JP2010098581A - Mobile station device, base station device, and mobile communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform abnormality detection processing on a radio link in an intermittent receiving mode. <P>SOLUTION: The invention relates to a mobile station device 30 that performs a continuous receiving operation or an intermittent receiving operation while connected to a base station device 50. In the case of Short Discontinuous reception (DRX), the mobile station device 30 performs downlink wireless measurement only during a reception ON period. In the case of Long DRX, meanwhile, the downlink wireless measurement is continued also after the end of the reception ON period in accordance with a downlink radio status measured during the reception ON period. Furthermore, during the reception ON period to perform receiving operation, the mobile station device 30 receives from the base station device 50 information designating an intermittent receiving operation period to perform the intermittent receiving operation and a period to perform a radio link measurement of the other base station device. On the basis of the information received, the intermittent receiving operation is performed, and the radio link measurement of the other base station device, that is not connected, is performed within the reception ON period not to perform any receiving operation. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a mobile station apparatus, a base station apparatus, and a mobile communication system that perform uplink radio link connection processing.

  In the 3rd Generation Partnership Project (3GPP), the W-CDMA system is standardized as a third generation cellular mobile communication system, and services are started sequentially. In addition, HSDPA with higher communication speed has been standardized and the service is about to start. On the other hand, in 3GPP, the evolution of third generation radio access (Evolved Universal Terrestrial Radio Access, hereinafter referred to as “EUTRA”) is being studied. An OFDM (Orthogonal Frequency Division Multiplexing) scheme has been proposed as a downlink of EUTRA. Also, a single carrier communication scheme of DFT (Discrete Fourier Transform) -Spread OFDM scheme has been proposed as an uplink of EUTRA.

  FIG. 7 is a diagram showing a channel configuration of the mobile communication system. As shown in FIG. 7, the downlink of EUTRA includes a downlink pilot channel DPiCH (Downlink Pilot Channel), a downlink synchronization channel DSCH (Downlink Synchronization Channel), a downlink shared channel PDSCH (Physical Downlink Shared Channel), and downlink control. It consists of a channel PDCCH (Physical Downlink Control Channel) and a common control channel CCPCH (Common Control Physical Channel).

  Also, as shown in FIG. 7, the uplink of EUTRA includes uplink pilot channel UPiCH (Uplink Pilot Channel), random access channel RACH (Random Access Channel), uplink shared channel PUSCH (Physical Uplink Shared Channel), uplink It is comprised by the control channel PUCCH (Physical Uplink Control Channel) (nonpatent literatures 1 and 2).

  8 and 9 are diagrams illustrating a downlink configuration. As shown in FIGS. 8 and 9, one resource block is composed of 12 subcarriers and 7 OFDM symbols. Then, the downlink shared channel PDSCH is allocated to at least one mobile station apparatus using two resource blocks. At this time, the downlink control channel PDCCH uses the first to third symbols in 1 TTI, and the downlink shared channel PDSCH uses the remaining OFDM symbols. Further, the downlink pilot channel DPiCH is arranged in a Scattered format in 1 TTI as shown in FIG. FIG. 8 shows an example in which the base station apparatus has two transmission antennas, and there are two types of pilot symbols. A downlink is composed of a plurality of resource blocks.

  FIG. 10 is a diagram illustrating an example of the intermittent reception operation. As shown in FIG. 10, the downlink shared channel PDSCH reception includes a continuous reception mode and a discontinuous reception (DRX) mode. Intermittent reception is introduced to reduce power consumption of the mobile station apparatus. In the intermittent reception mode, parameters such as an intermittent reception interval (reception ON interval or DRX interval) are designated from the base station device to the mobile station device, and the mode shifts from the continuous reception mode to the intermittent reception mode.

  When entering the intermittent reception mode, the mobile station apparatus monitors the downlink control channel PDCCH during the reception interval designated by the base station apparatus. When the downlink shared channel PDSCH is allocated to the downlink control channel PDCCH, the reception ON period is extended and the data of the downlink shared channel PDSCH is received.

  Further, the intermittent reception mode includes Short DRX and Long DRX, and the intermittent reception mode is first entered from the Short DRX. Then, when the downlink shared channel PDSCH is not allocated in a certain period, the short DRX is shifted to the Long DRX. Note that the Short DRX interval is 2 ms to 256 ms, and the Long DRX interval is 10 ms to 2560 ms. Each is designated by the base station apparatus.

  FIG. 11 is a diagram illustrating an uplink channel configuration. As shown in FIG. 11, one resource block is composed of 12 subcarriers and 7 symbols in the uplink as in the downlink. Then, uplink shared channel PUSCH is allocated to at least one mobile station apparatus using two resource blocks. In addition, the random access channel RACH uses 6 resource blocks as one random access channel, prepares a plurality of random access channels RACH, and supports access from a large number of mobile station apparatuses.

  The purpose of using the random access channel RACH is to synchronize the mobile station apparatus that is not synchronized with the base station apparatus in the uplink, and also transmits several bits of information such as a scheduling request to allocate radio resources, It is also considered to shorten the connection time (Non-Patent Document 2).

  The random access channel RACH has two access methods: contention based random access (Contention based Random Access) and non-contention based random access (Non-contention based Random Access). The Contention based Random Access is a random access that may collide between mobile stations, and is a random access that is normally performed. On the other hand, Non-contention based Random Access is random access in which no collision occurs between mobile stations, and in special cases such as handover in order to quickly synchronize the uplink between the mobile station apparatus and the base station apparatus. The base station apparatus takes the lead. Note that the base station apparatus may cause the mobile station to execute Contention based Random Access when the mobile station apparatus cannot execute Non-contention based Random Access.

  In the random access channel RACH, only the random access preamble is transmitted for uplink synchronization. The random access preamble includes a signal pattern representing information, and several bits of information can be expressed by preparing several tens of types of random access preambles. At present, it is assumed that 6-bit information is transmitted, and it is assumed that 64 types of random access preambles are prepared.

  The 6-bit information is assumed to be assigned information such as 5 bits for random ID and the remaining 1 bit for downlink path loss / CQI (Non-patent Document 3).

  FIG. 12 is a diagram illustrating an example of a contention based random access procedure. First, the mobile station apparatus selects a random access preamble from the random ID, downlink path loss / CQI information, and the like, and transmits the random access preamble on the random access channel RACH (message 1 (step S11)).

  When the base station apparatus receives the random access preamble from the mobile station apparatus, the base station apparatus calculates a synchronization timing shift between the mobile station and the base station from the random access preamble, and performs scheduling to transmit an L2 / L3 (Layer2 / Layer3) message. A temporary C-RNTI (Temporary Cell-Radio Network Temporary Identity) is assigned, and a random access preamble is transmitted to the downlink control channel PDCCH and the random access preamble is transmitted to the random access channel RACH. Radio Network Temporary Identity), synchronization timing shift information (Timing Advance), scheduling information, Temporary C-RNTI and received random access to downlink shared data channel PDSCH A random access response including the random access preamble number (or random ID) of the preamble is transmitted (message 2 (step S12)).

  When the mobile station apparatus confirms that the RA-RNTI is present in the downlink control channel PDCCH, the mobile station apparatus confirms the content of the random access response arranged in the downlink shared data channel PDSCH and transmits the transmitted random access preamble number (or random ID). ) Is extracted, synchronization timing shift information is acquired, uplink transmission timing is corrected, and an L2 / L3 message including at least C-RNTI (or Temporary C-RNTI) is included in the scheduled radio resource. Transmit (message 3 (step S13)).

  When the base station apparatus receives the L2 / L3 message from the mobile station apparatus, a collision occurs between the mobile station apparatuses using the C-RNTI (or Temporary C-RNTI) included in the received L2 / L3 message. A contention resolution for determining whether or not there is is transmitted to the mobile station apparatus (message 4 (step S14)) (Non-patent Document 3).

  In the continuous reception mode, the mobile station apparatus measures the quality of the radio link and detects an abnormality in the radio link. FIG. 13 is a diagram illustrating processing when a radio link abnormality (wireless link problem) is detected. When the mobile station apparatus constantly measures the downlink pilot channel DPiCH and the reception quality of the downlink pilot channel DPiCH (for example, an average value of 200 ms) falls below a certain threshold a, a radio link error ( radio link problem) detection (i), and the timer T1 is started, and the recovery period A is started.

In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (ii). Here, when it has recovered above the threshold value b, it returns to the continuous reception state. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus can be made within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.
3GPP TS (Technical Specification) 36.211, V8.30 (2008-05), Technical Specification Group Radio Access Network, Physical Channel and Modulation (Release 8) 3GPP TS (Technical Specification) 36.212, V8.30 (2008-05), Technical Specification Group Radio Access Network, Multiplexing and channel coding (Release 8) 3GPP TS (Technical Specification) 36.300, V8.50 (2008-05), Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN), Overall description Stage2 3GPP TR (Technical Report) 25.814, V7.0.0 (2006-06), Physical layer aspects for evolved Universal Terrestrial Radio Access (UTRA)

  However, only the radio link abnormality detection process in the continuous reception mode is currently defined. If the radio link abnormality process in the intermittent reception mode is performed in the same manner as the radio link abnormality detection process in the continuous reception mode, the detection process is performed using the reception quality of the downlink pilot channel DPiCH continuous for a certain period. In the case of Long DRX with a long DRX interval, it takes several tens of seconds just to calculate the average value of the downlink pilot channel DPiCH. Moreover, the value calculated in such a long time is not suitable for the quality of the radio link environment.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a mobile station device, a base station device, and a mobile communication system that perform radio link abnormality detection processing in an intermittent reception mode.

  (1) In order to achieve the above object, the present invention takes the following measures. That is, the mobile station device of the present invention is a mobile station device that performs continuous reception operation or intermittent reception operation while connected to the base station device, and when performing intermittent reception operation at a specific reception interval, It is characterized in that radio link measurement different from the case of performing continuous reception operation is performed.

  In this way, when intermittent reception operation is performed at a specific reception interval, radio link measurement different from that in continuous reception operation is performed, so even if a radio link abnormality is detected, radio link recovery is performed early. Processing can be performed. Further, since intermittent reception operation is considered, it is possible to reduce power consumption.

  (2) When the mobile station apparatus of the present invention performs an intermittent reception operation at a reception interval other than the specific reception interval, the mobile station apparatus performs the same radio link measurement as when performing a continuous reception operation, When the intermittent reception operation is performed at the reception interval, the radio link measurement is different from the case of performing the continuous reception operation.

  As described above, when the intermittent reception operation is performed at a reception interval other than the specific reception interval, the same radio link measurement as when the continuous reception operation is performed is performed while the intermittent reception operation is performed at the specific reception interval. Since the radio link measurement different from that in the case of performing the continuous reception operation is performed, it is possible to switch the method of the radio link measurement according to the interval of the intermittent reception operation. As a result, even when a radio link abnormality is detected, it is possible to perform radio link recovery processing at an early stage. Further, since intermittent reception operation is considered, it is possible to reduce power consumption.

  (3) Further, the mobile station apparatus of the present invention is characterized in that, based on a radio link measurement result measured during the reception period of the intermittent reception operation, radio link measurement different from that during the continuous reception operation is performed. .

  In this way, since the radio link measurement different from that in the continuous reception operation is performed based on the radio link measurement result measured during the reception period of the intermittent reception operation, the accurate radio link is maintained while maintaining the DRX operation. Can be measured.

  (4) Further, the mobile station apparatus of the present invention includes a reception ON period in which a reception operation is performed from the base station apparatus, an intermittent reception operation period in which an intermittent reception operation is performed, and a period in which radio link measurements of other base station apparatuses are performed. Receiving specified information, performing intermittent reception operation based on the received information, and performing radio link measurement of another base station apparatus not connected within a reception OFF period in which reception operation is not performed It is said.

  With this configuration, it is possible to perform radio link measurement of another base station apparatus that is not connected within a reception OFF period in which no reception operation is performed.

  (5) Further, the mobile station apparatus of the present invention is characterized in that after the radio link measurement of the other base station apparatus is performed, the radio link measurement of the currently connected base station apparatus is performed.

  As described above, after the radio link measurement of another base station apparatus is performed, the radio link measurement of the currently connected base station apparatus is performed, so the radio link measurement of the connected base station apparatus is performed during the reception OFF period. Power consumption can be reduced as compared with the case of performing alone.

  (6) Further, the mobile station apparatus of the present invention receives information specifying a reception ON period for performing a reception operation and an intermittent reception operation period for performing an intermittent reception operation from the base station apparatus, and the reception ON period and intermittent The intermittent reception operation is performed based on the reception operation period, and the radio link measurement is performed within the reception ON period.

  As described above, since the intermittent reception operation is performed based on the reception ON period and the intermittent reception operation period, and the radio link measurement is performed within the reception ON period, the mobile station apparatus does not need to consider each state. In addition, the base station device can control the intermittent reception operation of the mobile station device.

  (7) Moreover, the base station apparatus of the present invention is a base station apparatus that accommodates a mobile station apparatus that performs continuous reception operation or intermittent reception operation when connected, and when the mobile station apparatus performs the intermittent reception operation. A table in which a reception ON period for performing a reception operation and an intermittent reception operation period for performing an intermittent reception operation are associated with each other, and a reception ON period and an intermittent reception operation period are selected and selected for each mobile station device from the table. Information specifying the reception ON period and the intermittent reception operation period is notified to the mobile station apparatus.

  Thus, the base station apparatus selects the reception ON period and the intermittent reception operation period for each mobile station apparatus from the table, and notifies the mobile station apparatus of information specifying the selected reception ON period and intermittent reception operation period. It becomes possible to control the intermittent reception operation of the mobile station apparatus. Also, the mobile station device does not need to consider each state.

  (8) Moreover, the mobile communication system of the present invention is characterized by comprising the mobile station apparatus according to any one of claims 1 to 5 and a base station apparatus.

  With this configuration, when intermittent reception operation is performed at a specific reception interval, radio link measurement is performed differently from continuous reception operation, so even when a radio link abnormality is detected, radio link recovery is performed early. Processing can be performed. Further, since intermittent reception operation is considered, it is possible to reduce power consumption.

  (9) Further, the mobile communication system of the present invention is characterized by comprising the mobile station device according to claim 6 and the base station device according to claim 7.

  According to this configuration, since the intermittent reception operation is performed based on the reception ON period and the intermittent reception operation period, and the radio link measurement is performed within the reception ON period, the mobile station apparatus does not need to consider each state. . In addition, the base station device can control the intermittent reception operation of the mobile station device.

  According to the present invention, when the intermittent reception operation is performed at a specific reception interval, the radio link measurement is performed differently from the case of performing the continuous reception operation. Recovery processing can be performed. Further, since intermittent reception operation is considered, it is possible to reduce power consumption.

(First embodiment)
Next, embodiments according to the present invention will be described with reference to the drawings. In this embodiment, the system shown in FIG. 7 is assumed for the channel configurations of the uplink and the downlink. The downlink shared channel PDSCH reception includes a continuous reception mode and a discontinuous reception (DRX) mode. Further, a communication system in which there is a short time interval DRX (Short DRX) and a long time interval DRX (Long DRX) is assumed.

  In the intermittent reception mode, a parameter such as an intermittent reception interval (reception ON interval or DRX interval) is designated from the base station device to the mobile station device, and the mode is shifted from the continuous reception mode to the intermittent reception mode. When the intermittent reception mode is entered, the downlink control channel PDCCH during the reception ON interval designated by the base station apparatus is monitored, and when the downlink shared channel PDSCH is allocated, the reception ON period is extended and the downlink The data of the link shared channel PDSCH is received.

  There are short DRX and long DRX in the intermittent reception mode, and the intermittent reception mode is first entered from the short DRX. Then, when the downlink shared channel PDSCH is not allocated in a certain period, the short DRX is shifted to the Long DRX. Parameters related to DRX (DRX interval, reception ON period, etc.) are reported from the base station apparatus to the mobile station apparatus.

  In the case of Short DRX, even if the downlink radio measurement is performed only during the reception ON period, there is no problem as long as the time spent for the measurement can follow the fluctuation of the radio link, but in the case of Long DRX, in the downlink DRX Since it cannot follow radio fluctuations, only a measurement result in a certain time range is meaningful. Therefore, in the case of Short DRX, the downlink radio measurement is performed only during the reception ON period. In the case of Long DRX, the downlink radio measurement is performed according to the downlink radio state measured in the reception ON period. Try to continue later. In this way, accurate radio link measurement can be performed while maintaining DRX operation.

  1A to 1C are diagrams illustrating an operation example of Long DRX. In the case of Long DRX as shown in FIG. 1A, as shown in FIG. 1B, first, downlink measurement (reception quality measurement of downlink pilot channel DPiCH) is performed only during the reception ON period. If the downlink reception quality measurement result during the reception ON period is equal to or greater than the predetermined value α, the DRX reception OFF period starts. When the downlink reception quality measurement result in the reception ON period is equal to or less than the predetermined value α, as shown in FIG. 1C, the reception ON period is continued and the downlink reception quality measurement is continued. Then, the downlink reception quality measurement is performed for the same time or a short time as that during continuous reception, and when the reception quality measurement result is a or less as in the case of continuous reception, a radio link abnormality is detected and shown in FIG. The wireless link abnormality processing as described above is performed.

  On the other hand, when the reception quality measurement result is a or more, the reception OFF period is entered. Even in this case, the Long DRX interval is not changed. That is, only the reception OFF period is shorter than in normal DRX.

  FIG. 2 is a diagram illustrating an operation example of Short DRX. In this case, as in the case of continuous reception, the downlink reception quality is measured only during the reception ON period, and the downlink radio state is determined from the result of a constant reception ON period that is the same as or shorter than that during continuous reception.

  FIG. 3 is a diagram illustrating a schematic configuration of the mobile station apparatus. The mobile station device 30 includes a data control unit 31, a DFT-S-OFDM modulation unit 32, a scheduling unit 33, an OFDM demodulation unit 34, a channel estimation unit 35, a control data extraction unit 36, a preamble generation unit 37, and a radio unit 38. Is done. The scheduling unit 33 includes a UL scheduling unit 33a, a control data analysis unit 33b, a control data creation unit 33c, a downlink monitoring unit 33d, and a DRX control unit 33e.

  User data and control data are input to the data control unit 31. The data control unit 31 arranges the input data on the uplink shared channel PUSCH and the uplink control channel PUCCH according to an instruction from the scheduling unit 33. At this time, an uplink pilot channel UPiCH is also arranged. The DFT-S-OFDM modulation unit 32 performs data modulation, performs DFT-S-OFDM signal processing such as DFT conversion, subcarrier mapping, IFFT conversion, CP (Cyclic Prefix) insertion, filtering, etc., and DFT-Spread-OFDM. Generate a signal. Then, the DFT-Spread-OFDM modulated signal is output to radio section 38. The uplink communication scheme is assumed to be a single carrier scheme such as DFT-spread OFDM, but may be a multicarrier scheme such as the OFDM scheme.

  The radio unit 38 up-converts the modulated data to a radio frequency and transmits it to the base station apparatus. Also, the radio unit 38 receives a downlink signal from the base station apparatus, down-converts the signal to a baseband signal, and outputs the received signal to the OFDM demodulation unit 34 and the channel estimation unit 35. The channel estimation unit 35 estimates the radio channel characteristics from the downlink pilot channel DPiCH for each subframe, and outputs the estimation result to the OFDM demodulation unit 34 and the scheduling unit 33. The scheduling unit 33 outputs the measurement result of the downlink reception quality and the estimation result converted into CQI information to notify the base station apparatus of the radio channel estimation result.

  The OFDM demodulator 34 demodulates the received data from the radio channel estimation result of the channel estimator 35. The control data extraction unit 36 separates the received data into user data and control data. Scheduling information, random access response messages, control data related to DRX control (intermittent reception control), and other layer 2 control data are output to the scheduling unit 33, and user data is output to the upper layer. The preamble generation unit 37 randomly selects a random access preamble number to be used in random access according to an instruction from the scheduling unit 33, generates a random access preamble of the selected random access preamble number, and a DFT-S-OFDM modulation unit 32.

  The scheduling unit 33 includes a UL scheduling unit 33a, a control data analysis unit 33b, a control data creation unit 33c, a downlink monitoring unit 33d, and a DRX control unit 33e. The control data analysis unit 33b analyzes the control data input from the control data extraction unit 36, outputs scheduling information included in the scheduling information and the random access response message to the UL scheduling unit 33a, and receives control data related to DRX control. The data is output to the DRX control unit 33e. Further, the control data creation unit 33c is instructed to return a response (success / failure) of the received data.

  The UL scheduling unit 33a instructs the data control unit 31 to arrange user data and control data on the uplink shared channel PUSCH and the uplink control channel PUCCH from the scheduling information. The control data creation unit 33 c creates control data from the response of the received data and the CQI information from the channel estimation unit 35, and outputs the created control data to the data control unit 31. The downlink monitoring unit 33d averages the measurement result from the channel estimation unit 35 and the past estimation result during continuous reception and short DRX, and determines the downlink radio state from the averaged result. Also, during Long DRX, it is determined whether to continue monitoring the downlink radio state from the measurement result from the channel estimation unit 35, and if so, instructs the DRX control unit 33e to extend the reception ON period. To do. Also, when a downlink radio link abnormality is detected during DRX, the DRX controller 33e is instructed to extend the reception ON period.

  The DRX control unit 33e performs power control of the radio unit 38 and other control units in order to perform DRX based on the parameters related to the DRX control from the control data analysis unit 33b (however, in FIG. 3, only the radio unit 38 is shown). To instruct). Further, the reception ON period is changed by an instruction from the downlink monitoring unit 33d or the control data analysis unit 33b.

  4A and 4B are diagrams illustrating an operation of downlink reception quality measurement of the mobile station apparatus. The right end of FIG. 4A and the left end of FIG. 4B are continuous, and are divided into two for convenience of description. In the case of continuous reception, when the mobile station apparatus constantly measures the downlink pilot channel DPiCH and the reception quality of the downlink pilot channel DPiCH (for example, an average value of 200 ms) is below a certain threshold value a, it is shown in FIG. As described above, the radio link problem (i) is detected from the continuous reception state, the timer T1 is started, and the recovery period A is started. In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (ii). Here, when it has recovered above the threshold value b, it returns to the continuous reception state. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus can be made within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.

  When the DRX control parameters (Short DRX interval, Long DRX interval, reception ON period, Short DRX start position, Long DRX transition time, etc.) are notified from the base station apparatus, Short DRX is entered. The reception quality measurement of the downlink pilot channel DPiCH is continuously performed. However, the reception quality is measured only during the reception ON period, and the average value for the same period (for example, the reception ON period is 200 ms) or the short period (for example, the reception ON period and the reception OFF period) is included. When the average value during 200 ms or during the reception ON period is less than a certain threshold value a, as shown in FIG. 13, the radio link abnormality detection (i) is detected from the continuous reception state, and The timer T1 is started, and the recovery period A is started. At this time, the DRX operation is stopped and the state is shifted to the continuous reception state. In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (ii). Here, if it has recovered above the threshold value b, the process returns to the Short DRX. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus can be made within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.

  If there is no reception of the downlink control channel PDCCH for a certain period during the Short DRX, the mobile terminal shifts to the Long DRX. In Long DRX, downlink measurement (reception quality measurement of downlink pilot channel DPiCH) is first performed only during the reception ON period. If the downlink reception quality measurement result during the reception ON period is equal to or greater than the predetermined value α, the DRX reception OFF period starts. When the downlink reception quality measurement result during the reception ON period is equal to or less than the predetermined value α, the reception ON period is continued and the downlink reception quality measurement is continued. Then, downlink reception quality measurement is performed at the same time as during continuous reception (for example, the reception ON period is 200 ms). If the average value is equal to or greater than a certain threshold a, the average value that enters the DRX reception OFF period When it becomes less than a certain threshold value a, as shown in FIG. 13, the radio link abnormality detection (i) is started from the continuous reception state, the timer T1 is started, and the recovery period A is started. At this time, the DRX operation is stopped and the state is shifted to the continuous reception state. In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (i). Here, when it has recovered above the threshold value b, the process returns to the Long DRX. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus is possible within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.

(Second Embodiment)
In the first embodiment, the mobile station apparatus performs downlink reception quality measurement in consideration of the continuous reception state and the DRX state. However, in the second embodiment, the mobile station apparatus does not consider each state. To measure downlink reception. That is, at the time of continuous reception, the reception quality of the downlink pilot channel DPiCH for a certain period is measured, and the downlink quality is determined using the average value. The mobile station apparatus measures the reception quality of the downlink pilot channel DPiCH only during the reception ON period even during DRX, and determines the downlink quality.

  This is performed by controlling the reception ON period. For example, in Short DRX, when the DRX interval is 4 ms or less, the reception ON period is 1 ms, and 400 ms, the downlink pilot channel quality can be measured for 100 ms or more, and the DRX effect is sufficient. is there. Also, in Long DRX, when the DRX interval is 400 ms or more, if the reception ON period is set to 100 ms, the quality of the downlink pilot channel can be measured only during the reception ON period, and the effect of DRX is also the effect of the above-mentioned Short DRX. Same or better than effect. When the DRX interval is 4 ms or more and 400 ms or less, the reception ON period is set to be within the above range.

Assume that the reception quality of the downlink pilot channel DPiCH is measured in 100 ms, and expressed as an equation:
When the reception ON period is less than 100 ms, the reception ON period × β ≧ DRX interval (1)
When the reception ON period is 100 ms or more, the reception ON period × β ≦ DRX interval (2)
However, when the reception ON period is less than 100 ms, considering the effect of DRX,
Reception ON period × β ≧ DRX interval ≧ reception ON period × β ÷ 2 (3).

  Thus, by setting the reception ON period corresponding to the DRX interval set by the base station apparatus, the mobile station apparatus always performs reception quality measurement of the downlink pilot channel DPiCH during the reception ON period.

式（１）と（３）からＤＲＸ間隔と受信ＯＮ期間の関係は以下のようになる。 A specific example is shown. Here, if β is 4, and there is the following DRX interval and reception ON period,

From equations (1) and (3), the relationship between the DRX interval and the reception ON period is as follows.

なお、表２中、（）の値は、式（３）の変わりに式（２）を使用した場合の値を示す。

In Table 2, the value of () indicates the value when the formula (2) is used instead of the formula (3).

  The base station apparatus has a table associating the DRX interval and the reception ON period as described above, and the QoS (Quality of Service) of the data of the mobile station apparatus, the accommodation status of the mobile station apparatus, the status of the downlink radio propagation path, etc. Thus, a suitable reception ON period and DRX interval are selected from the table, and the selected parameters are notified to the mobile station apparatus.

  FIG. 5 is a diagram illustrating a schematic configuration of the base station apparatus. The base station apparatus 50 includes a data control unit 51, an OFDM modulation unit 52, a scheduling unit 53, a channel estimation unit 54, a DFT-Spread OFDM demodulation unit 55, a control data extraction unit 56, a preamble detection unit 57, and a radio unit 58. The The scheduling unit 53 includes a DL scheduling unit 53a, a UL scheduling unit 53b, a control data creation unit 53c, an uplink control channel management unit 53d, and a DRX management unit 53e.

  The data control unit 51 inputs user data and control data, and, according to an instruction from the scheduling unit 53, transmits control data to the downlink common control channel PDCCH, the downlink synchronization channel DSCH, the downlink pilot channel DPiCH, and the common control signaling channel CCPCH. The transmission data and control data for each mobile station apparatus are mapped to the downlink shared data channel PDSCH. The OFDM modulation unit 52 performs OFDM signal processing such as data modulation, serial / parallel conversion of an input signal, IFFT (Inverse Fast Fourier Transform) conversion, CP (Cyclic Prefix) insertion, filtering, and the like to generate an OFDM signal. The radio unit 58 up-converts OFDM-modulated data to a radio frequency and transmits it to the mobile station. Also, the radio unit 58 receives uplink data from the mobile station apparatus, down-converts it into a baseband signal, and sends the received data to the DFT-Spread OFDM demodulation unit 55, the channel estimation unit 54, and the preamble detection unit 57. Output.

  The channel estimation unit 54 estimates the radio channel characteristics from the uplink pilot channel UPiCH, and outputs the radio channel estimation result to the DFT-Spread OFDM demodulation unit 55. Further, the radio channel estimation result is output to the scheduling unit 53 in order to perform uplink scheduling from the uplink pilot channel UPiCH. The uplink communication scheme is assumed to be a single carrier scheme such as DFT-Spread OFDM, but may be a multicarrier scheme such as the OFDM scheme.

  The control data extraction unit 56 confirms the correctness of the received data and notifies the scheduling unit 53 of the confirmation result. If the received data is correct, the received data is separated into user data and control data. Among the control data, layer 2 control data such as downlink CQI information and downlink data success / failure (ACK / NACK) are output to the scheduling unit 53, and other layer 3 control data and user data are Output to upper layer. If the received data is incorrect, it is stored for combining with the retransmitted data, and the combining process is performed when the retransmitted data is received.

  The scheduling unit 53 includes a DL scheduling unit 53a that performs downlink scheduling, a UL scheduling unit 53b that performs uplink scheduling, a control data creation unit 53c, an uplink control channel management unit 53d, and a DRX management unit 53e. The DL scheduling unit 53a includes downlink CQI information reported from the mobile station apparatus, downlink data success / failure (ACK / NACK) information, data information of each user notified from the higher layer, and DRX management unit 53e. Using the input DRX parameters, scheduling is performed for mapping user data and control data to the downlink shared channel PDSCH and the downlink control channel PDCCH from the control data created by the control data creation unit 53c.

  The UL scheduling unit 53b performs scheduling for mapping user data to the uplink shared channel PUSCH based on the uplink radio channel estimation result from the channel estimation unit 54 and the resource allocation request from the mobile station apparatus. The control data creation unit 53c creates a random access response message from the detection result of the ACK / NACK and the preamble detection unit 57 based on whether the uplink reception data is correct, and receives control data such as DRX parameters from the DRX management unit 53e. create. The DRX management unit 53e selects and manages the DRX control parameters from Table 1 according to the status of each mobile station apparatus. Then, in order to notify the mobile station apparatus, a parameter related to DRX is output to the control data creating unit 53c, and also created in the DL scheduling unit 53a to transmit data to the mobile station apparatus operating with the selected parameter. Notify parameters.

  The preamble detection unit 57 detects a random access preamble, calculates a synchronization timing shift amount, and reports the random access preamble number and the synchronization timing shift amount to the scheduling unit 53.

  In the second embodiment, the configuration of the mobile station apparatus is the same as that of the mobile station apparatus according to the first embodiment shown in FIG. The functional difference is that the operation of the downlink monitoring unit 33d is different from that of the downlink pilot channel DPiCH in which the reception ON period is a fixed period (for example, between 100 ms) until the DRX parameter notified from the base station apparatus is within 80 ms. The downlink quality is determined from the average value of the reception quality. When the reception ON period is 100 ms or longer, the reception quality of the downlink pilot channel DPiCH is measured within the range of one reception ON period, and the downlink quality is determined.

  6A and 6B are diagrams illustrating an operation example of the mobile station apparatus. The right end of FIG. 6A and the left end of FIG. 6B are continuous, and are divided into two for convenience of description. In the case of continuous reception, when the mobile station apparatus constantly measures the downlink pilot channel DPiCH and the reception quality of the downlink pilot channel DPiCH (for example, the average value of 100 ms) is below a certain threshold a, it is shown in FIG. As described above, the radio link problem (i) is detected from the continuous reception state, the timer T1 is started, and the recovery period A is started. In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (ii). Here, when it has recovered above the threshold value b, it returns to the continuous reception state. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus is possible within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.

  When the DRX control parameters (Short DRX interval, Long DRX interval, reception ON period, Short DRX start position, Long DRX transition time, etc.) are notified from the base station apparatus, Short DRX is entered. The reception quality measurement of the downlink pilot channel DPiCH is continuously performed. However, the reception quality measurement is performed only during the reception ON period, and when the average value for the same period as during continuous reception (for example, the reception ON period is 100 ms) falls below a certain threshold value a, as shown in FIG. From the continuous reception state, the radio link abnormality is detected (i), the timer T1 is started, and the recovery period A is started. At this time, the DRX operation is stopped and the state is shifted to the continuous reception state. In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (ii). Here, if it has recovered above the threshold value b, the process returns to the Short DRX. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus can be made within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.

  If there is no reception of the downlink control channel PDCCH for a certain period during the Short DRX, the mobile terminal shifts to the Long DRX. In Long DRX, the reception quality of the downlink pilot channel DPiCH is measured only during the reception ON period. That is, the result of downlink reception quality measurement is determined in time at the end of the reception ON period. When the average value is equal to or greater than a certain threshold value a, the DRX reception OFF period starts. When the average value is less than the certain threshold value a, as shown in FIG. Then, the timer T1 is started, and the recovery period A is started. At this time, the DRX operation is stopped and the state is shifted to the continuous reception state. In the recovery period A, the mobile station apparatus checks the quality of the downlink pilot channel DPiCH (ii). Here, when it has recovered above the threshold value b, the process returns to the Long DRX. If it is less than the threshold value b, a radio link error occurs, the timer T2 is started, and the recovery period B is started. In the recovery period B, Content based Random Access is performed and reconnection processing with the base station apparatus is performed (iii). When reconnection with the base station apparatus is possible within the timer T2, the state shifts to the continuous reception state, and when reconnection fails, the state shifts to the non-connection state.

(Third embodiment)
The mobile station apparatus is to periodically measure radio links of different base station apparatuses in the same radio frequency band according to instructions from the base station apparatus. In the present embodiment, radio link measurement by Long DRX is performed when radio link measurement of this different base station apparatus is performed.

  FIG. 14 is a diagram illustrating that radio links of different base station apparatuses in the same radio frequency band are periodically measured. As shown in FIG. 14, the radio link of another base station apparatus is periodically measured during the reception OFF period. At this time, by performing the radio link measurement of the own base station apparatus as shown in FIG. 15, the power consumption of the mobile station apparatus is smaller than that of performing the radio link measurement of the own base station apparatus alone during the reception OFF period. Less is enough. That is, the radio link of the own base station apparatus is measured following the radio link measurement of another base station apparatus. In the case of Short DRX, the radio link is measured only during the reception ON period as in the first embodiment.

  When the mobile station apparatus is instructed by the base station apparatus to perform the reception quality measurement of the downlink pilot channel DPiCH of another base station apparatus at a predetermined interval and for a predetermined period, the mobile station apparatus transmits a downlink pilot of another base station apparatus. The reception quality of the channel DPiCH is measured, and the reception quality of the downlink pilot channel DPiCH of the own base station apparatus is continuously measured after a certain period. At this time, if the measurement for the same period as that during continuous reception (for example, the reception ON period is 100 ms) cannot be performed, the reception quality of the downlink pilot channel DPiCH is measured in multiple times, and the reception quality is increased. judge.

  By doing so, it is possible to perform radio link measurement without increasing the power consumption of the mobile station apparatus while maintaining the basic DRX operation. This operation can also be performed when measuring radio links of base station apparatuses having different frequencies.

  As described above, according to the present embodiment, by performing radio link measurement in consideration of the intermittent reception mode, even when a radio link abnormality is detected, radio link recovery processing can be performed at an early stage. In addition, since intermittent reception is taken into consideration, less power is consumed.

It is a figure which shows the operation example of Long DRX. It is a figure which shows the operation example of Long DRX. It is a figure which shows the operation example of Long DRX. It is a figure which shows the operation example of Short DRX. It is a figure which shows schematic structure of a mobile station apparatus. It is a figure which shows the operation | movement of the reception quality measurement of the downlink of a mobile station apparatus. It is a figure which shows the operation | movement of the reception quality measurement of the downlink of a mobile station apparatus. It is a figure which shows schematic structure of a base station apparatus. It is a figure which shows the operation example of a mobile station apparatus. It is a figure which shows the operation example of a mobile station apparatus. It is a figure which shows the channel structure of a mobile communication system. It is a figure which shows the structure of a downlink. It is a figure which shows the structure of a downlink. It is a figure which shows an example of an intermittent reception operation | movement. It is a figure which shows the channel structure of an uplink. It is a figure which shows an example of the procedure of Contention based Random Access. It is a figure which shows the process at the time of detecting the abnormality of a radio link (problem of a radio link). It is a figure which shows the operation example of the mobile station apparatus in the case of measuring the radio link of another base station apparatus. It is a figure which shows the operation | movement of the reception quality measurement of the downlink of a mobile station apparatus.

Explanation of symbols

30 mobile station device 31 data control unit 32 DFT-S-OFDM modulation unit 33 scheduling unit 33a UL scheduling unit 33b control data analysis unit 33c control data creation unit 33d downlink monitoring unit 33e DRX control unit 34 OFDM demodulation unit 35 channel estimation unit 36 control data extraction unit 37 preamble generation unit 38 radio unit 50 base station apparatus 51 data control unit 52 OFDM modulation unit 53 scheduling unit 53a DL scheduling unit 53b UL scheduling unit 53c control data creation unit 53d uplink control channel management unit 53e DRX management Unit 54 channel estimation unit 55 DFT-S-OFDM demodulation unit 56 control data extraction unit 57 preamble detection unit 58 radio unit

Claims (9)

A mobile station device that performs continuous reception operation or intermittent reception operation while connected to a base station device,
A mobile station apparatus that performs radio link measurement different from the case of performing a continuous reception operation when performing an intermittent reception operation at a specific reception interval.   When an intermittent reception operation is performed at a reception interval other than the specific reception interval, the same radio link measurement is performed as when a continuous reception operation is performed, whereas when an intermittent reception operation is performed at the specific reception interval, continuous The mobile station apparatus according to claim 1, wherein a radio link measurement different from that in the case of performing a reception operation is performed.   The mobile station apparatus according to claim 1 or 2, wherein a radio link measurement different from that during the continuous reception operation is performed based on a radio link measurement result measured during a reception period of the intermittent reception operation.   From the base station apparatus, information specifying a reception ON period for performing a reception operation, an intermittent reception operation period for performing an intermittent reception operation, and a period for performing radio link measurement of another base station apparatus are received, and based on the received information 3. The mobile station according to claim 1, wherein the mobile station performs an intermittent reception operation and performs radio link measurement of another base station apparatus that is not connected within a reception OFF period in which the reception operation is not performed. apparatus.   5. The mobile station apparatus according to claim 4, wherein after the radio link measurement of the other base station apparatus is performed, the radio link measurement of the base station apparatus being continuously connected is performed.   Information specifying a reception ON period for performing a reception operation and an intermittent reception operation period for performing an intermittent reception operation is received from the base station apparatus, an intermittent reception operation is performed based on the received information, and within the reception ON period The mobile station apparatus according to claim 1 or 2, wherein radio link measurement is performed on the mobile station apparatus. A base station device that accommodates a mobile station device that performs continuous reception operation or intermittent reception operation when connected,
When the mobile station apparatus performs an intermittent reception operation, the mobile station apparatus has a table in which a reception ON period for performing a reception operation and an intermittent reception operation period for performing an intermittent reception operation are associated with each other, and is received from the table for each mobile station apparatus. A base station apparatus, wherein an ON period and an intermittent reception operation period are selected, and information specifying the selected reception ON period and intermittent reception operation period is notified to the mobile station apparatus.   A mobile communication system comprising the mobile station apparatus according to any one of claims 1 to 5 and a base station apparatus.   A mobile communication system comprising the mobile station apparatus according to claim 6 and the base station apparatus according to claim 7.

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