JP2006140650A - Mobile communication system, mobile station, and radio base station - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent deterioration in line capacity due to an excessive transmission power offset by decreasing reception errors of an enhanced individual physical data channel (E-DPDCH) due to deterioration in quality of an an enhanced individual physical control channel (E-DPCCH). <P>SOLUTION: A mobile communication system of the present invention is configured to transmit a transmission power reference channel (DPCCH) and a control channel (E-DPCCH) from a mobile station UE to a radio base station NodeB through an up link, and the control channel has a transmission power offset for the transmission power reference channel. The radio base station NodeB is constituted to transmit a delivery confirmation signal of a data channel corresponding to the control channel. The mobile station UE is constituted to control the transmission power offset according to the delivery confirmation signal sent from the radio base station NodeB. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is configured to transmit a transmission power reference channel and a target control channel from a mobile station to a radio base station in the uplink, and the target control channel transmits transmission power for the transmission power reference channel. The present invention relates to a mobile communication system configured to have an offset, and a mobile station and a radio base station used in the mobile communication system.

  In particular, the present invention relates to a technique applicable to a “W-CDMA” type mobile communication system and a “CDMA2000” type mobile communication system, which are third generation mobile communication systems.

  In the conventional mobile communication system, the radio network controller RNC performs radio resource of the radio base station NodeB, amount of interference in the uplink, transmission power of the mobile station UE, transmission processing of the mobile station UE in uplink communication. In view of performance, transmission rate required by the higher-level application, etc., the transmission rate of the individual channel is determined, and each of the mobile station UE and the radio base station NodeB is determined by a layer 3 (Radio Resource Control Layer) message. Thus, the determined transmission rate of the dedicated channel is notified.

  Here, the radio network controller RNC is an apparatus that exists above the radio base station NodeB and controls the radio base station NodeB and the mobile station UE.

  In general, in data communication, traffic often occurs in a burst manner as compared with voice calls and TV calls. Originally, it is desirable to change the transmission speed of a channel used for data communication at a high speed.

  However, as shown in FIG. 12, the radio network controller RNC normally controls all radio base stations NodeB in an integrated manner. Therefore, in the conventional mobile communication system, due to processing load, processing delay, etc. There is a problem that it is difficult to control the change of the transmission speed of a high-speed channel (for example, about 1 to 100 ms).

  In addition, in the conventional mobile communication system, there is a problem that even if the high-speed channel transmission rate change control can be performed, the device mounting cost and the network operation cost are significantly increased.

  For this reason, in a conventional mobile communication system, it is usual to perform channel transmission rate change control in the order of several hundreds ms to several s.

  Therefore, in the conventional mobile communication system, as shown in FIG. 13 (a), when transmitting transmission data blocks in bursts, as shown in FIG. 13 (b), low speed, high delay and low transmission efficiency are allowed. Then, the transmission data block is transmitted or, as shown in FIG. 13C, radio resources for high-speed communication are secured, and the radio resources in the idle time and the hardware resources in the radio base station Node B are The transmission data block is transmitted while allowing it to be wasted.

  In FIGS. 13B and 13C, it is assumed that both the above-described wireless band resource and hardware resource are applied to the wireless resource on the vertical axis.

  Therefore, in order to effectively use radio resources, in “3GPP” and “3GPP2”, which are international standardization organizations of the third generation mobile communication system, the layer 1 and the MAC sublayer between the radio base station NodeB and the mobile station UE ( High-speed radio resource control methods in layer 2) have been studied. Hereinafter, such a study or a function that has been studied will be collectively referred to as an “uplink enhancement (EUL)”.

  In the uplink enhancement, the radio base station NodeB can increase the cell throughput by controlling the transmission rate of the channel used for communication in the uplink at high speed in the lower layers (layer 1 and layer 2).

  Specifically, as shown in FIG. 14, the radio base station NodeB measures “noise rise” of a channel used for uplink communication, and the noise rise of the channel converges to a level close to the maximum allowable noise rise. Thus, the transmission rate of the channel is configured to be sequentially controlled.

  Here, the noise rise is a ratio between interference power in a predetermined channel within a predetermined frequency and noise power within the predetermined frequency (thermal noise power or noise power from outside the mobile communication system). That is, the noise rise is an offset that the reception level in the communication state has with respect to the reception level (noise floor) in the communication state.

  In this specification, a channel to which uplink enhancement is applied is referred to as an “enhanced channel” (for example, a dedicated channel to which uplink enhancement is applied is referred to as an “enhanced dedicated channel”).

  FIG. 15 shows an uplink channel configuration used in a mobile communication system to which uplink enhancement is applied.

  Such a mobile communication system is configured to transmit an enhanced dedicated physical channel (E-DPCH) and a dedicated physical channel (DPCH) in the uplink.

  An enhanced dedicated physical channel (E-DPCH) is configured by an enhanced dedicated physical data channel (E-DPDCH) and an enhanced dedicated physical channel (E-DPCCH). Yes.

  The dedicated physical channel (DPCH) is configured by a dedicated physical data channel (DPDCH: Dedicated Physical Data Channel) and a dedicated physical control channel (DPCCH: Dedicated Physical Control Channel).

  The enhanced dedicated physical control channel (E-DPCCH) is information related to the transmission format (transmission data block size, etc.) of the enhanced dedicated physical data channel (E-DPDCH), information related to HARQ (number of retransmissions, retransmission number, etc.), and information related to scheduling. It is configured to transmit control data for enhanced dedicated physical channel (E-DPCH) such as (transmission power and buffer retention amount in the mobile station UE). The enhanced dedicated physical control channel (E-DPCCH) is configured to be transmitted only when there is user data to be transmitted on the enhanced dedicated physical data channel (E-DPDCH).

  The enhanced dedicated physical data channel (E-DPDCH) corresponds to the enhanced dedicated physical control channel (E-DPCCH) and is transmitted by the enhanced dedicated physical control channel (E-DPCCH). It is configured to transmit user data based on the control data for DPCH). The enhanced dedicated physical data channel (E-DPDCH) is configured to be transmitted only when there is user data to be transmitted.

  The dedicated physical control channel (DPCCH) is configured to transmit control data for dedicated physical control channel (DPCCH) such as a pilot symbol, a transmission format identifier of the dedicated physical channel (DPCH), and a transmission power control bit for downlink. ing. The dedicated physical control channel (DPCCH) is always transmitted.

  The dedicated physical data channel (DPDCH) corresponds to the dedicated physical control channel (DPCCH), and user data based on the dedicated physical control channel (DPCCH) control data transmitted by the dedicated physical control channel (DPCCH). Is configured to send. The dedicated physical data channel (DPDCH) may be configured to be transmitted only when there is user data to be transmitted.

  When uplink enhancement is applied, the radio base station NodeB is configured to perform closed-loop transmission power control based on the SIR of the pilot symbol portion of the dedicated physical control channel (DPCCH).

  That is, in a mobile communication system to which uplink enhancement is applied, the enhanced dedicated physical control channel (E-DPCCH), the enhanced dedicated physical data channel (E-DPDCH), and the dedicated physical data channel (DPDCH) are dedicated physical control. It has a required transmission power offset for the channel (DPCCH), and is configured to perform communication while maintaining the required transmission power offset even when the transmission power of the dedicated physical control channel (DPCCH) fluctuates. Yes.

  In uplink enhancement, hybrid ARQ (Auto Repeat reQuest, hereinafter referred to as HARQ) is applied.

  As shown in FIG. 16, HARQ is a method in which a data reception side device (radio base station NodeB or mobile station UE) sends a delivery confirmation signal (Ack or Nack) to a received transmission data block. To the mobile station UE or the radio base station NodeB).

  Normally, the data transmission side apparatus receives the next transmission data block (for example, the transmission data block only when the transmission confirmation block (Ack) indicating that the transmission data block (for example, transmission data block # 1) has been correctly received). Data block # 2) is transmitted.

  On the other hand, when receiving a delivery confirmation signal (Nack) indicating that the transmission data block has not been correctly received, the data transmission side apparatus transmits the transmission data block again.

  Further, in HARQ, as shown in FIG. 17, soft combining can be performed. With reference to FIG. 17, the operation principle of soft combining will be briefly described.

  In step S101, the data transmitting apparatus transmits a 3-bit transmission data block, and in step S102, the data receiving apparatus performs a decoding process on the received transmission data block. At this time, it is assumed that the data reception side device has detected a reception error (see step S103). Here, the data reception side apparatus stores the 3 bits constituting the transmission data block in which the reception error is detected as a soft decision bit in the memory.

  In step S104, the data transmission side apparatus retransmits the 3-bit transmission data block, and in step S105, the data reception side apparatus configures the received transmission data block with the soft decision bits stored in the memory. Add 3 bits to increase the signal power to noise power ratio. As a result, the data receiving side apparatus successfully receives the transmission data block without detecting a reception error (see step S106).

  Also, in HARQ, the use efficiency of the radio link can be improved by transmitting the transmission data block after the next transmission data block until the delivery confirmation signal is returned. Stop and weight is known as a simple method for that purpose. With reference to FIG. 18, the operation principle of the four-process stop-and-wait will be briefly described.

  As illustrated in FIG. 18, a time lag occurs after the data transmission side device transmits a transmission data block and receives a delivery confirmation signal of the transmission data block. In the example of FIG. 18, such a time lag is not less than 2 times and not more than 3 times the transmission time of the transmission data block, and therefore the timing at which the transmission data block is retransmitted is after three transmission data blocks.

  In this case, as shown in FIG. 18, it can be considered that four HARQs are operating in parallel, and this is called stop and wait of four processes.

In order to determine the number N of HARQ to be operated in parallel according to the transmission time of the transmission data block, the time lag until receiving the delivery confirmation signal, the processing delay in the data transmission side device and the data reception side device, etc., N processes Are called N Process Stop and Wait.
Supervised by Keiji Tachikawa, "W-CDMA mobile communication system", Maruzen Co., Ltd. 3GPP TR25.896 v6.0.0

  However, strictly speaking, the required transmission power offset may differ depending on the propagation environment, the presence or absence of a soft handover (SHO) state, and the like.

  For this reason, in the conventional mobile communication system, the radio network controller RNC notifies a required transmission power offset (E) by notifying a layer 3 signal in accordance with a change in propagation environment, the start or end of soft handover, and the like. -DPDCH power offset, E-DPCCH power offset, and DPDCH power offset).

  FIG. 19 shows a connection form of an enhanced dedicated physical channel in a handover state in a mobile communication system to which uplink enhancement is applied.

  As shown in FIG. 19, the enhanced dedicated physical data channel (E-DPDCH) performs soft handover, but the enhanced dedicated physical control channel (E-DPCCH) is assigned to each of the radio base stations NodeB # 1 and # 2 Terminated with.

  Here, each of the radio base stations Node B # 1 and # 2 is configured to perform transmission power control (TPC) according to the reception quality of the enhanced dedicated physical data channel (E-DPDCH) selected and synthesized by the radio network controller RNC. Therefore, the enhanced dedicated physical control channel (E-DPCCH) terminated at each of the radio base stations NodeB # 1 and # 2 is always in a state where reception power is insufficient.

  Therefore, the conventional mobile communication system to which uplink enhancement is applied has a problem that the E-DPCCH power offset must be larger than a normal value in the handover state.

  Furthermore, since the enhanced dedicated physical control channel (E-DPCCH) applies intermittent transmission that is transmitted only when the enhanced dedicated physical data channel (E-DPDCH) is transmitted, the radio base station NodeB In some cases, the reception quality of the dedicated physical control channel (E-DPCCH) cannot be grasped.

  Therefore, in the mobile communication system to which the conventional uplink enhancement is applied, the enhanced dedicated physical control channel (E-DPCCH) is set to the maximum possible transmission power offset or the handover state is changed. In such a case, there has been a problem that the radio network controller RNC has to adopt one of the methods of changing the E-DPCCH power offset by a layer 3 signal.

  Therefore, the present invention has been made in view of the above points, and reduces the reception error of the enhanced dedicated physical data channel (E-DPDCH) due to the quality degradation of the enhanced dedicated physical control channel (E-DPCCH), and an excessive amount. It is an object of the present invention to provide a mobile communication system, a mobile station, and a radio base station that can prevent deterioration of channel capacity due to a transmission power offset.

  A first feature of the present invention is configured to transmit a transmission power reference channel (DPCCH) and a target control channel (E-DPCCH) from a mobile station to a radio base station in the uplink, A mobile communication system configured such that a target control channel has a transmission power offset with respect to the transmission power reference channel, wherein the radio base station transmits data corresponding to the target control channel to the mobile station The mobile station is configured to transmit a delivery confirmation signal of a channel (E-DPDCH), and the mobile station is configured to control the transmission power offset according to the delivery confirmation signal transmitted from the radio base station. It is a summary.

  In the first aspect of the present invention, the radio base station may be configured to transmit a delivery confirmation signal indicating reception of the data channel and a decoding result only when the radio base station correctly decodes the target control channel. Good.

  In the first aspect of the present invention, the mobile station is configured to maintain or lower the transmission power offset when the mobile station receives the delivery confirmation signal indicating a reception and decoding result of the data channel. The transmission power offset may be increased when the delivery confirmation signal indicating the reception and decoding results of the data channel is not received within a predetermined period.

  In the first aspect of the present invention, the mobile station is configured to increase the transmission power offset based on “(required reception quality of the target control channel) × (predetermined control width)”. , “(1−required reception quality of the target control channel) × (predetermined control width)” may be configured to reduce the transmission power offset.

  In the first aspect of the present invention, the wireless communication system may further include a radio network controller configured to notify the mobile station of at least one of required reception quality of the target control channel and the predetermined control width. Good.

  A second feature of the present invention is configured to transmit a transmission power reference channel and a target control channel from a mobile station to a radio base station in the uplink, and the target control channel includes the transmission power. A mobile station used in a mobile communication system configured to have a transmission power offset with respect to a reference channel, receiving a delivery confirmation signal of a data channel corresponding to the target control channel from the radio base station, The gist is to include a transmission power offset control unit that controls the transmission power offset in accordance with a delivery confirmation signal.

  In the second aspect of the present invention, the transmission power offset control unit is configured to maintain or lower the transmission power offset when receiving the delivery confirmation signal indicating reception and decoding results of the data channel. The transmission power offset may be increased when the delivery confirmation signal indicating the reception and decoding results of the data channel is not received within a predetermined period.

  In the second aspect of the present invention, the transmission power offset control unit is configured to increase the transmission power offset based on “(required reception quality of the target control channel) × (predetermined control width)”. The transmission power offset may be reduced based on “(1−required reception quality of the target control channel) × (predetermined control width)”.

  A third feature of the present invention is configured to transmit a transmission power reference channel and a target control channel from a mobile station to a radio base station in the uplink, and the target control channel includes the transmission power. A radio base station used in a mobile communication system configured to have a transmission power offset with respect to a reference channel, and only when the mobile station correctly decodes the target control channel, the control channel The gist is that it is configured to transmit a delivery confirmation signal indicating the reception and decoding results of the corresponding data channel.

  As described above, according to the present invention, the reception error of the enhanced dedicated physical data channel (E-DPDCH) due to the degradation of the quality of the enhanced dedicated physical control channel (E-DPCCH) is reduced, and the line due to excessive transmission power offset It is possible to provide a mobile communication system, a mobile station, and a radio base station that can prevent capacity degradation.

(Configuration of mobile communication system according to the first embodiment of the present invention)
The configuration of the mobile communication system according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 8 and FIG. As shown in FIG. 12, the mobile communication system according to the present embodiment includes a plurality of mobile stations UE # 1 to # 8, a plurality of radio base stations NodeB # 1 to # 5, and a radio network controller RNC. is doing.

  In the mobile communication system according to the present embodiment, “HSDPA” is used in the downlink, and “EUL (uplink enhancement)” is used in the uplink. It is assumed that retransmission control by HARQ is performed in both “HSDPA” and “EUL”.

  In the uplink, a high-speed dedicated physical control channel (HS-DPCCH) required when HSPDA is applied and a random access channel (RACH) are also used.

  The high-speed dedicated physical control channel (HS-DPCCH) transmits a downlink quality identifier (CQI: CPICH Quality Indicator) and a delivery confirmation signal (Ack or Nack) for a high-speed dedicated physical data channel.

  Therefore, in the mobile communication system according to the present embodiment, in the uplink, the dedicated physical control channel (DPCCH, transmission power reference channel), the dedicated physical data channel (DPDCH) and the radio base station NodeB from the mobile station UE The enhanced dedicated physical control channel (E-DPCCH, target control channel) and the enhanced dedicated physical data channel (E-DPDCH) are transmitted.

  Here, the dedicated physical data channel (DPDCH) has a DPDCH power offset (transmission power offset) with respect to the dedicated physical control channel (DPCCH), and the enhanced dedicated physical control channel (E-DPCCH, target control channel). ) Has an E-DPCCH power offset (transmission power offset) with respect to the dedicated physical control channel (DPCCH), and the enhanced dedicated physical data channel (E-DPDCH) is assigned to the dedicated physical control channel (DPCCH). On the other hand, it has an E-DPDCH power offset (transmission power offset).

  As shown in FIG. 1, the radio base station NodeB according to the present embodiment includes an HWY interface 11, a baseband signal processing unit 12, a call control unit 13, one or a plurality of transmission / reception units 14, and one or A plurality of amplifier units 15 and one or a plurality of transmission / reception antennas 16 are provided.

  The HWY interface 11 is an interface with the radio network controller RNC. Specifically, the HWY interface is configured to receive user data transmitted from the radio network controller RNC to the mobile station UE via the downlink and input the user data to the baseband signal processing unit 13. The HWY interface 11 is configured to receive control data for the radio base station NodeB from the radio network controller RNC and input it to the call controller 13.

  The HWY interface 11 is configured to acquire user data included in an uplink signal received from the mobile station UE via the uplink from the baseband signal processing unit, and transmit the user data to the radio network controller RNC. ing. Further, the HWY interface 11 is configured to acquire control data for the radio network controller RNC from the call controller 13 and transmit it to the radio network controller RNC.

  The baseband signal processing unit 12 is configured to perform a MAC layer process and a layer 1 process on user data acquired from the HWY interface 11 to generate a baseband signal and transfer the baseband signal to the transmission / reception unit 14. .

  Here, the downlink MAC layer processing includes scheduling processing, transmission rate control processing, and the like. Further, the layer 1 processing in the downlink includes channel coding processing and spreading processing of user data.

  The baseband signal processing unit 12 is configured to perform MAC layer processing and layer 1 processing on the baseband acquired from the transmission / reception unit 14, extract user data, and transfer the user data to the HWY interface 11. Yes.

  Here, the MAC layer processing in the uplink includes MAC control processing, header discard processing, and the like. Also, the layer 1 processing in the downlink includes despreading processing, RAKE combining processing, error correction decoding processing, and the like.

  A specific function of the baseband signal processing unit 12 will be described later. The call control unit 13 performs call control processing based on control data acquired from the HWY interface 11.

  The transmission / reception unit 14 is configured to perform a process of converting the baseband signal acquired from the baseband signal processing unit 12 into a radio frequency band signal (downlink signal) and transmit the signal to the amplifier unit 15. In addition, the transmission / reception unit 14 is configured to perform a process of converting a radio frequency band signal (uplink signal) acquired from the amplifier unit 15 into a baseband signal and transmit the signal to the baseband signal processing unit 12.

  The amplifier unit 15 is configured to amplify the downlink signal acquired from the transmission / reception unit 14 and transmit it to the mobile station UE via the transmission / reception antenna 16. The amplifier unit 15 is configured to amplify the uplink signal received by the transmission / reception antenna 16 and transmit the amplified uplink signal to the transmission / reception unit 14.

  As shown in FIG. 2, the baseband signal processing unit 12 includes, as an uplink configuration 12 # 1, a DPCCH RAKE unit 12a, a DPDCH RAKE unit 12b, an E-DPCCH RAKE unit 12c, and an E-DPDCH RAKE unit 12d. HS-DPCCH RAKE unit 12e, RACH processing unit 12f, TFCI decoder unit 12g, buffers 12h and 12m, re-despreading units 12i and 12n, FEC decoder units 12j and 12o, and E-DPCCH decoder unit 12k, a MAC-e function unit 121, and a MAC-hs function unit 12p.

  The E-DPCCH RAKE unit 12c is included in the despreading process and the dedicated physical control channel (DPCCH) for the enhanced dedicated physical control channel (E-DPCCH) in the baseband signal transmitted from the transmitting / receiving unit 14. RAKE combining processing using existing pilot symbols is performed.

  The E-DPCCH decoder unit 12k performs a decoding process on the RAKE composite output of the E-DPCCH RAKE unit 12c, acquires a transmission format number, information on HARQ, information on scheduling, and the like, and obtains a MAC-e function unit 12l. Is configured to input.

  The E-DPDCH RAKE unit 12d performs reverse processing using the number of codes transmitted from the MAC-e functional unit 12l for the enhanced dedicated physical data channel (E-DPDCH) in the baseband signal transmitted from the transmission / reception unit 14. A spreading process and a RAKE combining process using a pilot symbol included in the dedicated physical control channel (DPCCH) are performed.

  The buffer 12m is configured to accumulate the RAKE combined output of the E-DPDCH RAKE unit 12d based on the number of symbols transmitted from the MAC-e function unit 12l.

  Based on the spreading factor transmitted from the MAC-e function unit 121, the re-despreading unit 12n performs despreading processing on the RAKE composite output of the E-DPDCH RAKE unit 12d stored in the buffer 12m. It is configured.

  The FEC decoder unit 12o is configured to perform error correction decoding processing (FEC decoding processing) on the output of the re-despreading unit 12n based on the transmission data block size transmitted from the MAC-e function unit 12l. Yes.

  The MAC-e function unit 12l transmits transmission format information (number of codes, number of symbols, spreading factor, transmission data block size, etc.) based on the transmission format number, HARQ information, scheduling information, etc. acquired from the E-DPCCH decoder unit 12k. ) Is calculated and output.

  Further, as shown in FIG. 3, the MAC-e function unit 12l includes a reception processing unit 12l1, a HARQ processing unit 12l2, and a scheduling unit 12l3.

  The reception processing unit 12l1 is configured to transmit HARQ information input from the E-DPCCH decoder unit 12o and user data input from the FEC decoder unit 12k to the HARQ processing unit 12l2.

  Further, the reception processing unit 12l1 is configured to transmit information related to scheduling input from the E-DPCCH decoder unit 12o to the scheduling unit 12l3.

  Furthermore, the reception processing unit 12l1 is configured to output transmission format information corresponding to the transmission format number input from the E-DPCCH decoder unit 12o.

  The HARQ processing unit 1212 is configured to determine whether or not the enhanced dedicated physical control channel (E-DPCCH) has been correctly decoded by CRC error detection processing or the like.

  Further, the HARQ processing unit 1212 determines whether or not the enhanced dedicated physical control channel (E-DPCCH) and the enhanced dedicated physical data channel (E-DPDCH) are correctly received and decoded by CRC error detection processing or the like. It is configured.

  The HARQ processing unit 1212 generates a delivery confirmation signal (Ack or Nack) indicating the reception and decoding result of the enhanced dedicated physical data channel (E-DPDCH), and the baseband signal processing unit 12 (downlink configuration) 12 # 2 to transmit to.

  In addition, when the reception and decoding result of the enhanced dedicated physical data channel (E-DPDCH) is OK, the HARQ processing unit 1212 transmits the user data transmitted through the enhanced dedicated physical data channel (E-DPDCH) to the radio channel. It is configured to transmit to the control station RNC.

  Here, only when the enhanced dedicated physical control channel (E-DPCCH) is correctly received and decoded, the HARQ processing unit 1212 receives a delivery confirmation signal (E-DPDCH) reception confirmation signal (E-DPDCH). ACK or Nack) is transmitted.

  On the other hand, when the enhanced dedicated physical control channel (E-DPCCH) cannot be correctly received and decoded, the HARQ processing unit 1212 receives an acknowledgment signal (ACK) indicating the reception and decoding result of the enhanced dedicated physical data channel (E-DPDCH). (Nack) is not transmitted.

  For example, if the enhanced dedicated physical control channel (E-DPCCH) cannot be correctly received and decoded, the HARQ processing unit 1212 may be configured not to transmit the delivery confirmation signal itself, or the enhanced dedicated physical data channel Delivery in which “DTX” indicating that the reception and decoding result of the enhanced dedicated physical data channel (E-DPDCH) is not transmitted is set in the bit part for setting Ack or Nack indicating the reception and decoding result of (E-DPDCH) The confirmation signal may be transmitted.

  The scheduling unit 1213 determines whether transmission is possible in each mobile station UE, transmission rate (transmission data block size) in each mobile station, and maximum allowable transmission power (E -Maximum allowable transmission power of DPCCH or E-DPDCH) is determined and transmitted to the baseband signal processing unit 12 (downlink configuration) 12 # 2.

  Note that the scheduling unit 1213 may be configured to determine the transmission data block size based on uplink congestion level, radio quality, and the like. Further, the scheduling unit 1213 may be configured to provide an upper limit for the maximum allowable transmission power depending on the capability of the maximum transmission power of the mobile station.

  As shown in FIG. 4, the mobile station UE according to this embodiment includes a bus interface 31, a call processing unit 32, a baseband processing unit 33, an RF unit 34, and a transmission / reception antenna 36.

  However, such functions may exist independently as hardware, may be partly or wholly integrated, or may be configured by a software process.

  The bus interface 31 is configured to transfer user data output from the call processing unit 32 to another functional unit (for example, a functional unit related to an application). The bus interface 31 is configured to transfer user data transmitted from another function unit (for example, a function unit related to an application) to the call processing unit 32.

  The call processing unit 32 is configured to perform call control processing for transmitting and receiving user data.

  The baseband signal processing unit 33 performs layer 1 processing including despreading processing, RAKE combining processing, and FEC decoding processing, MAC-e processing, and MAC-d processing on the baseband signal transmitted from the RF unit 34. It is configured to transmit the user data acquired by performing the MAC processing including the RLC processing to the call processing unit 32.

  Further, the baseband signal processing unit 33 performs RLC processing, MAC processing, and layer 1 processing on the user data transmitted from the call processing unit 32 to generate a baseband signal and transmit it to the RF unit 34. It is configured.

  A specific function of the baseband signal processing unit 33 will be described later. The RF unit 34 generates a baseband signal by performing detection processing, filtering processing, quantization processing, and the like on the signal in the radio frequency band received via the transmission / reception antenna 35, and sends the baseband signal to the baseband signal processing unit 33. Configured to send. The RF unit 34 is configured to convert the baseband signal transmitted from the baseband signal processing unit 33 into a signal in a radio frequency band.

  As shown in FIG. 5, the baseband signal processing unit 33 includes an RLC processing unit 33a, a MAC-d processing unit 33b, a MAC-e processing unit 33c, and a layer 1 processing unit 33d.

  The RLC processing unit 33a is configured to process the user data transmitted from the call processing unit 32 in an upper layer of layer 2 and transmit the processed data to the MAC-d processing unit 33b.

  The MAC-d processing unit 33b is configured to add a channel identifier header and create an uplink transmission format based on the limit of uplink transmission power.

  As shown in FIG. 7, the MAC-e processing unit 33c includes an E-TFC selection unit 33c1, a HARQ processing unit 33c2, and an E-DPCCH power offset determination unit 33c3.

  The E-TFC selection unit 33c1 determines the retransmission format of the enhanced dedicated physical data channel (E-DPDCH) and the enhanced dedicated physical control channel (E-DPCCH) based on the scheduling signal transmitted from the radio base station NodeB. It is configured.

  The E-TFC selection unit 33c1 transmits an E-TFC (transmission format information) indicating the determined retransmission format to the layer 1 processing unit 33d, and determines the determined transmission data block size (or enhanced dedicated physical data channel ( E-DPDCH) and an enhanced dedicated physical control channel (E-DPCCH) are transmitted to the HARQ processing unit 33c2.

  Here, the scheduling signal may specify the transmission data block size, or specify the transmission power ratio between the enhanced dedicated physical data channel (E-DPDCH) and the enhanced dedicated physical control channel (E-DPCCH). It may be one that performs, or may simply indicate UP / DOWN.

  The HARQ processing unit 33c2 is configured to execute “N process Stop and Wait” and transmit user data based on a delivery confirmation signal received from the radio base station NodeB. ing.

  Further, when the NACK is received and the number of retransmissions of a specific transmission data block (user data) is less than the maximum number of retransmissions, the HARQ processing unit 33c2 performs retransmission for the transmission data block, When Ack is received or when the number of retransmissions of a specific transmission data block reaches the maximum number of retransmissions, the next transmission data block is transmitted.

  The E-DPCCH power offset determination unit 33c3 performs an E-DPCCH power offset (enhanced dedicated physical control channel (E-DPCCH) and dedicated) according to a delivery confirmation signal (Ack / Nack / DTX) transmitted from the radio base station NodeB. The transmission power ratio (transmission power offset) with the physical control channel (DPCCH) is controlled.

  Here, when the E-DPCCH power offset determination unit 33c3 receives a delivery confirmation signal in which “DTX” is set, a reception error of the enhanced dedicated physical control channel (E-DPCCH) occurs in the radio base station NodeB. Therefore, it is assumed that the reception quality of the enhanced dedicated physical control channel (E-DPCCH) does not satisfy the required reception quality (for example, error rate).

  On the other hand, when the E-DPCCH power offset determining unit 33c3 receives the delivery confirmation signal in which “ACK or Nack” is set, the radio base station NodeB has successfully received the enhanced dedicated physical control channel (E-DPCCH). Therefore, it is assumed that the reception quality (for example, error rate) of the enhanced dedicated physical control channel (E-DPCCH) satisfies the required reception quality.

When the reception quality of the enhanced dedicated physical control channel (E-DPCCH) does not satisfy the required reception quality (for example, error rate 1e ⁻³ [dB]), the E-DPCCH power offset determination unit 33c3 The offset is increased by a certain amount (predetermined control width) from the current value.

On the other hand, when the reception quality of the enhanced dedicated physical control channel (E-DPCCH) is excessive (for example, the reception quality of the enhanced dedicated physical control channel (E-DPCCH) is required for the E-DPCCH power offset determination unit 33c3. The quality (for example, when the error rate 1e ⁻³ [dB]) is satisfied) and the E-DPCCH power offset are made lower by a certain amount (predetermined control width) than the current value.

  That is, the E-DPCCH power offset determination unit 33c3 maintains the E-DPCCH power offset when receiving an acknowledgment signal (Ack or Nack) indicating the reception and decoding result of the enhanced dedicated physical data channel (E-DPCCH). When the reception confirmation signal indicating the reception and decoding results of the enhanced dedicated physical data channel (E-DPCCH) is not received within a predetermined period (for example, the reception confirmation signal itself is not received) Or when an acknowledgment signal (DTX) is received), the E-DPCCH power offset is increased.

  Specifically, the E-DPCCH power offset determination unit 33c3 performs the E-DPCCH power offset based on “(enhanced dedicated physical control channel (E-DPCCH) required reception quality) × (predetermined control width)”. And the E-DPCCH power offset is reduced based on “(1 enhanced dedicated physical control channel (E-DPCCH) required reception quality) × (predetermined control width)”. It is configured.

For example, when the required reception quality of the enhanced dedicated physical control channel (E-DPCCH) is “error rate = 1e ⁻³ [dB]” and the predetermined control width is “Δ”, the HARQ processing unit 33c2 confirms the delivery. When a signal (Ack or Nack) is received, the E-DPCCH power offset is increased by “0.999 × Δ [dB]”, and when a delivery confirmation signal (DTX) is received, “0.999 × Δ [ dB] ”to lower the E-DPCCH power offset.

  However, when the E-DPCCH power offset takes a discrete value, the E-DPCCH power offset determination unit 33c3 can round the controlled E-DPCCH power offset to a discrete value.

  The “required reception quality of the enhanced dedicated physical control channel (E-DPCCH)” and the “predetermined control width” may be values specific to the mobile communication system or are indicated by the radio network controller RNC. It may be a value.

  The E-DPCCH power offset determination unit 33c3 is configured to notify the layer 1 processing unit 33d of a change in the E-DPCCH power offset using the E-DPCCH power offset information.

  As a result, the RF unit 34 controls the transmission power of the enhanced dedicated physical control channel (E-DPCCH) based on the E-DPCCH power offset information transmitted from the HARQ processing unit 33c2.

  As illustrated in FIG. 7, the layer 1 processing unit 33d includes a DPCCH RAKE unit 33d1, a DPDCH RAKE unit 33d2, an RGCH RAKE unit 33d4, a spreading unit 33d6, an FEC encoding unit 33d7, and FEC decoder units 33d3 and 33d5. And a channel power setting unit 33d8.

  The DPDCH RAKE unit 33d2 is configured to perform despreading processing and RAKE combining processing on the dedicated physical data channel DPDCH in the downlink signal transmitted from the RF unit 34, and output the result to the FEC decoder unit 33d3. .

  The FEC decoder unit 33d3 is configured to perform FEC decoding processing on the RAKE combined output of the DPDCH RAKE unit 33d2, extract user data, and transmit the user data to the MAC-e processing unit 33c.

  The RGCH RAKE unit 33d4 is configured to perform despreading processing and RAKE combining processing on the rate grant channel RGCH in the downlink signal transmitted from the RF unit 34, and output the result to the FEC decoder unit 33d5.

  The FEC decoder unit 33d5 is configured to perform an FEC decoding process on the RAKE synthesis output of the RGCH RAKE unit 33d4, extract a scheduling signal, and transmit it to the MAC-e processing unit 33c. The scheduling signal includes an allowable transmission rate in the uplink (or a transmission power ratio between the enhanced dedicated physical data channel (E-DPDCH) and the enhanced dedicated physical control channel (E-DPCCH)).

  The FEC encoding unit 33d7 performs FEC encoding processing on the data transmitted from the MAC-e processing unit 33c using the transmission format information (E-TFC) transmitted from the MAC-e processing unit 33c. The channel power setting unit 33d8 is configured to transmit.

  The channel power setting unit 33d8 is configured to set the transmission power of the channel that transmits the data transmitted from the FEC encoding unit 33d7, based on the E-DPCCH power offset information.

  The spreading unit 33d6 is configured to perform spreading processing on the data transmitted from the channel power setting unit 33d8 and transmit the data to the RF unit 34.

  The radio network controller RNC according to the present embodiment is an apparatus positioned above the radio base station NodeB, and is configured to control radio communication between the radio base station NodeB and the mobile station UE.

  As shown in FIG. 8, the radio network controller RNC according to the present embodiment includes an exchange interface 51, an LLC layer processing unit 52, a MAC layer processing unit 53, a media signal processing unit 54, and a base station interface 55. And a call control unit 56.

  The switching center interface 51 is an interface with the switching center 1. The switching center interface 51 is configured to transfer the downlink signal transmitted from the switching center 1 to the LLC layer processing unit 52 and to transfer the uplink signal transmitted from the LLC layer processing unit 52 to the switching center 1. Yes.

  The LLC layer processing unit 52 is configured to perform an LLC (Logical Link Control) sublayer process such as a header of a sequence number or a trailer combining process. The LLC layer processing unit 52 is configured to transmit the uplink signal to the switching center interface 51 and transmit the downlink signal to the MAC layer processing unit 53 after performing the LLC sublayer processing.

  The MAC layer processing unit 53 is configured to perform MAC processing such as priority control processing and header addition processing. After performing the MAC processing, the MAC layer processing unit 53 transmits the uplink signal to the LLC layer processing unit 52 and transmits the downlink signal to the base station interface 55 (or the media signal processing unit 54). It is configured.

  The media signal processing unit 54 is configured to perform media signal processing on audio signals and real-time image signals. The media signal processing unit 54 is configured to transmit the uplink signal to the MAC layer processing unit 53 and transmit the downlink signal to the base station interface 55 after performing the media signal processing.

  The base station interface 55 is an interface with the radio base station NodeB. The base station interface 55 transfers the uplink signal transmitted from the radio base station NodeB to the MAC layer processing unit 53 (or media signal processing unit 54), and the MAC layer processing unit 53 (or media signal processing unit 54). The downlink signal transmitted from is transmitted to the radio base station NodeB.

  The call control unit 56 is configured to perform call admission control processing, channel setting and release processing by layer 3 signaling, and the like.

  Further, the call control unit 56 is configured to notify the mobile station UE of at least one of required reception quality (for example, error rate) and a predetermined control width of the enhanced dedicated physical control channel (E-DPCCH). Yes.

(Operation of the mobile communication system according to the first embodiment of the present invention)
With reference to FIG. 9 thru | or FIG. 11, operation | movement of the mobile communication system which concerns on the 1st Embodiment of this invention is demonstrated.

  First, with reference to FIG. 9, an operation of the radio control station NodeB in the mobile communication system according to the first embodiment of the present invention will be described.

  As illustrated in FIG. 9, in step S1001, the radio base station NodeB receives an uplink signal transmitted from the mobile station UE via the transmission / reception antenna 16, and the amplifier unit 15 of the radio base station NodeB receives the uplink signal. The received power of the uplink signal is amplified.

  In step S1002, the transmission / reception unit 14 of the radio base station NodeB converts the received uplink signal in the radio band into a baseband signal.

  In step S1003, the E-DPCCH RAKE unit 12c in the baseband signal processing unit (uplink configuration) 12 # 1 of the radio base station NodeB receives the enhanced dedicated physical control channel (E-DPCCH) in the received baseband signal. Are subjected to despreading processing and RAKE combining processing.

  In step S1004, in the baseband signal processing unit (uplink configuration) 12 # 1 of the radio base station NodeB, the E-DPCCH decoder unit 12k performs a decoding process on the enhanced dedicated physical control channel E-DPCCH, and performs MAC processing. -e The function unit 121 determines whether or not the enhanced dedicated physical control channel (E-DPCCH) has been correctly received and decoded.

  If it is determined that the data has been correctly received and decoded, in step S1005, the MAC-e functional unit 121 recognizes an acknowledgment signal (Ack based on the CRC error detection result applied to the enhanced dedicated physical data channel (E-DPDCH)). Alternatively, the baseband signal processing unit (downlink configuration) 12 # 2 transmits the delivery confirmation signal (Ack or Nack) to the mobile station UE.

  On the other hand, if it is determined that reception and decoding could not be performed correctly, in step S1006, the MAC-e functional unit 12l does not perform CRC error detection on the enhanced dedicated physical data channel (E-DPDCH), and the delivery confirmation signal (DTX) is generated, and the baseband signal processing unit (downlink configuration) 12 # 2 transmits the delivery confirmation signal (DTX) to the mobile station UE.

  In such a case, the MAC-e functional unit 121 may be configured not to generate a delivery confirmation signal (DTX).

  Secondly, with reference to FIG. 10 and FIG. 11, the operation of the mobile station UE in the mobile communication system according to the first embodiment of the present invention will be described.

  As shown in FIG. 10, in step S2001, the MAC-e processing unit 33c (HARQ processing unit 33c2) of the mobile station UE sends a delivery confirmation signal (Ack or Nack) from the radio base station NodeB within a predetermined transmission time interval. It is determined whether or not it has been received.

  When the delivery confirmation signal (Ack or Nack) is received, in step S2002, the MAC-e processing unit 33c determines that “(required reception quality of the enhanced dedicated physical control channel (E-DPCCH)) × (predetermined control width). ) ”Is increased (see FIG. 11).

  On the other hand, when the delivery confirmation signal (Ack or Nack) has not been received, in step S2003, the MAC-e processing unit 33c determines that “(required reception quality of the enhanced dedicated physical control channel (E-DPCCH)) × (predetermined E-DPCCH power offset is reduced based on the control width) (see FIG. 11).

(Operations and effects of the mobile communication system according to the first embodiment of the present invention)
According to the mobile communication system according to the first embodiment of the present invention, the mobile station UE estimates the reception quality of the enhanced dedicated physical control channel (E-DPCCH) in the radio base station NodeB according to the delivery confirmation signal. When the reception quality of the enhanced dedicated physical control channel (E-DPCCH) does not reach the required reception quality, the E-DPCCH power offset is increased and the reception quality of the enhanced dedicated physical control channel (E-DPCCH) is excessive. If reception quality is reached, lowering the E-DPCCH power offset reduces reception errors of the enhanced dedicated physical data channel (E-DPDCH) due to enhanced dedicated physical control channel (E-DPCCH) quality degradation. Furthermore, the line capacity is degraded due to excessive E-DPCCH power offset. Gukoto can.

It is a functional block diagram of the radio base station of the mobile communication system which concerns on one Embodiment of this invention. FIG. 3 is a functional block diagram of a baseband signal processing unit (uplink configuration) of a radio base station of a mobile communication system according to an embodiment of the present invention. It is a functional block diagram of the MAC-e function part of the baseband signal processing part (configuration for uplink) of the radio base station of the mobile communication system according to the embodiment of the present invention. It is a functional block diagram of the mobile station of the mobile communication system which concerns on one Embodiment of this invention. It is a functional block diagram of the baseband signal processing part of the mobile station of the mobile communication system which concerns on one Embodiment of this invention. It is a functional block diagram of the MAC-e processing unit of the baseband signal processing unit of the mobile station of the mobile communication system according to the embodiment of the present invention. It is a functional block diagram of the layer 1 processing unit of the baseband signal processing unit of the mobile station of the mobile communication system according to an embodiment of the present invention. It is a functional block diagram of the radio network controller of the mobile communication system according to an embodiment of the present invention. 5 is a flowchart illustrating an operation when a radio base station receives an enhanced dedicated physical channel (E-DPCH) in the mobile communication system according to the embodiment of the present invention. 5 is a flowchart illustrating an operation of a mobile station controlling transmission power of an enhanced dedicated physical channel (E-DPCH) in a mobile communication system according to an embodiment of the present invention. FIG. 3 is a diagram for explaining an operation of a mobile station controlling transmission power of an enhanced dedicated physical channel (E-DPCH) in a mobile communication system according to an embodiment of the present invention. 1 is an overall configuration diagram of a general mobile communication system. It is a figure for demonstrating the operation | movement at the time of transmitting bursty data in the conventional mobile communication system. It is a figure for demonstrating the operation | movement at the time of controlling the transmission rate in an uplink in the conventional mobile communication system. It is a figure which shows the channel structure of the uplink used in the mobile communication system to which the uplink enhancement is applied. It is a sequence diagram which shows the operation | movement of the retransmission control process in the conventional mobile communication system. It is a figure for demonstrating the soft combining in the conventional mobile communication system. It is a figure for demonstrating the stop and weight in the conventional mobile communication system. It is a figure for demonstrating the problem in the conventional mobile communication system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Switching station, NodeB ... Wireless base station, 11 ... HWY interface, 12, 33 ... Baseband signal processing part, 12a ... DPCCH RAKE part, 12b ... DPDCH RAKE part, 12c ... E-DPCCH RAKE part, 12d ... E- DPDCH RAKE unit, 12e ... HS-DPCCH RAKE unit, 12f ... RACH processing unit, 12g ... TFCI decoder unit, 12h, 12m ... buffer, 12i, 12n ... re-despreading unit, 12j, 12o, 33d3, 33d5 ... FEC decoder unit , 12k ... E-DPCCH decoder unit, 12l ... MAC-e functional unit, 12l1 ... reception processing unit, 12l2, 33c2 ... HARQ processing unit, 12l3 ... scheduling unit, 12p ... MAC-hs functional unit, 13, 56 ... call control , 14 ... transmitting / receiving unit, 15 ... amplifier unit, 16, 35 ... Transmission / reception antenna, UE ... mobile station, 31 ... bus interface, 32 ... call processing unit, 34 ... RF unit, 33a ... RLC processing unit, 33b ... MAC-d processing unit, 33c ... MAC-e processing unit, 33c1 ... E- TFC selection unit, 33c3 ... E-DPCCH power offset determination unit, 33d ... layer 1 processing unit, 33d1 ... DPCCH RAKE unit, 33d2 ... DPDCH RAKE unit, 33d4 ... RGCH RAKE unit, 33d6 ... spreading unit, 33d7 ... FEC encoding unit , RNC: Radio network controller, 51: Switching center interface, 52: LLC layer processing unit, 53: MAC layer processing unit, 54: Media signal processing unit, 55: Base station interface

Claims (9)

In the uplink, the mobile station is configured to transmit a transmission power reference channel and a target control channel from the mobile station to the radio base station, and the target control channel has a transmission power offset with respect to the transmission power reference channel. A mobile communication system configured as follows:
The radio base station is configured to transmit an acknowledgment signal of a data channel corresponding to the target control channel to the mobile station,
The mobile communication system, wherein the mobile station is configured to control the transmission power offset according to a delivery confirmation signal transmitted from the radio base station.   The radio base station is configured to transmit a delivery confirmation signal indicating reception of the data channel and a decoding result only when the radio base station correctly decodes the target control channel. Mobile communication system.   The mobile station is configured to maintain or lower the transmission power offset when receiving the acknowledgment signal indicating the reception and decoding results of the data channel, and the data channel within a predetermined period. The mobile communication system according to claim 2, wherein the mobile communication system is configured to increase the transmission power offset when the delivery confirmation signal indicating the reception and decoding results is not received. The mobile station
(Required reception quality of the target control channel) × (predetermined control width)
Is configured to increase the transmit power offset based on
(1-required reception quality of the target control channel) × (the predetermined control width)
4. The mobile communication system according to claim 3, wherein the mobile communication system is configured to reduce the transmission power offset based on   5. The radio network controller according to claim 4, further comprising a radio network controller configured to notify the mobile station of at least one of required reception quality of the target control channel and the predetermined control width. Mobile communication system. In the uplink, the mobile station is configured to transmit a transmission power reference channel and a target control channel from the mobile station to the radio base station, and the target control channel has a transmission power offset with respect to the transmission power reference channel. A mobile station used in a mobile communication system configured as follows:
A transmission power offset control unit configured to receive a delivery confirmation signal of a data channel corresponding to the target control channel from the radio base station and control the transmission power offset according to the delivery confirmation signal; Mobile station to be.   The transmission power offset control unit is configured to maintain or reduce the transmission power offset when receiving the delivery confirmation signal indicating the reception and decoding results of the data channel, and within a predetermined period, The mobile station according to claim 6, wherein the mobile station is configured to increase the transmission power offset when the delivery confirmation signal indicating the reception and decoding results of the data channel is not received. The transmission power offset control unit
(Required reception quality of the target control channel) × (predetermined control width)
Is configured to increase the transmit power offset based on
(1-required reception quality of the target control channel) × (the predetermined control width)
8. The mobile station according to claim 7, wherein the mobile station is configured to reduce the transmission power offset based on In the uplink, the mobile station is configured to transmit a transmission power reference channel and a target control channel from the mobile station to the radio base station, and the target control channel has a transmission power offset with respect to the transmission power reference channel. A radio base station used in a mobile communication system configured as follows:
The mobile station is configured to transmit a delivery confirmation signal indicating reception and decoding results of a data channel corresponding to the target control channel only when the target control channel is correctly decoded. A wireless base station.

Images