DE10315058A1 - Data transmission method - Google Patents

Abstract

The invention relates to a method for transmitting data on a common radio channel, which is provided between a base station (BS) and a plurality of terminals (UE) in a UMTS communication system in FDD mode as a common random access channel (HS-PRACH) becomes. Here, in the case of a shared random access channel (HS-PRACH) for an uplink transmission, a common control channel (HS-S-CCPCH) is to be used as a return channel for transmission power control in a packet-oriented transmission. Upon successful completion of a request to use the common random access channel using a preamble part, the terminal sends a message part on the common uplink transmission channel. Confirmations (ACK, NACK) of the receipt of data are sent back to the terminal from the base station via the common control channel. The terminal sets the transmission power based on the content of the confirmation. At least one of the following parameters is used for setting: a performance increase parameter, a repetition parameter, a performance increase threshold parameter, a performance decrease parameter and a performance decrease threshold parameter.

Description

The The invention relates to a method for transmitting data via a radio channel shared by several terminals, on which the transmission power is regulated. Furthermore, the Invention a terminal, a base station and a communication system.

In so-called CDMA (Code Division Multiple Access) communication systems, where all participants share the same frequency spectrum and only by different codes (see section Definitions) distinguish must be guaranteed be that a terminal near the base station does not receive the signal overlaid by more distant terminals. For this reason, a dynamic power control or "power control" is carried out. For that are on the dedicated channels special bits are provided with which a terminal provides feedback can send to the base station, e.g. those with poor reception an increase in performance through the base station. On the other hand sends the base station sends control bits to the respective terminals and requests to maintain each individual terminal to increase the transmission power or lower.

This closed power setting exists only on the dedicated channels and not on the shared channels.

The problem with common channels is described below using an example of a communication system operating according to the UMTS (Universal Mobile Telecommunications System) standard. For a more detailed explanation or clarification of terms, please refer to the description of the figures:
Currently, two types of physical channels are specified in the FDD mode for packet data transmission for the uplink: the assigned physical data channel or "Dedicated Physical Data Channel" DPDCH and the physical random access channel or "Physical Random Access Channel" PRACH. The DPDCH allows maximum packet data transfer rates of up to 5.76 Mbps (megabits per second) as a gross data rate, but this channel is not ideal for intermittent data traffic, as is typical for packet data transfers, since it takes a relatively long time to set up and tear down the channel. The common channel PRACH, on the other hand, is designed for burst-like packet data traffic, but the PRACH only allows maximum data rates of up to 120 kbps (kilobits per second) as a gross data rate. In the case of a packet data connection to be set up between the terminal UE and the UMTS network UTRAN, depending on the current traffic situation in the radio cell and the requested quality of service or "Quality of Service" QoS of the terminal, either UTRAN allocates dedicated or shared radio resources.

in the UMTS FDD mode enables the common channel PRACH the uplink transmission of burst-like Data traffic, which signaling information or user data can contain up to 120 kilo bits per second (kbps) as a gross data rate. Maximum can up to 16 PRACHs can be configured in one cell. The configuration the PRACHs is in the system information blocks or "system information blocks" (SIB) 5 or 6 above the Broadcast channel BCH transmitted in the cell. Within SIB 5 / SIB 6 will be the configuration for each PRACH is specified in the information element or "information element" (IE) "PRACH system information list".

table 1 shows the list of information elements in the “PRACH system information list ".

Table 1: Information elements of the "PRACH system information list" according to UMTS Release 5

• – PRACH info: Hierbei wird die Konfiguration des PRACHs hinsichtlich der verfügbaren Signaturen, Zugriffszeitschlitze bzw. "Access Slots" AS, Spreizfaktoren SF für den Datenteil sowie des für die Präambel verwendeten Verwürfel- bzw. "Scrambling"-Codes signalisiert;
• – Transport channel identity: Gibt die Identität des RACH-Transportkanals an, welcher auf den PRACH abgebildet ist;
• – RACH TFS: Gibt die Menge der erlaubten Transportformate für den konfigurierten RACH an;
• – RACH TFCS: Gibt die Menge der erlaubten Transportformat-Kombinationen für den konfigurierten RACH an;
• – PRACH partitioning: Basierend auf die im IE "PRACH Info" konfigurierten Signaturen und Zugriffszeitschlitze AS werden in diesem Informationselement bis zu acht Zugriffsserviceklassen ASC signalisiert. In jeder ASC kann jeweils eine Untermenge von den insgesamt verfügbaren Signaturen und Zugriffszeitschlitze konfiguriert werden, so dass eine ASC eine Unterteilung bzw. Partition der PRACH-Ressourcen darstellt;
• – Persistence scaling factors: Gibt die Ubertragungswahrscheinlichkeiten an, mit der eine RACH-Übertragungsprozedur von der MAC-Protokollschicht gestartet wird;
• – AC-to-ASC mapping table: Hiermit wird die Abbildung der Access Classes zu den Access Service Classes signalisiert, mit der ein "idle mode"-Terminal UE in der Lage ist, eine initiale Nachricht im Uplink zu senden;
• – Primary CPICH DL TX power: Die Leistung mit der der P-CPICH in der Funkzelle gesendet wird, wird zur Berechnung der initialen Ausgangsleistung der PRACH-Präambel herangezogen;
• – Constant value: Konstanter Wert, der zur Berechnung der initialen Ausgangsleistung der PRACH Präambel herangezogen wird;
• – PRACH power offset: Gibt die Parameter für die PRACH Präambelübertragung an, wie die Schrittweite für die Leistungseinstellung und die maximale Anzahl der Präambel-Retransmissionen;
• – RACH transmission parameters: Gibt die Parameter zur Kontrolle der RACH-Übertragung auf der MAC-Protokollschicht-Ebene an, weitere Details sind im Zusammenhang mit Tabelle 4 näher erläutert;
• – AICH info: Gibt die Parameter für den jeweiligen PRACH assozierten AICH an.

The function or meaning of the individual information elements is as follows:

• - PRACH info: The configuration of the PRACH is signaled with regard to the available signatures, access time slots or "access slots" AS, spreading factors SF for the data part and the scrambling or "scrambling" code used for the preamble;
• - Transport channel identity: specifies the identity of the RACH transport channel, which is mapped to the PRACH;
• - RACH TFS: Specifies the number of permitted transport formats for the configured RACH;
• - RACH TFCS: Specifies the number of permitted transport format combinations for the configured RACH;
• - PRACH partitioning: Based on the signatures and access time slots AS configured in IE "PRACH Info", up to eight access service classes ASC are signaled in this information element. A subset of the total available signatures and access time slots can be configured in each ASC, so that an ASC represents a subdivision or partition of the PRACH resources;
• Persistence scaling factors: specifies the transmission probabilities with which an RACH transmission procedure is started by the MAC protocol layer;
• - AC-to-ASC mapping table: This signals the mapping of the access classes to the access service classes, with which an "idle mode" terminal UE is able to send an initial message in the uplink;
• - Primary CPICH DL TX power: The power with which the P-CPICH is sent in the radio cell is used to calculate the initial output power of the PRACH preamble;
• - Constant value: Constant value that is used to calculate the initial output power of the PRACH preamble;
• - PRACH power offset: Specifies the parameters for the PRACH preamble transmission, such as the step size for the power setting and the maximum number of preamble retransmissions;
• - RACH transmission parameters: Specifies the parameters for controlling the RACH transmission at the MAC protocol layer level, further details are explained in connection with Table 4;
• - AICH info: Indicates the parameters for the respective PRACH associated AICH.

in the Case of a packet data transmission via the PRACH, the terminal UE sends along according to a defined pattern Random components (ALOHA method) first a preamble to UTRAN and listen in a precisely specified time slot on the AICH for a confirmation. The UTRAN can send the value 0, 1, –1 here. A "0" stands for no confirmation, however no rejection. This is the default and is also sent if the UTRAN the preamble could not clearly assign to a terminal UE. A "1" means a confirmation (ACK) and a "-1" a rejection (NRCK). Only after receipt an ACK, the terminal sends data on the PRACH.

The power control or power setting on the PRACH is specified as follows:
A base station sends the parameters for the use of the PRACHs configured in the radio cell on a collective call or "broadcast" channel BCH that can be received by all terminals in the radio cell. By receiving and evaluating this data, each terminal knows with which code and at what time plus a random time interval it can send on the PRACH. An initial service for sending the preamble is also communicated as a parameter. After selecting a specific PRACH, the terminal now sends a preamble with the transmission power specified as the initial power and listens to a confirmation from the network on the AICH in a specific time slot. If the request is rejected, a preamble with the initial service is sent again at another time. If the terminal only receives the default value, which means neither confirmation nor rejection, it sends the preamble again. However, this time with a transmission power increased by a delta that is also specified in the parameters. If a confirmation is given, a data packet can be sent on the PRACH depending on the performance of the last successfully transmitted preamble.

in principle can all terminals UE within a UMTS cell together the PRACHs for data transmission use. The access of the terminals UE to a PRACH is after regulated by the "Slotted ALOHA" process, where each terminal UE randomly selects a suitable PRACH and this only at the beginning of fixed time intervals, the so-called Access time slots or "access slots "(AS), sends. It depends the use of the random chosen PRACHs from the access service classes ASCs (Access Service Classes) from the IE "PRACH partitioning " become. Table 2 shows the parameters with which each ASC is configured becomes. The ASCs regulate a prioritized use of PRACH.

Table 2: Information elements of "PRACH partitioning" for ASC configuration according to UMTS Release 5

The PRACH consists of a preamble part and a message part. The PRACH message part in turn consists of a control part and a data part. The random access transmission consists of one or more preambles of 4096 chips in length and the actual message. A randomly selected signature s is transmitted in the preambles. After a positive confirmation (ACK) for the correct reception of the preamble on the acquisition indicator channel (AICH) by the base station, the terminal UE sends the data on the PRACH message part at a specified time based on the access time slots AS. In 3 an example of a random access transmission is shown, in which the terminal UE receives an ACK from the base station only in the second preamble. Here τ _{p-p is} the timing offset between two preambles, τ _p-m the time offset or "timing offset" between the preamble and PRACH message part and τ _p-a the timing offset between the start of the uplink access time slot in which the terminal UE sends a preamble and the beginning of the corresponding downlink access time slot in which the base station sends the AICH. In the example after 3 a transmission time length of TTI = 10ms was chosen for the PRACH message part. The following values were set for the timing offsets: τ _p-p = τ _p-m = 3 AS and τ _p-a = 1.5 AS, the length of an access time slot AS being 5120 chips.

The The transmission power of the PRACH message part is based on the Transmission power of the successfully sent preamble set. Furthermore become the OVSF channelization codes for the PRACH message section from the successfully transferred Preamble signature certainly. There is a maximum of 16 of these signatures, which are assigned to one of the Show 16 nodes in the OVSF code tree. The signatures correspond with a code with spreading factor SF = 16. Depending on the signature s the code subtree below for the PRACH message part used.

The Number of signatures and uplink access time slots AS that one Terminal UE for data transmission via the PRACH available stand by priority of the ASCs set. Up to to 8 ASCs for a PRACH can be specified, these ASCs are numbered so so that the access service class with the number 0 or "ASC # 0" has the highest priority and the Access service class with the number 7 or "ASC # 7" has the lowest priority. ever higher the priority is, the bigger can be the number of available signatures and the uplink access time slots AS (summarized in the so-called RACH subchannels) must be configured in ASC. In inactive transmission mode or in "Idle Mode" selects the Radio resource control or "radio Resource Control "(RRC) layer in the UE terminal the access service class ASC based on the access classes or "Access Classes" (AC). Both Access classes or "Access Classes " it is a mechanism by which a network operator access from idle mode or "Idle Mode Can control terminals in its radio cell. There are a total of 16 in the UMTS standard ACs specified, for example, the access class allows AC15 only one access from terminals leading to employees of the network operator belong.

• 1. Vor Start der eigentlichen Nachrichtenübertragung sendet die Terminal UE eine zufällig gewählte Präambel der Länge 4096 Chips zum UTRAN. Falls das UTRAN die Präambel kor rekt detektieren kann, sendet es eine positive Bestätigung (ACK) auf dem Akquisitions-Indikator-Kanal bzw. "Acquisition Indicator Channel" AICH zum Terminal UE. Falls das UTRAN die Präambel nicht korrekt detektieren kann, sendet es eine negative Bestätigung (NACK) auf dem AICH zum Terminal UE.
• 2. Es wird angenommen, dass das UTRAN die vom Terminal UE gesendete Präambel nicht korrekt detektieren konnte, so dass ein NACK auf dem AICH zurückgesendet wird.
• 3. Die Terminal UE sendet nach einer zufälligen Wartezeit eine neue zufällig gewählte Präambel zum UTRAN. Dabei wird diese Präambel mit einer etwas höheren Leistung als bei der vorherigen Präambel-Übertragung gesendet.
• 4. Diesmal kann das UTRAN die vom Terminal UE gesendete Präambel korrekt detektieren, so dass ein ACK auf dem AICH zurückgesendet wird.
• 5. Die Sendeleistung für den folgenden PRACH Nachrichtenteil bzw. "message part" wird auf Basis der Sendeleistung der erfolgreich gesendeten Präambel eingestellt. Terminal UE sendet die Nachricht auf dem PRACH Nachrichtenteil zum nächstmöglichen Zeitpunkt zum UTRAN und wartet auf eine Bestätigung über den S-CCPCH.
• 6. Es wird angenommen, dass das UTRAN die vom Terminal UE gesendete Nachricht auf dem PRACH Nachrichtenteil fehlerfrei empfangen konnte, so dass ein ACK über dem S-CCPCH zurückgesendet wird. Damit ist die Zufallszugriffsübertragung beendet.

In 1 is a diagram for the sequence of a random access transmission to be confirmed (on the PRACH) between the terminal and a UTRAN, which runs via the base station BS. The communication system K comprises the UTRAN, the base station BS and the terminal UE.

• 1. Before the actual message transmission starts, the terminal UE sends a randomly selected preamble length of 4096 chips to the UTRAN. If the UTRAN can correctly detect the preamble, it sends a positive confirmation (ACK) on the acquisition indicator channel or "acquisition indicator channel" AICH to the terminal UE. If the UTRAN cannot correctly detect the preamble, it sends a negative confirmation (NACK) on the AICH to the terminal UE.
• 2. It is assumed that the UTRAN could not correctly detect the preamble sent by the UE terminal, so that a NACK is sent back on the AICH.
• 3. After a random waiting time, the terminal UE sends a new, randomly selected preamble to the UTRAN. This preamble is sent with a slightly higher output than in the previous preamble transmission.
• 4. This time the UTRAN can correctly detect the preamble sent by the UE terminal, so that an ACK is sent back on the AICH.
• 5. The transmission power for the following PRACH message part or "message part" is set on the basis of the transmission power of the successfully sent preamble. Terminal UE sends the message on the PRACH message part to the UTRAN as soon as possible and waits for confirmation via the S-CCPCH.
• 6. It is assumed that the UTRAN was able to receive the message sent by the UE terminal on the PRACH message part without errors, so that an ACK is sent back via the S-CCPCH. This completes the random access transfer.

Disadvantageously there is no further performance adjustment until the end of the data transmission. The PRACH is used, among other things, for the initial connection establishment by the Terminal UE used.

In 3 the usual sequence of a random access transmission in UMTS-FDD mode can be seen, in which the terminal UE receives an ACK from the base station only during the second preamble transmission. A time stream is shown for the base station BS and the terminal UE, which is divided into individual access time slots AS. For the base station BS and the terminal UE, a time line is plotted, which is divided into individual time slots. The terminal UE first sends a preamble PA, then wait a time τ _p-p before it sends the preamble PA again with increased power, since it receives neither a positive nor a negative confirmation on the AICH from the base station. Τ _{p – p is} the time offset between two preambles, τ _{p – m is} the time offset between preamble and HS-PRACH message part and, as described below, τ _{p – a is} the time offset between the start of the uplink Access time slot in which the terminal sends a preamble and the beginning of the corresponding downlink access time slot in which the base station sends the AICH.

The base station sends a confirmation (0, +1, -1) via the AICH with a certain time offset or "time offset" TO, the length of which is equal to τ _p-a . In the event of a positive confirmation ACK (+1), the terminal UE then begins to send the PRACH message part PRACH NT, which contains a data part D and a control part C, after a time τ _p-m . In the example after 3 a transmission frame length or a transmission time interval of "TTI = 10 ms" was selected for the PRACH message part. The following values were set for the time offsets: τ _p-p = τ _p-m = 3 access time slots and τ _p-a = 1.5 access time slots, the length of an access time slot 5120 Chips.

How already written, takes place after the initial performance adjustment no further performance adjustment takes place.

outgoing From this prior art it is the object of the present invention a procedure for specify closed power control on shared channels.

This Task is through claims 1, 3, 4 and 5 solved. Advantageous refinements are the subject of the dependent claims.

The Invention is based on the idea of defining parameters by means of who used a power control on one of several terminals Channel can be done.

It is the essence of the invention in a UMTS FDD system in the event that a common random access channel is used for an uplink transmission to use a common control channel as a return channel for transmission power control in a packet-oriented transmission. The proposed common uplink channel is referred to in the registration with HS-PRACH, the ge common control channel as HS-S-CCPCH.

To successful completion of a request to use the common The terminal sends a random access channel using a preamble part a message part on the common uplink transmission channel.

On the Common control channel are confirmed by the base station via the Receiving data back sent to the terminal. Based on the content of the confirmation the terminal enters the transmission power.

to Setting, at least one of the following parameters is used: A performance increase parameter, a repeat parameter, a performance increase threshold parameter Derating parameter and a derating threshold parameter.

So for example, in the event of a negative confirmation (NACK) according to one determined by the performance increase threshold parameter Number of receptions a negative confirmation the transmission power by one by the power increase parameter set value increased. The repetition parameter specifies how often a transmission frame with increased Power is sent.

Analogous can, in the case of reception, a certain one, by the power reduction threshold parameter specified number of positive confirmations (ACK) the transmission power by a value defined by the power reduction parameter be humiliated.

at additional Use of HS-PRACH for an improved uplink connection, especially for bumpy ones Data traffic and distribution over a long period of time can reduce performance be improved so significantly.

On Terminal or a base station, which are suitable for these methods at least with a transceiver and a processor equipped, which cooperate so that a power regulation can be done.

Further Advantages and refinements of the invention are described below explained by figures. It demonstrate:

1 the sequence of a random access transmission in UMTS FDD mode;

2 a frame structure for the uplink PRACH;

3 the sequence of a random access transmission in UMTS FDD mode;

4 the course of a performance increase in a random access transmission in UMTS FDD mode;

5 the process of a power reduction in a random access transmission in UMTS FDD mode.

First of all the terms used in the registration are explained in more detail.

1. Definitions

A communication system or communication network is a structure for exchanging data. This can be a cellular mobile radio network that works, for example, according to the GSM (Global System of Mobile Communications) standard or the UMTS (Universal Mobile Telecommunications System) standard. Terminals and base stations are generally provided in a communication system and connect to one another via a radio interface. In the UMTS, the communication system or radio transmission network has at least base stations, here also called NodeB, and radio network control units or "Radio Network Controllers" (RNC) for connecting the individual base stations. The terrestrial radio access network or "Universal Terrestrial Radio Access Network" (UTRAN) is the radio-technical part of a UMTS network in which, for example, the Radio interface is provided. A radio interface is always standardized and defines the entirety of the physical and protocol specifications for data exchange, for example the modulation method, the bandwidth, the frequency swing, access methods, security procedures or switching techniques. The UTRAN thus comprises at least base stations and at least one RNC.

at cellular Mobile radio systems can. different radio transmission technologies be provided that define how the physical connection resources be divided. In the case of UMTS, there is currently a frequency multiple access mode or frequency Division duplex (FDD) mode is provided, as well as different time multiple access modes or Time Division Duplex (TDD) modes. In FDD mode, this is done data transfer of so-called "up" and "down link" connections different frequencies by frequency division multiplex, while at data transfer in both TDD modes of uplink and downlink on the same frequency by time division he follows.

A Base station is a central unit in a communication network, which in the case of a cellular Cellular network terminals or communication terminals within a cell of the mobile radio network is operated via one or more radio channels. The base station provides the air interface between the base station and terminal ready. It takes over the handling of radio operations with the mobile participants and monitored the physical radio link. It also transmits the user and status messages to the terminals. The base station has no switching function, but just a supply function. A base station comprises at least a transmitting / receiving unit.

On Terminal can be any communication terminal via which a user communicates in a communication system. It fall for example, mobile terminals like cell phones or portable computers with a radio module underneath. A terminal is often also referred to as a "mobile station" (MS) or in UMTS "user equipment" (UE).

in the Mobile radio is differentiated between two connection directions. The downlink or "Downlink" (DL) the direction of transmission from the base station to the terminal. The uplink or "uplink" (UL) designated the opposite direction of transmission from the terminal to the base station.

In Wideband transmission systems, such as a UMTS cellular network, a channel is a sub-area one available standing total transmission capacity. As a radio channel becomes a wireless communication path in the context of this application designated.

In a mobile radio system, for example UMTS, is available for the transmission Two types of physical channels of data: dedicated channels or "dedicated channels" and "common channels". With the dedicated Channels become a physical resource only for the transmission of information for a certain terminal reserved. The common channels can transmit information be the for all terminals are thought of, for example the primary common physical control channel or "primary common control physical channel" (P-CCPCH) in the downlink, or all terminals share a physical resource, by allowing each terminal to use it only for a short time. This is for example in the case of the physical random access channel or "physical random access Channel "(PRACH) the case in the uplink.

at The data is transmitted via a "Common Channel" or "Dedicated Channel" in addition to bandwidth spreading using a spreading code or "channelization code" for more robust transmission additionally a scramble or "scrambling" procedure for identification subjected to a specific connection. To do this will depend the direction of transmission, of the channel type and radio transmission technology different types of scramble codes or "scrambling codes ".

During a Bit from a data sequence is usually referred to as a symbol a bit of a bandwidth-spread sequence called a chip.

In Mobile radio systems, such as those based on UMTS, In addition to circuit-switched or "circuit switched" services, packet-oriented or "packet switched" services are also provided.

In particular in mobile radio systems of the 2nd or 3rd generation, such as the GSM or UMTS, the data transmission via the radio channel generally takes place in a predetermined time structure, the transmission frame, which is often also referred to as a frame. A transmission frame provides that is, the periodic basic time structure with which data is physically transmitted. In UMTS, a frame is 10 ms. To carry out certain functions, such as channel estimation and performance control, a frame is divided into time slots, for example in UMTS into 15 time slots. A time slot is therefore a permanently assigned time segment within a transmission frame.

On Basis of the temporal structure, consisting of frames and time slots, you can use other temporal substructures, for example subframes or "Subframes". For example could one defines a subframe in UMTS, the three time slots should include, so that a frame is then composed of 5 subframes.

A transmission frame length or a transmission time interval or "transmission time interval "(TTI) denotes the length of time over which Data that was encoded together due to scrambling, e.g. a so-called "scrambling" or "interleaving", spread out over time become. For example, a TTI can be specified in terms of time slots become.

In order to the transmission time interval, in the data from the medium access layer or "Medium Access Layer" (MAC) (OSI layer 2, OSI: Open System Interconnecti-on) to the physical layer (OSI layer 1) in Form of so-called transport blocks (= Combination of data packets of fixed length) are transmitted his. Furthermore, the transmission time interval, in to which the data is then physically transferred transmit the air interface will be designated.

For example in the case for the TTI = 40ms applies, data is from the MAC layer every 40ms sent to the physical layer. On the other hand, this data then transmitted from the physical layer within 4 frames.

2. Refinements the invention

2.1 Combination of the power control parameters with shortened frame formats

A possible Extension for more efficient data transmission on the HS-PRACH is the segmentation of a data packet into several smaller sections, those within a specified section at a random time be sent. There is a confirmation of the receipt of the individual segments via the HS-S-CCPCH. In the event of a failed confirmation within a specified one Time the segment is repeated. The total length for the transmission of a packet can thereby increase significantly. The longer a data transfer the more important the use of a closed one becomes Power control.

2.2 Specification of the Power control parameters

Becomes the HS-PRACH as an additional Data connection used to reduce interference in the cell is according to one advantageous embodiment of an expansion of the secondary common Control channel or "Secondary Common Control Physical Channel "(S-CCPCH), namely hereinafter referred to as high-speed channel or HS-S-CCPCH Channel, as a separate return channel for one advanced performance control during the data transmission used.

Essential for one Design of the method according to the invention is an efficient power control for the shared channel PRACH in UMTS FDD mode, particularly advantageous in the case of shortened frame lengths. in the the following is an embodiment proposed with the following features:

a) Extension of the ASC with new parameters

• – Ein Leistungserhöhungsparameter "PowerUp NACK "Delta" (PND): Stellt ein Delta in der Einheit dBm ein, um das im Falle des Empfangs von NACK die Leistung erhöht wird.
• – Ein Leistungserhöhungswiederholparameter "PowerUp NACK Repeat" (PNR): Stellt die Anzahl der Wiederholungen mit Leistungserhöhung im Falle des Empfangs von NACK ein.
• – Eine Leistungserhöhungsschwelle "PowerUp Treshold" (PUT): Stellt die aufeinanderfolgende Anzahl der empfangenen NACKs ein, bei der die Leistung erhöht wird.
• – Ein Leistungserniedrigungsparameter "PowerDown Delta" (PDD): Stellt ein Delta in der Einheit dBm ein, um das im Falle des Empfangs von ACK die Leistung gesenkt wird.
• – Eine Leistungserniedrigungsschwelle „PowerDown Treshold" (PDT): Stellt die aufeinanderfolgende Anzahl der empfangenen ACKs ein, bei der die Leistung gesenkt wird.

Within the information element "PRACH system information list" (table 1) in the IE "PRACH partitioning" (table 2) the ASC configuration is expanded by the following five parameters:

• - A power increase parameter "PowerUp NACK" Delta "(PND): Sets a delta in dBm by which the power is increased if NACK is received.
• - A power increase repeat parameter "PowerUp NACK Repeat" (PNR): Sets the number of repetitions with power increase when NACK is received.
• - A PowerUp Threshold (PUT): Sets the successive number of NACKs received at which the power is increased.
• - A power reduction parameter "PowerDown Delta" (PDD): sets a delta in dBm, by which the performance is reduced if ACK is received.
• - A PowerDown Threshold (PDT): Sets the successive number of ACKs received at which the power is reduced.

table 3 shows the expanded information element IE “PRACH partitioning” for ASC configuration with the corresponding value ranges of the new parameters. According to one advantageous embodiment can all Parameters or only a selection from them can be provided.

Table 3

Table 3

b) Performance control or power setting on the PRACH

When a specified number of NACKs (hysteresis) are received, the data packet segment is repeated with the power increased by the value specified in the "PowerUp NACK Delta" parameter. The repetition occurs up to the specified number in "PowerUp NACK Repeat" before a new one Connection establishment with preamble and initialized service happens (see 1 ). Also when the default value 0 is received, the transmission power is increased the next time it is repeated. With a certain number of ACKs (hysteresis), indicated by the "PowerDown Threshold" parameter, the power for the next data packet can be reduced.

In 2 the frame structure for the PRACH message part is shown. The "radio frame" of the message part comprises a time of 10 ms, which is designated TRACH in the figure. This radio frame is divided into 15 time slots S # 0 to S # 14. Each time slot contains a data part D and a control part or control part C. The control part is in turn divided into a pilot section and a transport format combination indicator section.

Only specific control information of the physical layer is read on the control part det, such as so-called "pilot bits" for channel estimation and "TFCI bits" as a transport format combination indicator for the data part. The actual message is sent from the RACH transport channel on the data part. The number of data bits transmitted on the control and data part per frame or time slot NPilot, NTFCI, NData results from the spreading factor (SF) of the OVSF spreading code used (OVSF Orthogonal Variable Spreading Factor) and the modulation type BPSK used in the uplink (Binary Phase Shift Keying). The control part is always spread with a spreading code with a spreading factor of 256, so that 10 bits are transmitted in a time slot with a length of 2560 chips. Spreading codes with a spreading factor of 32, 64, 128 or 256 are possible for the data part. This means that at least 10 bits with a spreading factor of 256 to a maximum of 80 bits with a spreading factor of 32 can be transmitted per time slot with a length of 2560 chips.

The various configurations and embodiments of the invention enable thus an efficient uplink data transmission for jerky Packet data applications in UMTS FDD mode using the for performance adjustment via the HS-S-CCPCH improved PRACHs.

2.3 Detailed embodiments

• – In einer UMTS-Zelle stehen sowohl PRACHs und HS-PRACHs bzw. S-CCPCHs und HS-SCCPCHs zur effizienteren Datenübertragung im Uplink zur Verfügung.
• – Es wird ein Terminal UE im "Connected" Mode betrachtet, das auf dem HS-PRACH eine Präambel sendet und auf dem AICH ein ACK empfängt.
• – Für den HS-PRACH wurden die neuen Parameter im ASC wie folgt konfiguriert: – PowerUp NACK Delta (PND) = 3 – PowerUp NACK Repeat (PNR) = 3 – PowerUp Treshold (PUT) = 2 – PowerDown Delta (PDD) = 3 – PowerDown Treshold (PDT) = 2

The following assumptions apply to the following two exemplary embodiments:

• - In a UMTS cell, both PRACHs and HS-PRACHs or S-CCPCHs and HS-SCCPCHs are available for more efficient data transmission in the uplink.
• - A terminal UE in "Connected" mode is considered, which sends a preamble on the HS-PRACH and receives an ACK on the AICH.
• - For the HS-PRACH, the new parameters in the ASC were configured as follows: - PowerUp NACK Delta (PND) = 3 - PowerUp NACK Repeat (PNR) = 3 - PowerUp Treshold (PUT) = 2 - PowerDown Delta (PDD) = 3 - PowerDown Threshold (PDT) = 2

Embodiment 1: increase in transmission power Random Access transmission

In 4 the process of an increase in performance in the case of a random access transmission in UMTS FDD mode can be seen. The transmission power SP is plotted against the time above, specifically for the base station for the channels HS-S-CCPCH and AICH, for the terminal for the extended HS-PRACH.

The Base station BS uses the AICH only as a return channel for that sent by the terminal UE Preamble, while the base station BS uses the HS-S-CCPCH only as a return channel for the transmitted HS-PRACH.

After receiving a NACK several times, for example twice, the UE terminal sends the HS-PRACH message part HS-PRACH NT with increased transmission power. In 4 is shown how the terminal UE sends the HS-PRACH message part HS-PRACH NT several times and increases the transmission power after receiving a NACK twice from the base station BS.

The first embodiment is in 4 illustrated graphically. The UE terminal sends a preamble on the HS-PRACH using the ALOHA procedure with an initial power setting. The HS-PRACH is an additional channel used for the rantom access data transmission for uplink data transmission based on a new subframe structure in order to minimize interference in the cell in the uplink. It is based on that in the 2 and 3 shown specification of the PRACH, which has improved transmission properties.

In this example it is assumed that UTRAN sends an acknowledgment through an ACK on the AICH at the defined time of τ _{p – a} = 1.5 access time slots. Thus, the terminal UE can send the actual data on the HS-PRACH at the defined time of τ _p-m = 3 access time slots. The first data segment 1 is sent with a power derived from the power setting used in the preamble. In this example it is assumed that UTRAN confirms that this data has been received by a NACK on the HS-S-CCPCH. The first data segment 1 is therefore repeated. No change is made in the power setting, since the "PowerUp Threshold" is set to two and therefore the transmission power is not changed until the second iteration. The repeated segment is also negatively confirmed by the UTRAN by a NACK on the HS-S-CCPCH. Now with the second one Repetition of a power change according to the value "PowerUp Delta" PND by + 3dBm. The same procedure would also take place when the standard value 0 was received.

In this example would the terminal UE up to a maximum of three repetitions of the same Data segment with increased Send power because the parameter "PowerUp Repeat" PUR is set to three here and the threshold value "PowerUp Treshold "PUT already is reached. The state of the art for PRACH defined maximum power is not exceeded.

The further course of the embodiment is no longer part of the 4 , It is assumed that UTRAN now confirms receipt of the second repetition of the data segment by an ACK on the HS-S-CCPCH. The next data segment can be sent with the same power setting. The process of a later reduction in the transmission power is illustrated in the second exemplary embodiment.

Embodiment 2: transmission power reduction with random access transmission

The second embodiment is in 5 represented graphically. As in 4 here too the transmission power SP is plotted against time, HS-S-CCPCH and AICH are again listed for the base station BS and HS-PRACH for the UE terminal.

Again Terminal UE sends a preamble according to the ALOHA procedure the HS-PRACH with an initial power setting. In this Example is also assumed that UTRAN by an ACK sends the AICH a confirmation at the defined time. The initialization process does not deviate from the standard, so the case of an unsuccessful Sending the preamble not considered further here must become. As in the first example, the UE terminal can do the actual Send data on the HS-PRACH. In this example, suppose that UTRAN, the error-free reception of the first data segment 1 confirmed by an ACK on the HS-S-CCPCH.

The Length of time it takes to send the HS-PRACH message part, is labeled HS-PRACH TTI.

The second data segment 2 is sent by the terminal UE. Doing so no change made in the power setting, since the "PowerDown Threshold" PDT is set to two and thus a change only after two successively confirmed segments the transmission power takes place in the third segment. The reception too of the second segment is from UTRAN through an ACK on the HS-S-CCPCH approved. Now, when the third data segment 3 is sent, there is a change in performance after the value "PowerDown Delta "PDD by -3dBm. The next The transmission power is not reduced immediately the following confirmed Data segment 4, but only after reaching the "PowerDown Threshold" PDT again. Is conceivable to introduce a minimum transmission power that did not fall below should continue.

Also when the present invention is particularly based on examples was described from UMTS, so it is also a variety of different Communication systems and channels to apply in them. Also serve as an indication of the range of use the terminology under number 1.

Abbreviations

• ACK Acknowledgment
• AICH Acquisition Indicator Channel
• ASC Access Service Class
• BCH broadcast channel
• CCCH Common Control Channel
• CPICH Common Pilot Channel
• DCCH Dedicated Control Channel
• DL downlink
• DPDCH Dedicated Physical Data Channel
• FBI feedback information
• FDD Frequency Division Duplex
• HS-PRACH High Speed PRACH
• HS-S-CCPCH High Speed S-CCPCH
• kbps kilo bits per second
• Mbps Mega bits per second
• Mcps mega chips per second
• NACK Negative Acknowledgment
• PRACH Physical Random Access Channel
• QoS Quality of Service
• S-CCPCH Secondary Common Control Physical Channel
• SF spreading factor
• TDD Time Division Duplex
• TFCI Transport Format Combination Indicator
• TFL transmission frame length
• TFS Transport Format Set
• TM Transparent Mode
• TPC Transmit Power Control
• TST Transmission Start Time
• TSTP Transmission Start Time Probability
• TTI transmission time interval
• TX Transmit
• UE user equipment
• UMTS Universal Mobile Telecommunications System
• UTRAN UMTS Terrestrial Radio Access Network

Claims (5)

Method of transferring data on a common radio channel, each between a base station (BS) and a plurality of terminals (UE) in a communication system is provided as a common random access channel (HS-PRACH) where - a terminal (UE) after a positive request, data on the common Random access channel to be allowed to send data over the common random access channel (HS-PRACH) to the base station (BS) sends, - the Base station (BS) a positive or negative confirmation of the correct receipt or incorrect receipt of this data via a common control channel (HS-S-CCPCH) to the terminal (UE) - and the Terminal (UE) depending of whether the confirmation is positive or negative, the transmission power and the transmission process adjusted by the following parameters: a) a first performance increase parameter (PND), which specifies a value by which the power is increased if there is a negative confirmation (NACK) is received b) a first repeat parameter (PNR), which indicates the number of times the request with increased performance is sent if a negative acknowledgment (NACK) is received; c) a performance increase threshold parameter (PUT), about which is the successive number of negative affirmations (NACK) is set, after receiving the transmission power is increased; d) a power reduction parameter (PDD), which indicates the value, a service in case of receipt of a positive confirmation (ACK) is lowered; e) a power reduction threshold parameter (PDT), which is the successive number of positive acknowledgments (ACK) defines, after receiving the performance is reduced. The method of claim 1, wherein the Communication system around a according to the UMTS standard, especially in the FDD mode, working communication system is. Terminal (UE) with a transmitter / receiver unit and a processor unit which is used to control the power of the transmission power cooperate such that a method according to claim 1 or 2 feasible is. Base station (BS) with a transmitter / receiver unit and a processor unit, which regulates the power of the transmission power cooperate such that a method according to claim 1 or 2 is feasible. Communication system comprising a terminal (UE) according to claim 3 and a base station (BS) according to claim 4.