# Patent

## Title
Transmitting method, receiving method, radio base station, and mobile station

## Abstract

A transmission method according to the present invention includes: concatenating CRC masking data and receiver identification information for identifying the receiver; generating CRC check bits by performing a CRC encoding processing against non-CRC masking data; masking the CRC check bits by the concatenated receiver identification information and CRC masking data; concatenating the masking result and the non-CRC masking data; generating a transmission signal by performing an FEC encoding processing against the concatenated masking result and the non-CRC masking data, which are added; and transmitting the transmission signal to the receiver.

## Background
TECHNICAL FIELD
The present invention relates to a transmission method for transmitting transmission data including CRC masking data and non-CRC masking data, a reception method for receiving the transmission data, a radio base station performing a transmission processing by the transmission method, and a mobile station performing a reception processing by the reception method.
BACKGROUND ART
In a conventional mobile communication system, in an uplink from a mobile station UE to a radio base station Node B, a radio network controller RNC is configured to determine a transmission rate of a dedicated channel, in consideration of radio resources of the radio base station Node B, an interference volume in an uplink, a transmission power of the mobile station UE, a transmission processing performance of the mobile station UE, a transmission rate required for an upper application, and the like, and to notify the determined transmission rate of the dedicated channel by a message in a layer-3 (Radio Resource Control Layer) to both of the mobile station UE and the radio base station Node B.
Here, the radio network controller RNC is provided at an upper level of the radio base station Node B, and is an apparatus configured to control the radio base station Node B and the mobile station UE.
In general, data communications often cause burst traffic compared with voice communications or TV communications. Therefore, it is preferable that the transmission rate of a channel used for the data communications is changed fast.
However, as shown in FIG. 11, the radio network controller RNC integrally controls a plurality of radio base stations Node B in general. Therefore, in the conventional mobile communication system, there has been a problem that it is difficult to perform fast control for changing the transmission rate of channel (for example, per approximately 1 through 100 ms), due to processing load, processing delay, or the like.
In addition, in the conventional mobile communication system, there has also been a problem that costs for implementing an apparatus and for operating a network are substantially increased even if the fast control for changing of the transmission rate of the channel can be performed.
Therefore, in the conventional mobile communication system, control for changing the transmission rate of the channel is generally performed on the order from a few hundred ms to a few seconds.
Accordingly, in the conventional mobile communication system, when burst data transmission is performed as shown in FIG. 12(a), the data are transmitted by accepting low-speed, high-delay, and low-transmission efficiency as shown in FIG. 12(b), or, as shown in FIG. 12(c), by reserving radio resources for high-speed communications to accept that radio bandwidth resources in an unoccupied state and hardware resources in the radio base station Node B are wasted.
It should be noted that both of the above-described radio bandwidth resources and hardware resources are applied to the vertical radio resources in FIG. 12.
Therefore, the 3rd Generation Partnership Project (3GPP) and the 3rd Generation Partnership Project 2 (3GPP2), which are international standardization organizations of the third generation mobile communication system, have discussed a method for controlling radio resources at high speed in a layer-1 and a media access control (MAC) sub-layer (a layer-2) between the radio base station Node B and the mobile station UE, so as to utilize the radio resources effectively. Such discussions or discussed functions will be hereinafter referred to as “Enhanced Uplink (EUL)”.
In the EUL, a channel for transmitting a transmission power ratio between an Enhanced Dedicated Physical Data Channel (E-DPDCH) and a Dedicated Physical Control Channel (DPCCH) from a radio base station to each mobile station (i.e., an absolute rate control channel (E-AGCH: EDCH-Absolute Grant Channel)) is defined. (e.g., refer to non-patent document 1)
In addition to the above-described transmission power ratio, the E-AGCH is granted with a signal process flag. The signal process flag distinguishes between methods in which the E-AGCH is applicable by each HARQ (Hybrid Automatic Repeat Request) processes respectively, and methods in which the E-AGCH is applicable for all of the HARQ processes. (e.g., refer to non-patent document 2)
In this regard, on the E-AGCH, the radio base station masks 16-bit CRC check bits by the identifier for the destination mobile station (E-RNTI: Enhanced-Radio Network Temporary Indicator) and adds the masked result to information bits (transmission data). Then, the destination mobile station (mobile station identified by the E-RNTI) performs a CRC error detection processing by performing an FEC decoding against the E-AGCH and unmasking extracted CRC sequence by own E-RNTI. Thus, the destination mobile station enables to detect the status that the signals transmitted to the own station are received correctly.
However, since an impact in the downlink due to the transmission of the E-AGCH is large, there has been a problem that the radio base station cannot transmit transmission data larger than limited number of bits (data size).
Accordingly, it is recommended that the transmission data (information bits) to be mapped to the E-AGCH is determined as 9 to 10 bits at most, thereby the transmission power ratio is controlled.
However, in addition to the above-described transmission power ratio and the signal process flag, information such as a priority level, a soft handover flag for distinguishing between a soft handover user and a non-soft handover user, an effective period of the E-AGCH, or the like can be considered as the transmission data to be mapped to the E-AGCH. Mapping such a large amount of information causes larger impact on the downlink.
In addition, the E-RNTI consists of 16 bits, which is possible to take 65536 values. However, there has been a problem that 16 bits (i.e. 65536 values) is excessive as the number of identifiers of the mobile station to be assigned to the user in the cell.
(Non-patent Document 1) 3GPP TSG-RAN TS25.211 v6.4.0
(Non-patent Document 2) 3GPP TSG-RAN TS25.309 v6.2.0
(Non-patent Document 3) 3GPP R1-05-0219
DISCLOSURE OF THE INVENTION
The present invention has been made considering the above-described problems, and its object is to provide a transmission method, a reception method, a radio base station and a mobile station that makes it possible to prevent decrease of a radio capacity in a downlink by reducing transmission data size to be transmitted in the downlink and thereby limiting a transmission power ratio.
A first aspect of the present invention is summarized as a transmission method for transmitting, to a receiver, transmission data including CRC masking data and non-CRC masking data, including: concatenating the CRC masking data and the receiver identification information for identifying the receiver; generating CRC check bits by performing a CRC encoding processing against non-CRC masking data; masking the CRC check bits by the concatenated receiver identification information and CRC masking data; concatenating the masking result and the non-CRC masking data; generating a transmission signal by performing an FEC encoding processing against the concatenated masking result and non-CRC masking data; and transmitting the transmission signal to the receiver.
In the first aspect of the present invention, the CRC masking data may include at least one of a priority class for the transmission data, a process flag for an HARQ, an effective period, a data size, a soft handover flag, and logical channel identification information.
A second aspect of the present invention is summarized as a reception method for receiving a signal received from a transmitter, including: extracting a CRC sequence and a non-CRC masking data sequence by performing an FEC decoding processing against the signal received from the transmitter; preparing a plurality of data sequence, each of the plurality of data sequence including a predetermined bit pattern and receiver identification information for identifying a receiver; extracting CRC check bits by unmasking the CRC sequence by each of the plurality of data sequence; detecting presence or absence of an error of non-CRC masking data by using the extracted CRC check bits; and re-generating transmission data including the non-CRC masking data and the CRC sequence, based on the detection result.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a functional block diagram of a mobile station of a mobile communication system according to a first embodiment of the present invention.
FIG. 2 is a functional block diagram of a baseband signal processing section in the mobile station of the mobile communication system according to the first embodiment of the invention.
FIG. 3 is a functional block diagram of a MAC-e processing section of the baseband signal processing section in the mobile station of the mobile communication system according to the first embodiment of the present invention.
FIG. 4 is a functional block diagram of a radio base station of the mobile communication system according to the first embodiment of the present invention.
FIG. 5 is a functional block diagram of the baseband signal processing section in a radio base station of the mobile communication system according to the first embodiment of the present invention.
FIG. 6 is a functional block diagram of a MAC-e and Layer 1 processing section (configuration for uplink), of the baseband signal processing section in the radio base station of the mobile communication system according to the first embodiment of the invention.
FIG. 7 is a functional block diagram of a MAC-e functional section of the MAC-e and layer-1 processing section (configuration for uplink), of the baseband signal processing section in a radio base station of the mobile communication system according to the first embodiment of the present invention.
FIG. 8 is a functional block diagram of a radio network controller of the mobile communication system according to the first embodiment of the present invention.
FIG. 9 is a diagram for explaining a transmission processing operation of the mobile communication system according to the first embodiment of the invention.
FIG. 10 is a diagram for explaining a reception processing operation of the mobile communication system according to the first embodiment of the invention.
FIG. 11 is a diagram showing an entire configuration of a general mobile communication system.
FIGS. 12(a) to 12(c) are graphs illustrating operations at a time of burst data transmission in a conventional mobile communication system.



BEST MODE FOR CARRYING OUT THE INVENTION
Mobile Communication System According to First Embodiment of the Present Invention
A description will be given of a configuration of a mobile communication system according to a first embodiment of the present invention with reference to FIGS. 1 to 8. It should be noted that, as shown in FIG. 11, the mobile communication system according to this embodiment is provided with a plurality of radio base stations Node B #1 to Node B #5 and a radio network controller RNC.
In addition, in the mobile communication system according to this embodiment, a “High Speed Downlink Packet Access (HSDPA)” is used in a downlink, and an “Enhanced Uplink (EUL)” is used in an uplink. It should be noted that in both of the HSDPA and the EUL, retransmission control (N process stop and wait) shall be performed by an HARQ”.
Therefore, an Enhanced Dedicated Physical Channel (E-DPCH), configured of an Enhanced Dedicated Physical Data Channel (E-DPDCH) and an Enhanced Dedicated Physical Control Channel (E-DPCCH), and a Dedicated Physical Channel (DPCH), configured of a Dedicated Physical Data Channel (DPDCH) and a Dedicated Physical Control Channel (DPCCH), are used in the uplink.
Here, the E-DPCCH transmits EUL control data such as a transmission format number for defining a transmission format (transmission block size, or the like) of the E-DPDCH, HARQ related information (the number of retransmission, or the like), and scheduling related information (a transmission power, a buffer residence-volume, or the like in the mobile station UE).
In addition, the E-DPDCH is paired with the E-DPCCH, and transmits user data for the mobile station UE based on the EUL control data transmitted through the E-DPCCH.
The DPCCH transmits control data such as a pilot symbol used for RAKE combining, SIR measurement, or the like, a Transport Format Combination Indicator (TFCI) for identifying a transmission format of the uplink DPDCH, and control data such as transmission power control bits in a downlink, or the like.
In addition, the DPDCH is paired with the DPCCH, and transmits user data for the mobile station UE based on the control data transmitted through the DPCCH. However, if user data to be transmitted does not exist in the mobile station UE, the DPDCH can be configured not to be transmitted.
In addition, in the uplink, a “High Speed Dedicated Physical Control Channel (HS-DPCCH)”, which is required when the HSPDA is applied, is also used.
The HS-DPCCH transmits a Channel Quality Indicator (CQI), and a transmission acknowledgement signal (Ack or Nack) for the HS-DPCCH.
As shown in FIG. 1, the mobile station UE according to this embodiment is provided with a bus interface 31, a call processing section 32, a baseband processing section 33, a radio frequency (RF) section 34, and a transmission-reception antenna 35.
These functions can be independently present as hardware, and can be partly or entirely integrated, or can be configured through a process of software.
The bus interface 31 is configured to forward user data output from the call processing section 32 to another functional section (for example, an application related functional section). In addition, the bus interface 31 is configured to forward user data transmitted from another functional section (for example, the application related functional section) to the call processing section 32.
The call processing section 32 is configured to perform a call control processing for transmitting and receiving user data.
The baseband signal processing section 33 is configured to transmit user data to the call processing section 32, the user data acquired by performing a layer-1 processing including a despreading processing, a RAKE combining processing, and an FEC (Forward Error Correction) decoding processing, a MAC (Media Access Control) processing including a MAC-e processing and a MAC-d processing, and a “Radio Link Control (RLC)” processing, against the baseband signals transmitted from the RF section 34.
In addition, the baseband signal processing section 33 is configured to generate the baseband signals by performing the RLC processing, the MAC processing, or the layer-1 processing against the user data transmitted from the call processing section 32 so as to transmit the baseband signals to the RF section 34.
Detailed description of the functions of the baseband signal processing section 33 will be given later.
The RF section 34 is configured to generate baseband signals by performing the detection processing, the filtering processing, the quantization processing, or the like against radio frequency signals received through the transmission-reception antenna 35, so as to transmit the generated baseband signals to the baseband signal processing section 33.
In addition, the RF section 34 is configured to convert the baseband signals transmitted from the baseband signal processing section 33 into the radio frequency signals.
As shown in FIG. 2, the baseband signal processing section 33 is provided with an RLC processing section 33a, a MAC-d processing section 33b, a MAC-e processing section 33c, and a layer-1 processing section 33d. 
The RLC processing section 33a is configured to perform a processing (RLC processing) in an upper layer of a layer-2, against the user transmitted from the call processing section 32, and to transmit the user data to the MAC-d processing section 33b, 
The MAC-d processing section 33b is configured to grant a channel identifier header and to generate a transmission format in the uplink based on the transmission power limit in the uplink.
As shown in FIG. 3, the MAC-e processing section 33c is provided with an Enhanced Transport Format Combination (E-TFC) selecting section 33c1 and an HARQ processing section 33c2.
The E-TFC selecting section 33c1 is configured to determine a transmission format (E-TFC) of the E-DPDCH based on scheduling signals (such as the E-AGCH, the E-RGCH, or the like) transmitted from the radio base station Node B.
In addition, the E-TFC selecting section 33c1 is configured to transmit transmission format information on the determined transmission format (that is, a transmission data block size, a transmission power ratio between the E-DPDCH and the DPCCH, or the like) to the layer-1 processing section 33d, as well as to transmit the determined transmission format information to the HARQ processing section 33c2.
Such scheduling signals are information notified in the cell where the mobile station UE is located, and include control information for all the mobile stations located in the cell, or a specific group of the mobile stations located in the cell.
The HARQ processing section 33c2 is configured to perform process control for the “stop-and-wait of N-process”, and to transmit the user data in the uplink based on the transmission acknowledgement signal (Ack/Nack for uplink data) transmitted from the radio base station Node B.
Specifically, the HARQ processing section 33c2 is configured to determine whether or not reception processing of the downlink user data was successful, based on the result of the “Cyclic Redundancy Check (CRC)” entered from the layer-1 processing section 33d. 
Then, the HARQ processing section 33c2 is configured to generate a transmission acknowledgement signal (Ack/Nack for the downlink user data) based on the determined result, so as to transmit the acknowledgement signal to the layer-1 processing section 33d. 
In addition, when the above-described determination result was “OK”, the HARQ processing section 33c2 transmits the downlink user data entered from the layer-1 processing section 33d, to the MAC-d processing section 33d. 
As shown in FIG. 4, the radio base station Node B according to this embodiment is provided with an HWY interface 11, a baseband signal processing section 12, a call control section 13, at least one transmitter-receiver section 14, at least one amplifier section 15, and at least one transmission-reception antenna 16.
The HWY interface 11 is an interface with a radio network controller RNC. Specifically, the HWY interface 11 is configured to receive user data transmitted from the radio network controller RNC to a mobile station UE via a downlink, so as to enter the user data to the baseband signal processing section 12.
In addition, the HWY interface 11 is configured to receive control data for the radio base station Node B from the radio network controller RNC, so as to enter the received control data to the call control section 13.
In addition, the HWY interface 11 is configured to acquire the user data from the baseband signal processing section 12, the user data included in the uplink signals received from a mobile station UE via an uplink, so as to transmit the acquired user data to the radio network controller RNC.
Further, the HWY interface 11 is configured to acquire the control data for the radio network controller RNC from the call control section 13, so as to transmit the acquired control data to the radio network controller RNC.
The baseband signal processing section 12 is configured to generate baseband signals by performing the MAC-e processing or the layer-1 processing against the user data acquired from the HWY interface 11, so as to forward the generated baseband signals to the transmitter-receiver section 14.
Here, the MAC-e processing in the downlink includes an HARQ processing, a scheduling processing, a transmission rate control processing, or the like. In addition, the layer-1 processing in the downlink includes a channel encoding processing of user data, a spreading processing, or the like.
In addition, the baseband signal processing section 12 is configured to extract user data by performing the layer-1 processing or the MAC-e processing against the baseband signals acquired from the transmitter-receiver section 14, so as to forward the extracted user data to the HWY interface 11.
Here, the MAC-e processing in the uplink includes the HARQ processing, the scheduling processing, the transmission rate control processing, a header disposal processing, or the like. In addition, the layer-1 processing in the uplink includes a despreading processing, a RAKE combining processing, an error correction decoding processing, or the like.
Detailed description of the functions of the baseband signal processing section 12 will be given later.
In addition, the call control section 13 is configured to perform the call control processing based on the control data acquired from the HWY interface 11.
The transmitter-receiver section 14 is configured to perform processing of converting baseband signals into radio frequency signals (downlink signals), the radio frequency signals acquired from the baseband signal processing section 12, so as to transmit the converted radio frequency signals to the amplifier section 15.
In addition, the transmitter-receiver 14 is configured to perform processing of converting the radio frequency signals (uplink signals) into the baseband signals, the radio frequency signals acquired from the amplifier section 15, so as to transmit the converted baseband signals to the baseband signal processing section 12.
The amplifier section 15 is configured to amplify the downlink signals acquired from the transmitter-receiver section 14, so as to transmit the amplified downlink signals to the mobile station UE via the transmission-reception antenna 16. In addition, the amplifier 15 is configured to amplify the uplink signals received by the transmission-reception antenna 16, so as to transmit the amplified uplink signals to the transmitter-receiver section 14.
As shown in FIG. 5, the baseband signal processing section 12 is provided with a MAC-e and layer-1 processing section 123.
The MAC-e and layer-1 processing section 123 is configured to perform the despreading processing, a RAKE combining processing, an error correction decoding processing, an HARQ processing, or the like, against the baseband signals acquired from the transmitter-receiver section 14. However, these functions are not clearly divided per hardware, and can be acquired by software.
As shown in FIG. 6, the MAC-e and layer-1 processing section (configuration for the uplink) 123 is provided with a DPCCH RAKE section 123a, a DPDCH RAKE section 123b, an E-DPCCH RAKE section 123c, an E-DPDCH RAKE section 123d, an HS-DPCCH RAKE section 123e, a TFCI decoder section 123g, buffers 123h and 123m, re-despreading sections 123i and 123n, FEC decoder sections 123j and 123p, an E-DPCCH decoder section 123k, a MAC-e functional section 123l, an HARQ buffer 123o, a MAC-hs functional section 123q. 
The E-DPCCH RAKE section 123c is configured to perform, against the E-DPCCH in the baseband signals transmitted from the transmitter-receiver section 14, a despreading processing and a RAKE combining processing using a pilot symbol included in the DPCCH.
The E-DPCCH decoder section 123k is configured to acquire transmission format number related information, HARQ related information, scheduling related information, or the like, by performing the decoding processing against the RAKE combining outputs of the E-DPCCH RAKE section 123c, so as to enter the acquired information to the MAC-e functional section 123l. 
The E-DPDCH RAKE section 123d is configured to perform, against the E-DPDCH in the baseband signals transmitted from the transmitter-receiver section 14, a despreading processing using the transmission format information (the number of codes) transmitted from the MAC-e functional section 123l and the RAKE combining processing using the pilot symbol included in the DPCCH.
The buffer 123m is configured to store the RAKE combining outputs of the E-DPDCH RAKE section 123d based on the transmission format information (the number of symbols) transmitted from the MAC-e functional section 123l. 
The re-despreading section 123n is configured to perform a despreading processing against the RAKE combining outputs of the E-DPDCH RAKE section 123d stored in the buffer 123m, based on the transmission format information (spreading factor) transmitted from the MAC-e functional section 123l. 
The HARQ buffer 123o is configured to store the despreading processing outputs of the re-despreading section 123n, based on the transmission format information transmitted from the MAC-e functional section 123l. 
The FEC decoder section 123p is configured to perform an error correction decoding processing (the FEC decoding processing) against the despreading processing outputs of the re-despreading section 123n stored in the HARQ buffer 123o, based on the transmission format information (the transmission data block size) transmitted from the MAC-e functional section 123l. 
The MAC-e functional section 123l is configured to calculate and output the transmission format information (the number of codes, the number of symbols, the spreading factor, the transmission data block size, and the like) based on the transmission format number related information, the HARQ related information, the scheduling related information, and the like, which are acquired from the E-DPCCH decoder section 123k. 
In addition, as shown in FIG. 7, the MAC-e functional section 123l1 is provided with a receive processing command section 123l1, an HARQ processing section 123l2, and a scheduling section 123l3.
The receive processing command section 123l1 is configured to transmit the transmission format number related information, the HARQ related information, and the scheduling related information, which are entered from the E-DPCCH decoder section 123k, to the HARQ processing section 123l2.
In addition, the receive processing command section 123l1 is configured to transmit the scheduling related information entered from the E-DPCCH decoder 123k, to the scheduling section 123l3.
Further, the receive processing command section 123l1 is configured to output the transmission format information corresponding to the transmission format number entered from the E-DPCCH decoder section 123k. 
The HARQ control section 123l2 is configured to determine whether or not the reception processing of uplink user data has been successful, based on the CRC result entered from the FEC decoder section 123p. 
Then, the HARQ control section 123l2 is configured to generate a transmission acknowledgement signal (Ack or Nack) based on the determination result, so as to transmit the generated acknowledgement signal to the configuration for the downlink of the baseband signal processing section 12.
In addition, the HARQ control section 123l2 is configured to transmit the uplink user data entered from the FEC decoder section 123p to the radio network controller RNC, when the above determination result has been “OK”.
In addition, when the above determination result is “OK”, the HARQ control section 123l2 is configured to clear soft decision information stored in the HARQ buffer 123o. 
On the other hand, the HARQ control section 123l2 is configured to store the uplink user data in the HARQ buffer 123o, when the above determination result is “NG”.
In addition, the HARQ control section 123l2 is configured to forward the above determination result to the receive processing command section 123l1. The receive processing control command section 123l1 is configured to notify the E-DPDCH RAKE section 123d and the buffer 123m, of a hardware resource to be prepared for the following transmission time interval (TTI), so as to perform notification for reserving the resource in the HARQ buffer 123o. 
In addition, when the uplink user data is stored in the buffer 123m per TTI, the receive processing command section 123l1 is configured to instruct the HARQ buffer 123o and the FEC decoder section 123p to perform the FEC decoding processing after adding the newly received uplink user data and the uplink user data, which is stored in the HARQ buffer 123o, in a process corresponding to the TTI.
The scheduling section 123l3 is configured to transmit scheduling signals (such as the E-AGCH, an Relative Rate Control Channel (E-DCH Relative Grant Channel: E-RGCH), or the like) through the configuration for the uplink.
The radio network controller RNC according to the present embodiment is an apparatus located on upper level of the radio base station Node B and configured to control radio communication between the radio base station Node B and the mobile station UE.
As shown in FIG. 8, the radio network controller RNC according to this embodiment is provided with an exchange interface 51, a Radio Link Control (RLC) layer processing section 52, an MAC layer processing section 53, a media signal processing section 54, a radio base station interface 55, and a call control section 56.
The exchange interface 51 is an interface with an exchange 1. The exchange interface 51 is configured to forward the downlink signals transmitted from the exchange 1 to the RLC layer processing section 52, and to forward the uplink signals transmitted from the RLC layer processing section 52 to the exchange 1.
The RLC layer processing section 52 is configured to perform an RLC (Radio Link Control) sub-layer processing such as a synthesis processing of a header (e.g. a sequence number), a trailer, or the like.
The RLC layer processing section 52 is also configured to transmit the uplink signals to the exchange interface 51 and to transmit the downlink signals to the MAC layer processing section 53, after the RLC sub-layer processing is performed.
The MAC layer processing section 53 is configured to perform an MAC layer processing such as a priority control processing, a header granting processing, or the like.
The MAC layer processing section 53 is also configured to transmit the uplink signals to the RLC layer processing section 52 and to transmit the downlink signals to the radio base station interface 55 (or a media signal processing section 54), after the MAC layer processing is performed.
The media signal processing section 54 is configured to perform a media signal processing against voice signals or real time image signals.
The media signal processing section 54 is also configured to transmit the uplink signals to the MAC layer processing section 53 and to transmit the downlink signals to the radio base station interface 55, after the media signal processing is performed.
The radio base station interface 55 is an interface with the radio base station Node B. The radio base station interface 55 is configured to forward the uplink signals transmitted from the radio base station Node B to the MAC layer processing section 53 (or the media signal processing section 54) and to forward the downlink signals transmitted from the MAC layer processing section 53 (or the media signal processing section 54) to the radio base station Node B.
The call control section 56 is configured to perform a radio resource control processing, a channel setup and an open processing by the layer-3 signaling, or the like. Here, the radio resource control processing includes a call admission control processing, a handover control processing, or the like.
With reference to FIG. 9, an operation of the mobile communication system according to the first embodiment of the present invention will be described. FIG. 9 shows a transmission processing at the radio base station, and FIG. 10 shows a reception processing at the mobile station UE.
As shown in FIG. 9, in step S101, the radio base station Node B generates a data sequence A by concatenating CRC masking data and an E-RNTI (receiver identification information) for identifying a destination mobile station UE (receiver). The data sequence A has the same bit number as CRC check bits (or the number smaller than the CRC check bits).
In step S102, the radio base station Node B generates CRC check bits by performing a CRC encoding processing against non-CRC multiplication data.
In step S103, the radio base station Node B generates a data sequence B by masking the CRC check bits by the data sequence A (the E-RNTI (receiver identification information) and the CRC multiplication data, which are added).
In step S104, the radio base station Node B generates an E-AGCH transmission data sequence by concatenating a data sequence B (the masking result) and non-CRC masking data, i.e. by attaching the data sequence B to the non-CRC masking data.
In step S105, the radio base station Node B generates a transmission signal by performing an FEC encoding processing against the E-AGCH transmission data sequence (the concatenated masking result and non-CRC multiplication data).
In step S106, the radio base station Node B transmits the transmission signal to the mobile station UE (receiver).
It should be noted that the above-described CRC masking data includes at least one of a priority class for the transmission data, a process flag for the HARQ, an effective period, a data size, a soft handover flag, logical channel identification information.
As shown in FIG. 10, in step S201, the mobile station UE extracts a CRC sequence and a non-CRC masking data sequence by performing an FEC decoding processing against signals received from the radio base station Node B (transmitter).
In step S202, the mobiles station UE prepares a plurality of data sequence C, each of the plurality of data sequence C including the E-RNT (receiver identification information) for identifying the mobile station UE, and a predetermined bit pattern (i.e., all possible bit pattern values) (1) to (N).
In step S203, the mobile station UE extracts CRC check bits by unmasking the CRC sequence by each of the plurality of data sequence C.
In step S204, the mobile station UE detects presence or absence of an error of the non-CRC masking data by using the extracted CRC check bits. (i.e., the mobile station UE performs CRC check)
In steps S205 and S206 the mobile station UE re-generates transmission data including the non-CRC masking data and the CRC sequence, based on the detected result.
Specifically, when the CRC check result has been “NG” (NG=No Good, i.e. CRC check result shows failure), the mobile station UE applies different bit patterns to the CRC masking data portion and repeats the same processing until the CRC check result indicates “OK” (i.e. CRC check results shows success).
The mobile station UE receives the CRC masking data and the non-CRC masking data in which the CRC result is “OK”, as a transmission data destined for the own mobile station.
According to the mobile communication system of the present embodiment, the radio base station Node B masks the CRC check bits not only by the E-RNTI, but together with other information element(s), and then performs the FEC encoding processing. Further, the mobile station UE assumes all possible values for the information element and unmasks the CRC check bits, thereby performs the error detection by using the CRC check bits for each of the bit patterns. Thus, transmission with a part of the information element masked on the CRC check bits become possible, thereby transmission bits can be reduced.
Although the present invention has been described in detail above with the embodiment, it is apparent to those skilled in the art that the present invention is not limited to the embodiment described in the present application. The present invention can be implemented as altered and modified embodiments without departing from the spirit and scope of the present invention as defined by the description of claims. Therefore, the description of the present application is for illustrative purposes and is not intended to limit the present invention in any way.
INDUSTRIAL APPLICABILITY
As described above, the present invention can provide a transmission method, a reception method, a radio base station and a mobile station that makes it possible to prevent decrease of a radio capacity in a downlink by reducing the transmission data size to be transmitted in the downlink and thereby controlling a transmission power ratio.

## Claims

1. A transmission method for transmitting, to a receiver, transmission data including CRC masking data and non-CRC masking data, comprising:
concatenating the CRC masking data and the receiver identification information for identifying the receiver;
generating CRC check bits by performing a CRC encoding processing against the non-CRC masking data;
masking the CRC check bits by the concatenated receiver identification information and CRC masking data;
concatenating the masking result and the non-CRC masking data;
generating a transmission signal by performing an FEC encoding processing against the concatenated masking result and non-CRC masking data; and
transmitting the transmission signal to the receiver.

2. The transmission method according to claim 1, wherein the CRC masking data includes at least one of a priority class for the transmission data, a process flag for an HARQ, an effective period, a data size, a soft handover flag, and logical channel identification information.

3. A reception method for receiving a signal received from a transmitter, comprising:
extracting a CRC sequence and a non-CRC masking data sequence by performing an FEC decoding processing against the signal received from the transmitter;
preparing a plurality of data sequence, each of the plurality of data sequence including a predetermined bit pattern and receiver identification information for identifying a receiver;
extracting CRC check bits by unmasking the CRC sequence by each of the plurality of data sequence;
detecting presence or absence of an error of non-CRC masking data by using the extracted CRC check bits; and
re-generating transmission data including the non-CRC masking data and the CRC sequence, based on the detection result.

4. A radio base station which performs a transmission processing by using the transmission method according to claims 1 or 2.

5. A mobile station which performs a reception processing by using the reception method according to claim 3.