to support techniques requiring feedback from the UE to the UTRAN Access Point for operation of closed loop mode transmit diversity. The use of the FBI bits is described in detail in [5].

Table 1: DPDCH fields

There are two types of uplink dedicated physical channels; those that include TFCI (e.g. for several simultaneous services) and those that do not include TFCI (e.g. for fixed-rate services). These types are reflected by the duplicated rows of table 2. It is the UTRAN that determines if a TFCI should be transmitted and it is mandatory for all UEs to support the use of TFCI in the uplink. The mapping of TFCI bits onto slots is described in [3].

In compressed mode, DPCCH slot formats with TFCI fields are changed. There are two possible compressed slot formats for each normal slot format. They are labelled A and B and the selection between them is dependent on the number of slots that are transmitted in each frame in compressed mode.

If UL_DTX_Active is TRUE (see [5]), the number of transmitted slots per radio frame may be less than the number shown in Table 2.

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Table 2: DPCCH fields

The pilot bit patterns are described in table 3 and table 4. The shadowed column part of pilot bit pattern is defined as FSW and FSWs can be used to confirm frame synchronization. (The value of the pilot bit pattern other than FSWs shall be "1".)

Table 3: Pilot bit patterns for uplink DPCCH with N pilot = 3, 4, 5 and 6

Table 4: Pilot bit patterns for uplink DPCCH with N pilot = 7 and 8

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Multi-code operation is possible for the uplink dedicated physical channels. When multi-code transmission is used, several parallel DPDCH are transmitted using different channelization codes, see [4]. However, there is only one DPCCH per radio link.

A period of uplink DPCCH transmission prior to the start of the uplink DPDCH transmission (uplink DPCCH power control preamble) shall be used for initialisation of a DCH. The length of the power control preamble is a higher layer parameter, N pcp , signalled by the network [5]. The UL DPCCH shall take the same slot format in the power control preamble as afterwards, as given in table 2. When N pcp > 0 the pilot patterns of table 3 and table 4 shall be used. The timing of the power control preamble is described in [5], subclause 4.3.2.3. The TFCI field is filled with "0" bits.

5.2.1.2 HS-DPCCH

Figure 2A illustrates the frame structure of the HS-DPCCH. The HS-DPCCH carries uplink feedback signalling related to downlink HS-DSCH transmission and to HS-SCCH orders according to subclause 6A.1.1 in [5]. The feedback signalling consists of Hybrid-ARQ Acknowledgement (HARQ-ACK) and Channel-Quality Indication (CQI) and in case the UE is configured in MIMO mode of Precoding Control Indication (PCI) as well [3]. Each sub frame of length 2 ms (3*2560 chips) consists of 3 slots, each of length 2560 chips. The HARQ-ACK is carried in the first slot of the HS-DPCCH sub-frame. The CQI, and in case the UE is configured in MIMO mode also the PCI, are carried in the second and third slot of a HS-DPCCH sub-frame. There is at most one HS-DPCCH on each radio link. The HS-DPCCH can only exist together with an uplink DPCCH. The timing of the HS-DPCCH relative to the uplink DPCCH is shown in section 7.7.

One radio frame T f = 10 ms

s lot

Figure 2A: Frame structure for uplink HS-DPCCH

The spreading factor of the HS-DPCCH is 256 i.e. there are 10 bits per uplink HS-DPCCH slot. The slot format for

uplink HS-DPCCH is defined in Table 5A.

Table 5A : HS-DPCCH fields

5.2.1.3 E-DPCCH and E-DPDCH

The E-DPDCH is used to carry the E-DCH transport channel. There may be zero, one, or several E-DPDCH on each radio link.

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14 Release 9 The E-DPCCH is a physical channel used to transmit control information associated with the E-DCH. There is at most one E-DPCCH on each radio link.

E-DPDCH and E-DPCCH are always transmitted simultaneously, except for the following cases when E-DPCCH is transmitted without E-DPDCH:

- when E-DPDCH but not E-DPCCH is DTXed due to power scaling as described in [5] section 5.1.2.6, or - during the n dtx E-DPDCH idle slots if n max >n tx1 as described in [3] section 4.4.5.2. E-DPCCH shall not be transmitted in a slot unless DPCCH is also transmitted in the same slot.

Figure 2B shows the E-DPDCH and E-DPCCH (sub)frame structure. Each radio frame is divided in 5 subframes, each of length 2 ms; the first subframe starts at the start of each radio frame and the 5th subframe ends at the end of each radio frame.

An E-DPDCH may use BPSK or 4PAM modulation symbols. In figure 2B, M is the number of bits per modulation symbol i.e. M=1 for BPSK and M=2 for 4PAM.

The E-DPDCH slot formats, corresponding rates and number of bits are specified in Table 5B. The E-DPCCH slot format is listed in Table 5C.

slot data 1 radio frame, T f = 10 ms

E-DPDCH

E-DPCCH

Figure 2B: E-DPDCH frame structure

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Table 5C: E-DPCCH slot formats

5.2.2

Common uplink physical channels

5.2.2.1

Physical Random Access Channel (PRACH)

The Physical Random Access Channel (PRACH) is used to carry the RACH.

5.2.2.1.1 Overall structure of random-access transmission

The random-access transmission is based on a Slotted ALOHA approach with fast acquisition indication. The UE can start the random-access transmission at the beginning of a number of well-defined time intervals, denoted access slots. There are 15 access slots per two frames and they are spaced 5120 chips apart, see figure 3. The timing of the access slots and the acquisition indication is described in subclause 7.3. Information on what access slots are available for random-access transmission is given by higher layers.

Access slot

Figure 3: RACH access slot numbers and their spacing

The structure of the random-access transmission is shown in figure 4. The random-access transmission consists of one or several preambles of length 4096 chips and a message of length 10 ms or 20 ms.

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Message part

Preamble 4096 chips

10 ms (one radio frame)

Preamble Preamble Message part Preamble 4096 chips

20 ms (two radio frames)

Preamble Preamble

Figure 4: Structure of the random-access transmission

5.2.2.1.2 RACH preamble part

Each preamble is of length 4096 chips and consists of 256 repetitions of a signature of length 16 chips. There are a maximum of 16 available signatures, see [4] for more details.

5.2.2.1.3 RACH message part

Figure 5 shows the structure of the random-access message part radio frame. The 10 ms message part radio frame is split into 15 slots, each of length T slot = 2560 chips. Each slot consists of two parts, a data part to which the RACH transport channel is mapped and a control part that carries Layer 1 control information. The data and control parts are transmitted in parallel. A 10 ms message part consists of one message part radio frame, while a 20 ms message part consists of two consecutive 10 ms message part radio frames. The message part length is equal to the Transmission Time Interval of the RACH Transport channel in use. This TTI length is configured by higher layers.

The data part consists of 10*2k bits, where k=0,1,2,3. This corresponds to a spreading factor of 256, 128, 64, and 32 respectively for the message data part.

The control part consists of 8 known pilot bits to support channel estimation for coherent detection and 2 TFCI bits. This corresponds to a spreading factor of 256 for the message control part. The pilot bit pattern is described in table 8. The total number of TFCI bits in the random-access message is 15*2 = 30. The TFCI of a radio frame indicates the transport format of the RACH transport channel mapped to the simultaneously transmitted message part radio frame. In case of a 20 ms PRACH message part, the TFCI is repeated in the second radio frame.

Data N data bits

RACH Data Control

Figure 5: Structure of the random-access message part radio frame

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Table 6: Random-access message data fields

Table 7: Random-access message control fields

5.2.2.2 Void

5.3 Downlink physical channels

5.3.1 Downlink transmit diversity

Table 10 summarises the possible application of open and closed loop transmit diversity modes on different downlink physical channel types. Simultaneous use of STTD and closed loop modes on the same physical channel is not allowed. In addition, if Tx diversity is applied on any of the downlink physical channels allocated to a UE(s) that is configured to use P-CPICH as a phase reference on both antennas, then Tx diversity shall also be applied on P-CCPCH and SCH. If Tx diversity is applied on SCH it shall also be applied on P-CCPCH and vice versa. Regarding CPICH transmission in case of transmit diversity used on SCH and P-CCPCH, see subclause 5.3.3.1.

With respect to the usage of Tx diversity for DPCH or F-DPCH on different radio links within an active set, the following rules apply:

- Different Tx diversity modes (STTD and closed loop) shall not be used on the radio links within one active set.

- No Tx diversity on one or more radio links shall not prevent UTRAN to use Tx diversity on other radio links within the same active set.

3GPP

Release 9

18

3GPP TS 25.211 V9.1.0 (2009-12)

- If STTD is activated on one or several radio links in the active set, the UE shall operate STTD on only those radio links where STTD has been activated. Higher layers inform the UE about the usage of STTD on the

individual radio links in the active set.

- Regarding the usage of Tx diversity for DPCH on different radio links within an active set, if closed loop TX diversity is activated on one or several radio links in the active set, the UE shall operate closed loop TX diversity on only those radio links where closed loop TX diversity has been activated. Higher layers inform the UE about the usage of closed loop TX diversity on the individual radio links in the active set.

Furthermore, if the UE is not configured in MIMO mode in a cell the following restrictions apply in this cell:

?If a DPCH is associated with an HS-PDSCH subframe in the same cell, the transmit diversity mode used for the HS-PDSCH subframe shall be the same as the transmit diversity mode used for the DPCH associated with this HS-PDSCH subframe.

?If an F-DPCH is associated with an HS-PDSCH subframe in the same cell, the transmit diversity mode used for the HS-PDSCH subframe shall be the same as the transmit diversity mode signalled for the F-DPCH

associated with this HS-PDSCH subframe.

?If neither DPCH nor F-DPCH is associated with an HS-PDSCH subframe the transmit diversity mode used for the HS-PDSCH subframe shall be the STTD if the P-CCPCH in the cell is using transmit diversity. Otherwise, no transmit diversity is used for the HS-PDSCH subframe.

?If the UE is configured with a secondary serving HS-DSCH cell not associated with either DPCH or F-DPCH in the same cell, the diversity mode used for the HS-PDSCH subframe of that cell is configured by higher

layers and independent from that used in the serving HS-DSCH cell.

If the UE is configured in MIMO mode in a cell then a DPCH or F-DPCH associated with an HS-PDSCH subframe can be either in transmit diversity mode or in no transmit diversity mode in this cell.

Regardless of whether or not the UE is configured in MIMO mode in a cell,

?If the DPCH associated with an HS-SCCH subframe in the same cell is using either open or closed loop transmit diversity on the radio link transmitted from the HS-DSCH serving cell, the HS-SCCH subframe from this cell shall be transmitted using STTD, otherwise no transmit diversity shall be used for this HS-SCCH

subframe.

?If an F-DPCH for which STTD is signalled is associated with an HS-SCCH subframe in the same cell, the HS-SCCH subframe shall be transmitted using STTD, otherwise no transmit diversity shall be used for this HS-

SCCH subframe.

?If neither DPCH nor F-DPCH is associated with an HS-SCCH subframe the transmit diversity mode used for the HS-SCCH subframe shall be the STTD if the P-CCPCH in the cell is using transmit diversity. Otherwise, no transmit diversity is used for the HS-SCCH subframe.

?If the UE is configured with a secondary serving HS-DSCH cell not associated with either DPCH or F-DPCH in the same cell, the diversity mode used for the HS-SCCH subframe of that cell is configured by higher layers and independent from that used in the serving HS-DSCH cell.

The transmit diversity mode on the associated DPCH or F-DPCH may not change during a HS-SCCH and or HS-PDSCH subframe and within the slot prior to the HS-SCCH subframe. This includes any change between no Tx diversity and either open loop or closed loop mode.

If the UE is receiving a DPCH on which transmit diversity is used from a cell, or if the UE is receiving an F-DPCH for which STTD is signalled from a cell, the UE shall assume that the E-AGCH, E-RGCH, and E-HICH from the same cell are transmitted using STTD.

3GPP

3GPP

3GPP TS 25.211 V9.1.0 (2009-12)

19 Release 9 Table 10: Application of Tx diversity modes on downlink physical channel types

"X" – can be applied, "–" – not applied

NOTE *1: T NOTE *2: T he MIMO mode can be configured independently across cells.

5.3.1.1

Open loop transmit diversity

5.3.1.1.1

Space time block coding based transmit antenna diversity (STTD)

The open loop downlink transmit diversity employs a space time block coding based transmit diversity (STTD). The STTD encoding is optional in UTRAN. STTD support is mandatory at the UE.

A block diagram of a generic STTD encoder is shown in the figure 8, figure 8A and figure 8

B below. Channel coding, rate matching and interleaving are done as in the non-diversity mode. For QPSK, the STTD encoder operates on 4 symbols b 0, b 1, b 2, b 3 as shown in figure 8. For AICH, E-RGCH, E-HICH the i b are real valued signals, and i b is defined as i b . For channels other than AICH, E-RGCH, E-HICH the i b are 3-valued digits, taking the values 0, 1, "DTX", and i b is defined as follows: if i b = 0 then i b = 1, if i b = 1 then i b = 0, otherwise i b = i b .

Antenna 1

Antenna 2

STTD encoded symbols for antenna 1 and antenna 2.

Figure 8: Generic block diagram of the STTD encoder for QPSK

3GPP

3GPP TS 25.211 V9.1.0 (2009-12)

20 Release 9

For 16QAM, STTD operates on blocks of 8 consecutive symbols b 0, b 1, b 2, b 3, b 4, b 5, b 6, b 7 as shown in figure 8A below.

Antenna 1

Symbols

STTD encoded symbols for

antenna 1 and antenna 2

Figure 8A: Generic block diagram of the STTD encoder for 16QAM

For 64QAM, STTD operates on blocks of 12 consecutive symbols b 0, b 1, b 2, b 3, b 4, b 5, b 6, b 7, b 8, b 9, b 10, b 11 as shown in figure 8B below.

(完整版)IEEE.802.15.4网络协议栈及物理层

IEEE.802.15.4网络协议栈及物理层 IEEE 802.15.4网络协议栈基于开放系统互连模型(OSI),如图5-4所示,每一层都;实现一部分通信功能,并向高层提供服务。 IEEE 802.15.4标准只定义了PHY层和数据链路层的MAC子层。PHY层由射频收发器以及底层的控制模块构成。MAC子层为高层访问物理信道提供点到点通信的服务接口。 MAC子层以上的几个层次,包括特定服务的聚合子层(service specific convergence sublayer, SSCS),链路控制子层(logical link control , LLC)等,只是IEEE 802.15.4标准可能的上层协议,并不在IEEE 802.15.4标准的定义范围之内。SSCS为IEEE 802.15.4的MAC层接入IEEE 802.2标准中定义的LLC子层提供聚合服务。LLC子层可以使用SSCS的服务接口访问IEEE 802.15.4网络,为应用层提供链路层服务。 5.3.1物理层 物理层定义了物理无线信道和MAC子层之间的接口,提供物理层数据服务和物理层管理服务。物理层数据服务从无线物理信道上收发数据,物理层管理服务维护一个由物理层相关数据组成的数据库。 物理层数据服务包括以下五方面的功能: (1)激活和休眠射频收发器; (2)信道能量检测(energy detect); (3)检测接收数据包的链路质量指示(link quality indication , LQI); (4)空闲信道评估(clear channel assessment, CCA); (5)收发数据。 信道能量检测为网络层提供信道选择依据。它主要测量目标信道中接收信号的功率强度,由于这个检测本身不进行解码操作,所以检测结果是有效信号功率和噪声信号功率之和。 链路质量指示为网络层或应用层提供接收数据帧时无线信号的强度和质量信息,与信道能量检测不同的是,它要对信号进行解码,生成的是一个信噪比指标。这个信噪比指标和物理层数据单元一道提交给上层处理。 空闲信道评估判断信道是否空闲。IEEE 802.15.4定义了三种空闲信道评估模式:第一种简单判断信道的信号能量,当信号能量低于某一门限值就认为信道空闲;第二种是通过判断无线信号的特征,这个特征主要包括两方面,即扩频信号特征和载波频率;第三种模式是前两种模式的综合,同时检测信号强度和信号特征,给出信道空闲判断。 1.物理层的载波调制

802.15.4协议规范(物理层)

802.15.4协议规范(物理层) IEEE802.15.4-2003协议规范规定了一个MAC层和两个PHY层。802.15.4的主要协议框架如图所示。这边只介绍物理层。 802.15.4协议架构 1.协议概述 在LR WPAN(无线个人区域网)中,存在两种不同类型的设备,一种是完整功能设备(FFD),一种是简化功能设备(RFD)。FFD可以同时和多个RFD或FFD进行通信,所以常作为协调器,而RFD只能和一个FFD进行通信。一个网络中至少有一个FFD作为PAN 主协调器。 LR WPAN网络中根据不同需要有两种网络拓扑结构:星型拓扑结构和对等拓扑结构。星型拓扑结构由一个叫做PAN主协调器的中央控制器和多个从设备组成,主协调器必须是一个具有完整功能的设备,从设备可以是FFD也可以是RFD。在对等拓扑结构中,每一个设备都可以与在无线通信范围内的其他任何设备进行通信,任何一个设备都可以定义为PAN 主协调器。无论是星型拓扑还是对等拓扑网络结构。每一个独立的PAN都以一个标识符以确保唯一性。在设备发起连接时,可采用64位的长地址,只有在连接成功时,系统分配了PAN的标识符后,才能采用16位的短地址码进行连接。 在LR WPAN中,允许有选择性的使用超帧结构,超帧的格式由主协调器来定义,它分为16个大小相等的时隙,其中第一个时隙为PAN的信标帧。任何从设备如果想在两个信标之间的竞争接入期间(CAP)进行通信,则需要使用具有时隙和免冲突载波检测多路接入(CSMA CA)机制同其他设备进行竞争通信。 在一些特殊情况下,可采用PAN主协调器的超帧中的一部分来完成这些特殊要求。这部分称为保护时隙(GTS)。多个保护时隙构成一个免竞争时期(CFP),但最多可分配7个GTS。因为有足够的CAP空间保证为其他网络设备和其他希望加入网络的新设备提供竞争接入的机会。有无GTS的超帧结构分别如下所示。

计算机网络原理 物理层接口与协议

计算机网络原理物理层接口与协议 物理层位于OSI参与模型的最低层,它直接面向实际承担数据传输的物理媒体(即信道)。物理层的传输单位为比特。物理层是指在物理媒体之上为数据链路层提供一个原始比特流的物理连接。 物理层协议规定了与建立、连接和释放物理信道所需的机械的、电气的、功能性的和规和程性的特性。其作用是确保比特流能在物理信道上传输。 图3-1 DTC-DCE接口 ISO对OSI模型的物理层所做的定义为:在物理信道实体之间合理地通过中间系统,为比特传输所需的物理连接的激活、保持和去除提供机械的、电气的、功能性和规程性的手段。比特流传输可以采用异步传输,也可以采用同步传输完成。 另外,CCITT在X.25建议书第一级(物理级)中也做了类似的定义:利用物理的、电气的、功能的和规程的特性在DTE和DCE之间实现对物理信道的建立、保持和拆除功能。这里的DTE(Date Terminal Equipment)指的是数据终端设备,是对属于用户所有的连网设备或工作站的统称,它们是通信的信源或信宿,如计算机、终端等;DCE(Date Circuit Terminating Equipment 或Date Communications Equipment),指的是数据电路终接设备或数据通信设备,是对为用户提供入接点的网络设备的统称,如自动呼叫应答设备、调制解调器等。 DTE-DCE的接口框如图3-1所示,物理层接口协议实际上是DTE和DCE或其它通信设备之间的一组约定,主要解决网络节点与物理信道如何连接的问题。物理层协议规定了标准接口的机械连接特性、电气信号特性、信号功能特性以及交换电路的规程特性,这样做的主要目的,是为了便于不同的制造厂家能够根据公认的标准各自独立地制造设备。使各个厂家的产品都能够相互兼容。 1.机械特性 规定了物理连接时对插头和插座的几何尺寸、插针或插孔芯数及排列方式、锁定装置形式等。 图3-2 常见连接机械特征 图形3-2列出了各类已被ISO标准化了的DCE连接器的几何尺寸及插孔芯数和排列方式。一般来说,DTE的连接器常用插针形式,其几何尺寸与DCE连接器相配合,插针芯数和排列方式与DCE连接器成镜像对称。 2.电气特性 规定了在物理连接上导线的电气连接及有关的电咱路的特性,一般包括:接收器和发送器电路特性的说明、表示信号状态的电压/电流电平的识别、最大传输速率的说明、以及与互连电缆相关的规则等。 物理层的电气特性还规定了DTE-DCE接口线的信号电平、发送器的输出阻抗、接收器的输入阻抗等电器参数。

WCDMA物理层协议TS25211-910

3GPP TS 25.211 V9.1.0 (2009-12) Technical Specification 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Physical channels and mapping of transport channels onto physical channels (FDD) (Release 9) The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP. The present document has not been subject to any approval process by the 3GPP Organisational Partners and shall not be implemented. This Specification is provided for future development work within 3GPP only. The Organisational Partners accept no liability for any use of this Specification. Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organisational Partners' Publications Offices.

什么是物理层协议

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什么是物理层协议 篇一:计算机网络原理物理层接口与协议 计算机网络原理物理层接口与协议 物理层位于osi参与模型的最低层,它直接面向实际承 担数据传输的物理媒体(即信道)。物理层的传输单位为比特。物理层是指在物理媒体之上为数据链路层提供一个原始比 特流的物理连接。 物理层协议规定了与建立、连接和释放物理信道所需的 机械的、电气的、功能性的和规和程性的特性。其作用是确 保比特流能在物理信道上传输。 图3-1dtc-dce 接口 iso对osi模型的物理层所做的定义为:在物理信道实 体之间合理地通过中间系统,为比特传输所需的物理连接的 激活、保持和去除提供机械的、电气的、功能性和规程性的 手段。比特流传输可以采用异步传输,也可以采用同步传输 完成。 另外,ccitt在x.25建议书第一级(物理级)中也做了 类似的定义:利用物理的、电气的、功能的和规程的特性在

dte和dce之间实现对物理信道的建立、保持和拆除功能。 这里的dte(dateterminalequipment) 指的是数据终端设备, 是对属于用户所有的连网设备或工作站的统称,它们是通信 的信源或信宿,如计算机、终端等; dce(datecircuitterminatingequipment 或 datecommunicationsequipment) , 指的是数据电路终接设备 或数据通信设备,是对为用户提供入接点的网络设备的统称, 如自动呼叫应答设备、调制解调器等。 dte-dce的接口框如图3-1所示,物理层接口协议实际 上是dte和dce或其它通信设备之间的一组约定,主要解决 网络节点与物理信道如何连接的问题。物理层协议规定了标 准接口的机械连接特性、电气信号特性、信号功能特性以及交换电路的规程特性,这样做的主要目的,是为了便于不同的制造厂家能够根据公认的标准各自独立地制造设备。使各个厂家的产品都能够相互兼容。 1.机械特性 规定了物理连接时对插头和插座的几何尺寸、插针或插 孔芯数及排列方式、锁定装置形式等。 图3-2常见连接机械特征 图形3-2列出了各类已被iso标准化了的dce连接器的 几何尺寸及插孔芯数和排列方式。一般来说,dte的连接器 常用插针形式,其几何尺寸与dce连接器相配合,插针芯数

什么是物理层协议

竭诚为您提供优质文档/双击可除 什么是物理层协议 篇一:计算机网络原理物理层接口与协议 计算机网络原理物理层接口与协议 物理层位于osi参与模型的最低层,它直接面向实际承担数据传输的物理媒体(即信道)。物理层的传输单位为比特。物理层是指在物理媒体之上为数据链路层提供一个原始比 特流的物理连接。 物理层协议规定了与建立、连接和释放物理信道所需的机械的、电气的、功能性的和规和程性的特性。其作用是确保比特流能在物理信道上传输。 图3-1dtc-dce接口 iso对osi模型的物理层所做的定义为:在物理信道实 体之间合理地通过中间系统,为比特传输所需的物理连接的激活、保持和去除提供机械的、电气的、功能性和规程性的手段。比特流传输可以采用异步传输,也可以采用同步传输完成。 另外,ccitt在x.25建议书第一级(物理级)中也做了类似的定义:利用物理的、电气的、功能的和规程的特性在

dte和dce之间实现对物理信道的建立、保持和拆除功能。 这里的dte(dateterminalequipment)指的是数据终端设备,是对属于用户所有的连网设备或工作站的统称,它们是通信的信源或信宿,如计算机、终端等; dce(datecircuitterminatingequipment或datecommunicationsequipment),指的是数据电路终接设备或数据通信设备,是对为用户提供入接点的网络设备的统称,如自动呼叫应答设备、调制解调器等。 dte-dce的接口框如图3-1所示,物理层接口协议实际 上是dte和dce或其它通信设备之间的一组约定,主要解决网络节点与物理信道如何连接的问题。物理层协议规定了标准接口的机械连接特性、电气信号特性、信号功能特性以及交换电路的规程特性,这样做的主要目的,是为了便于不同的制造厂家能够根据公认的标准各自独立地制造设备。使各个厂家的产品都能够相互兼容。 1.机械特性 规定了物理连接时对插头和插座的几何尺寸、插针或插孔芯数及排列方式、锁定装置形式等。 图3-2常见连接机械特征 图形3-2列出了各类已被iso标准化了的dce连接器的几何尺寸及插孔芯数和排列方式。一般来说,dte的连接器 常用插针形式,其几何尺寸与dce连接器相配合,插针芯数

LTE物理层协议书

4.13 信道可能 4.13.1 信道可能简介 1.有哪些信道可能方法 (1) 盲可能与半盲可能 (2) 基于导频的信道可能 (3)基于训练序列的信道可能 2.信道可能的作用 (1)抵抗衰落,用可能结果来抵消各个 子信道衰落的阻碍,从而在接收端 获得正确的解调。 (2)在OFDM无线通信系统中一般采纳 多进制调制方式,如MQAM调制方 式,这就需要在接收端进行相干解 调。由于无线信道的传输特性是随

时刻变化的,因此相干解调就要用 到信道的瞬时状态信息,因此在系 统接收端需要进行信道可能,以获 得无线信道的瞬时传输特性 (3)信道可能还能够用来纠正频率偏移 造成的信号正交性的破坏 (4)关于结合MIMO技术的OFDM系统来 讲,空时检测或空时解码一般要求 己知信道状态信息,因此这时的信 道可能及可能的准确性就尤为重要 (5)关于闭环系统,如OFDM自适应调制 系统、MIMO一OFDM自适应调制系 统、结合信道信息采纳改进空时编 码发射机的MIMO系统等,发射机端 同样要求得到信道状态信息 3.各种方法的差不多原理及准则 原理(1)盲可能:不需要发送辊发送专 门的训练序列,然而接收须接

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