JP2007318402A - Base station apparatus and transmission power control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio base station apparatus for preventing the reduction of the number of user accommodation owing to the excessive increase of transmission power. <P>SOLUTION: A reception state monitor part 10 normally monitors whole users' pass delay position information, an SIR value calculation result, and interference wave power. When interference wave having a high power value is suddenly generated in a frequency band to be used owing to the fault of a mobile machine, etc., a TPC bit output control part 9 stops the output of a TPC bit generated in a TPC bit generating part 8, outputs the prescribed TPC bit generated in the reception state monitor part 10, and controls the transmission power of each mobile machine. Consequently, the radio base station prevents the transmission of the TPC bit for continuously raising the transmission power. Besides, since the interference wave from another user is less affected by reception quality deterioration compared with the interference wave owing to the fault of the mobile machine, etc., the reduction of the number of user accommodation in a cell is prevented by reducing the influence of the interference wave owing to the fault, etc. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a radio base station of a mobile communication system, and more particularly to a radio base station receiver.

  In a CDMA (Code Division Multiple Access) communication system, a transmission power control system using a TPC (Transmission Power Control) bit is generally used (see Patent Document 1). In this method, a fixed pilot bit pattern (reference signal pattern) is periodically (slot unit) inserted into the transmission data format, and the pilot bit pattern is despread on the receiving side, and then the SIR representing the desired power-to-interference power ratio. (Signal to Interference Ratio) value is estimated. If this SIR value is larger than the SIR reference value, the base station apparatus generates TCP bits that reduce the transmission power of the mobile device. On the other hand, if the SIR value is smaller than the reference SIR, the base station apparatus generates a TPC bit that increases the transmission power of the mobile device.

  FIG. 5 is a block diagram showing a configuration of a conventional radio base station. Referring to FIG. 5, a conventional radio base station includes a receiving antenna unit 1, a quasi-synchronous detection unit 2, an A / D (Analog / Digital) conversion unit 3, a synchronization acquisition unit 4, a despreading unit 5, and a bit demodulation unit 6. , SIR calculation unit 7, TPC bit generation unit 8, transmission data generation unit 11, spreading unit 12, spread data synthesis unit 13, D / A (Digital / Analog) conversion unit 14, orthogonal modulation unit 15, and transmission antenna unit 16. Have

  The quasi-synchronous detection unit 2 converts the reception signal from the reception antenna unit 1 into a frequency band in which baseband processing is possible, and sends the frequency band to the A / D conversion unit 3. The A / D conversion unit 3 A / D converts the signal from the quasi-synchronous detection unit 2 and sends it to the synchronization acquisition unit 4. The synchronization acquisition unit 4 performs a path search for the signal from the A / D conversion unit 3 using a predetermined spreading code, and obtains path delay amount information of the path having the highest correlation with the spreading code among the detected paths. Send to despreading unit 5.

  The despreading unit 5 despreads the received data using the path delay amount information from the synchronization acquisition unit 4 and sends the received data to the bit demodulation unit 6. The bit demodulator 6 adjusts the phase of the received data from the despreader 5 and sends it to the SIR calculator 7. The SIR calculation unit 7 calculates the SIR value and sends it to the TCP bit generation unit 8. The TPC bit generation unit 8 generates a TPC bit based on the result of comparing the SIR calculation value with the SIR reference value 1C from the higher-level device (not shown), and sends it to the transmission data generation unit 11. If the comparison result is SIR reference value> SIR calculation value, TPC bit generation section 8 generates a TPC bit that increases the transmission power of the mobile device. If SIR reference value <SIR calculation value, TPC bit generation section 8 generates a TPC bit that reduces the transmission power of the mobile device.

  The transmission data generation unit 11 inserts the TPC bit sent from the TPC bit generation unit 8 into the designated data format to create transmission data. The spreading unit 12 spreads the created transmission data using a spreading code. The spread data combining unit 13 combines spread data from the spread unit 12 for a plurality of users. The D / A converter 14 D / A converts the spread data from the spread data combiner 13 and sends an analog signal to the quadrature modulator 15. The orthogonal modulation unit 15 converts the analog signal from the D / A conversion unit 14 into a radio frequency band.

  FIG. 6 is a time chart showing the operation of the conventional radio base station. FIG. 6 shows the passage of time between the base station interference wave power of each user and the state of transmission power of the mobile device when two users are using the same frequency band. When an interference wave having high power is generated in the frequency band used by the user 1 and the user 2 at the timing of A in FIGS. 6A and 6C due to a failure of other mobile devices in the vicinity, Since the user's SIR value is small, TPC bits that increase the transmission power of the mobile devices of user 1 and user 2 are generated. While the interference power is high, the SIR values of user 1 and user 2 are small, so the TPC bits that increase the transmission power of the mobile device are continuously output, as shown in FIGS. 6 (b) and 6 (d). Thus, the transmission power of the mobile devices of the user 1 and the user 2 gradually increases.

At the timing B, the transmission power of the mobile device between the user 1 in FIG. 6B and the user 2 in FIG. 6D is higher than the transmission power at the timing A. . Therefore, even if an interference wave having high power disappears at the timing B in FIG. 6A and FIG. 6C, the transmission power of the user 2 is reduced in reception of the signal from the user 1 at the radio base station. As the interference power cannot be ignored, the SIR calculation value remains small relative to the SIR reference value. Similarly, for user 2, the transmission power of user 1 cannot be ignored as interference power, and the SIR calculation value remains smaller than the SIR reference value. As a result, a TPC bit is generated that further increases the transmission power of the mobile device between the user 1 in FIG. 6B and the user 2 in FIG. 6D.
JP 2001-298767 A

  If an interference wave with a high power suddenly occurs due to a failure of a mobile station in the vicinity, the power of the interference wave increases during reception by the radio base station, and transmission power control is performed to increase the transmission power of each mobile station. Is called. If a state where high-power interference waves are generated continues, transmission power from each mobile station gradually increases by transmission power control. Since the transmission power of each mobile device increases interference with other mobile devices, the influence of interference waves due to the increase in transmission power due to transmission power control is better than the influence of interference waves due to mobile device failures, etc. There is a possibility that reception becomes impossible due to loss of synchronization in order from a mobile device having a poor reception state. As a result, there is a problem that the number of users accommodated in the cell decreases due to the sudden generation of high-power interference waves due to a failure of the mobile device.

  An object of the present invention is to provide a radio base station apparatus that prevents a decrease in the number of users accommodated due to an excessive increase in transmission power.

In order to achieve the above object, the base station apparatus of the present invention provides:
A base station device that controls transmission power of a mobile device,
A synchronization acquisition unit that performs a path search using a predetermined spreading code and detects a path having the highest correlation with the spreading code obtained by the path search;
An SIR calculation unit for calculating an SIR calculation value and interference wave power of the path detected by the synchronization acquisition unit;
A SIR reference value is defined, and if the SIR calculation value calculated by the SIR calculation unit is smaller than the SIR reference value, the transmission power control information for increasing the transmission power is generated, and the SIR calculation value is A transmission power control information generating unit that generates the transmission power control information so as to reduce transmission power if it is greater than the SIR reference value;
Based on the information on the path detected by the synchronization acquisition unit, the SIR calculation value calculated by the SIR calculation unit, and the interference wave power, the transmission power control information when an unexpected increase in interference occurs A reception state monitoring unit that does not use the transmission power control information generated by the generation unit, and determines that it is used when it is not;
Only when it is determined by the reception state monitoring unit that the transmission power control information generated by the transmission power control information generation unit is to be used, the transmission power control information generated by the transmission power control information generation unit is transmitted to the mobile device. A transmission power control information output control unit for notifying the mobile station of transmission power control information of a predetermined pattern when it is determined that the transmission power control information by the transmission power control information generation unit is not used. Have.

  According to the present invention, the reception state monitoring unit constantly monitors all users' path delay amount information, SIR value calculation results, and interference wave power. When an interference wave with a high power value suddenly occurs in the frequency band used due to a mobile device failure, the transmission power control information output control unit outputs the transmission power control information generated by the transmission power control information generation unit. And the predetermined transmission power control information generated by the reception state monitoring unit is output to control the transmission power of each mobile device. The radio base station can prevent transmission of transmission power control information that continuously increases transmission power. Interference waves from other users are less affected by degradation of reception quality compared to interference waves caused by mobile device failures, etc., so the number of users accommodated in the cell can be reduced by reducing the influence of interference waves caused by failures, etc. Can be prevented.

  When the reception state monitoring unit determines that the transmission power control information is not used, the transmission power control information output control is performed on the transmission power control information of the predetermined pattern that keeps the transmission power of the mobile station in a certain range. The transmission power control information control unit may notify the mobile device of the transmission power control information from the reception state monitoring unit.

  According to this, when an interference wave having a high power value suddenly occurs in a frequency band used due to a failure of the mobile device or the like, the reception state monitoring unit keeps the transmission power of the mobile device within a certain range. A reduction in the number of users accommodated can be prevented.

  Further, when the reception state monitoring unit determines that the transmission power control information by the transmission power control information generation unit is not used and sends the transmission power control information of the predetermined pattern to the transmission power control information output control unit, The transmission power control information having a different pattern may be allocated to each mobile device so that the change in transmission power between the mobile devices is canceled out.

  According to this, since the reception state monitoring unit cancels the change in the transmission power between the mobile devices, the influence of the interference power between the mobile devices can be reduced.

  According to the present invention, it is possible to prevent a decrease in the number of users accommodated due to an excessive increase in transmission power.

  Embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating a configuration of a radio base station according to the present embodiment. The radio base station includes a reception antenna unit 1, a quasi-synchronous detection unit 2, an A / D conversion unit 3, a synchronization acquisition unit 4, a despreading unit 5, a bit demodulation unit 6, a SIR calculation unit 7, a TPC bit generation unit 8, TPC bit output control unit 9, reception state monitoring unit 10, transmission data generation unit 11, spreading unit 12, spread data synthesis unit 13, D / A conversion unit 14, orthogonal modulation unit 15, and transmission antenna unit 16 Yes.

  The quasi-synchronous detection unit 2 converts the reception signal from the reception antenna unit 1 into a frequency band in which baseband processing is possible, and sends the frequency band to the A / D conversion unit 3.

  The A / D conversion unit 3 A / D converts the signal from the quasi-synchronous detection unit 2 and sends it to the synchronization acquisition unit 4.

  The synchronization acquisition unit 4 performs a path search for the signal from the A / D conversion unit 3 using a predetermined spreading code. The synchronization acquisition unit 4 sends the path delay amount information of the path having the highest correlation with the spreading code among the detected paths to the despreading unit 5 and the reception state monitoring unit 10.

  The despreading unit 5 despreads the received data using the path delay amount information from the synchronization acquisition unit 4 and sends the received data to the bit demodulation unit 6.

  The bit demodulator 6 adjusts the phase of the received data from the despreader 5 and sends it to the SIR calculator 7.

  The SIR calculator 7 calculates an SIR value indicating the power ratio between the desired signal and the interference signal from the received data received from the bit demodulator 6 and sends it to the TPC bit generator 8.

  The TPC bit generation unit 8 generates a TPC bit based on the result of comparing the SIR reference value 1C from the host device (not shown) with the SIR calculation value calculated by the SIR calculation unit 7. If SIR reference value> SIR calculated value, TPC bit generation section 8 generates a TPC bit that increases the transmission power of the mobile device. On the other hand, if the SIR reference value <the SIR calculation value, the TPC bit generation unit 8 generates a TPC bit that reduces the transmission power of the mobile device.

  When the TPC bit output control unit 9 receives from the reception state monitoring unit 10 a signal for permission to use the TPC bit created by the TPC bit generation unit 8, the TPC bit output control unit 9 sends the TPC bit from the TPC bit generation unit 8 to the transmission data generation unit 11. send. When receiving a signal indicating that the use of the TPC bit created by the TPC bit generation unit 8 is not permitted from the reception state monitoring unit 10, the TPC bit from the reception state monitoring unit 10 is sent to the transmission data generation unit 11.

  The reception state monitoring unit 10 determines whether to use the TPC bit generated by the TPC bit generation unit 8 from the path delay amount information, the SIR calculation result, and the interference wave power value information for all users in use. And the determination result is sent to the TPC bit output control unit 9. The reception state monitoring unit 10 generates a predetermined TPC bit to be used when the TPC bit generated by the TPC bit generation unit 8 is not used, and sends it to the TPC bit output control unit 9.

  The transmission data generation unit 11 generates transmission data by inserting the TPC bits output from the TPC bit output control unit 9 into a predetermined data format, and sends the transmission data to the spreading unit 12.

  The spreading unit 12 spreads the transmission data from the transmission data creating unit 11 with a spreading code and sends it to the spread data combining unit 13.

  The spread data combining unit 13 combines spread data from the spread unit 12 for a plurality of users.

  The D / A converter 14 D / A converts the spread data from the spread data combiner 13 and sends an analog signal to the quadrature modulator 15.

  The orthogonal modulation unit 15 converts the analog signal from the D / A conversion unit 14 into a radio frequency band.

  FIG. 2 is a flowchart showing the operation of the receiving apparatus of this embodiment. The quasi-synchronous detection unit 2 converts the reception signal from the reception antenna unit 1 into a frequency band in which baseband processing is possible, and sends the frequency band to the A / D conversion unit 3. (Step 101). The A / D conversion unit 3 A / D converts the signal from the quasi-synchronous detection unit 2 and sends it to the synchronization acquisition unit 4. (Step 102). The synchronization acquisition unit 4 performs a path search on the signal from the A / D conversion unit 3 using a predetermined spreading code, and the path delay amount information of the reception path having the highest correlation with the spreading code among the detected paths. Is sent to the despreading unit 5 and the reception state monitoring unit 11 (step 103).

  The received data is despread using the path delay amount information from the synchronization acquisition unit 4 and sent to the bit demodulation unit 6. (Step 104). The bit demodulator 6 adjusts the phase of the received data from the despreader 5 and sends it to the SIR calculator 7. (Step 105).

  The SIR calculation unit 7 calculates the SIR value 1D indicating the power ratio between the desired signal and the interference signal, sends the SIR value 1D to the TCP bit generation unit 8, and receives the SIR value 1D and the interference wave power value 1E. This is sent to the unit 8 (step 106). The TPC bit generation unit 8 compares the SIR reference value 1C from the host device with the SIR value from the SIR calculation unit 7 (step 107). If the result of the comparison is SIR reference value> SIR calculated value, the TPC bit generation unit 8 generates a TPC bit that increases the transmission power of the mobile device (step 108). If the result of the comparison is SIR reference value <SIR calculated value, the TPC bit generator 8 generates a TPC bit that reduces the transmission power of the mobile device (step 109).

  The reception state monitoring unit 10 determines whether to use the TPC bit generated by the TPC bit generation unit 8 from the path delay amount information, the SIR calculation result, and the interference wave power value information for all users in use. Judge every. (Step 110). As a result of the determination, when the TPC bit generated by the TPC bit generation unit 8 is used, the reception state monitoring unit 10 sends a use permission signal 1G to the TPC bit output control unit 9. As a result of the determination, when the TPC bit generated by the TPC bit generation unit 8 is not used, a signal 1G not used is sent to the TPC bit output control unit 9 and a predetermined TPC bit 1F is sent to the TPC bit output control unit 9 Send (step 111). The TPC bit output control unit 9 sends either the TPC bit from the TPC bit generation unit 8 or the TPC bit from the reception state monitoring unit 10 to the transmission data generation unit 11 according to the signal 1G (step 112).

  The transmission data generation unit 11 generates transmission data by inserting the TPC bit from the TPC bit output control unit 9 into a predetermined data format, and sends the transmission data to the spreading unit 12. (Step 113). The spreading unit 12 spreads the transmission data from the transmission data creating unit 11 with a predetermined spreading code and sends the spread data to the spread data combining unit 13. The spread data combining unit 13 combines the spread data from the spread unit 12 for a plurality of users (step 114). The D / A converter 14 D / A converts the spread data from the spread data combiner 13 and sends an analog signal to the quadrature modulator 15. (Step 115). The orthogonal modulation unit 15 converts the analog signal from the D / A conversion unit 14 into a radio frequency band. (Step 116).

  FIG. 3 is a block diagram illustrating a configuration of the reception state monitoring unit 10 according to the present embodiment. The reception state monitoring unit 10 includes a TPC bit generation determination unit 31 and processing units 301 to 30n for each user. The user unit processing unit 301 includes a first user reception state determination unit 32, a second user reception state determination unit 33, and a reception path state determination unit 34.

  The first user reception state determination unit 32 receives the SIR calculation value 1D and the interference wave power value 1E from the SIR calculation unit 7. The first user reception state determination unit 32 stores the SIR calculation value from the SIR calculation unit 7 in a memory (not shown), the SIR calculation value 1D, and the SIR calculation value stored in the memory when it was previously input. Calculate the difference between Further, the first user reception state determination unit 32 stores the interference wave power value from the SIR calculation unit 7 in a memory (not shown), and the interference wave stored when the interference wave power value 1E was previously input. Calculate the difference from the power value.

  Then, the first user reception state determination unit 32 compares the difference in the calculated value of the SIR value with a predetermined first threshold, and compares the difference in the interference wave power value with a predetermined second threshold. To do. From the comparison between the difference between the SIR calculation value and the first threshold value, it is determined that the SIR value has decreased by a predetermined value or more, and from the comparison between the difference between the interference wave power value and the second threshold value, the interference wave power value is When it is determined that the value has increased by a predetermined value or more, the first user reception state determination unit 32 starts to send a TPC bit generation control request signal 36 to the second user reception state determination unit 33.

  Further, it is determined that the SIR value is increased by a predetermined value or more from the comparison between the difference between the SIR calculation value and the first threshold value, or the interference wave power value is determined from the comparison between the difference between the interference wave power value and the second threshold value. When it is determined that is increased by a predetermined value or more, the first user reception state determination unit 32 stops sending the TPC bit generation control request signal 36 to the second user reception state determination unit 33.

  The reception path state determination unit 34 receives the path delay amount information 1 </ b> B from the synchronization acquisition circuit 4. The reception path state determination unit 34 stores the path delay amount information 1B in a memory (not shown), and compares the path delay amount information 1B with the path delay amount information stored in the previous memory. If the path delay amount information matches as a result of the comparison, a signal 35 indicating that the reception position is stable is sent to the second user reception state determination unit 33.

  The second user reception state determination unit 33 confirms that the TPC bit generation control request signal 36 from the first user reception state determination unit 32 and the reception position stabilization signal 35 from the reception path state determination unit 34 have been received. Then, a TPC bit generation control request signal 36 is sent to the TPC bit generation determination unit 31.

  Until the next control request signal 36 is received, the TPC bit generation determination unit 31 performs a TPC in a pattern determined in advance so as to keep the transmission power within a certain range for the user's mobile station corresponding to the control request signal 36. Send a bit.

  FIG. 4 is a time chart showing an operation in the reception state monitoring unit 10 of the present embodiment. FIG. 4 shows the interference wave power at the reception of each user's base station, the state of transmission power of the mobile device, and the time lapse of the output of the TPC bit generation determination unit. In FIG. 4, it is assumed that the reception quality is good without changing the reception path positions of two users in the same cell.

  The reception state monitoring unit 10 of the user 1 is connected to the TPC bit output control unit 9 by the TPC bit generation unit 8 until an interference wave having high power due to a failure of the mobile device or the like is input at the timing A in FIG. A signal 1G indicating permission to use the generated TPC bit is sent. Upon receiving the signal 1G, the TPC bit output control unit 9 selects the TPC bit generated by the TPC bit generation unit 8 and sends it to the transmission data generation unit 11.

  When a sudden high power interference wave is input at timing A in FIG. 4A due to a failure of the mobile device, the SIR value calculated by the SIR calculation unit 7 of the user 1 decreases, and the interference wave Power increases. At timing A in FIG. 4A, the reception state monitoring unit 10 of the user 1 converts the signal from use permission to signal 1G representing use disapproval in FIG. 4B, and converts the signal 1G and the TPC bit 1F to the TPC bit. This is sent to the output control unit 9. The TPC bit output control unit 9 that has received the signal 1G indicating the non-permission of use stops the transmission of the TPC bit generated by the TPC bit generation unit 8, and at the timing B in FIG. Switch to TPC bit 1F.

  The radio base station performs the same operation for the user 1 and the user 2, but the reception timing in the base station is different. The reception state monitoring unit 10 starts transmission of a predetermined pattern of TPC bits 1F at a timing B in FIG. At a certain timing, the transmission power of the user 1 is increased and the transmission power of the user 2 is decreased. At the next timing, the transmission power of the user 1 is decreased and the transmission power of the user 2 is increased. While the use non-permission signal 1G is sent from the reception state monitoring unit 10 to the TPC bit output control unit 9, the reception state monitoring unit 10 sends a predetermined pattern of TPC bits to the TPC bit output control unit 9. During this period, the transmission power of the user 1 shown in FIG. 4 (d) and the user 2 shown in FIG. 4 (h) repeatedly increase or decrease the transmission power alternately. Further, as shown in FIGS. 4C and 4G, by controlling the TPC bit pattern of user 1 and the TPC bit pattern of user 2 to be different TPC bit patterns, it is possible to receive the base station. The influence of the interference wave power of other users can be suppressed.

  When the interference wave with high power disappears at the timing C in FIG. 4A, the SIR value of the user 1 increases from the previous SIR value, and the interference wave power value decreases. The reception state monitoring unit 10 converts the signal 1G representing use permission from use disapproval at timing D, and sends the signal 1G to the TPC bit output control unit 10. As a result, the TPC bit output control unit 10 starts sending the TPC bits generated by the TPC bit generation unit 8 of each user to the data creation unit 11.

  Similarly, the user 2 also converts a signal 2G representing use permission from use disapproval at timing D in FIG. 4 (h), and sends the signal 2G to a TPC bit output control unit (not shown). Thereby, the TPC bit output control unit (not shown) sends the TPC bits generated by the TPC bit generation unit (not shown) of each user to the data generation unit (not shown).

  Note that the TPC bit generation unit 8 and the TPC bit output control unit 9 of this embodiment can also be realized by a configuration included in the reception state monitoring unit 10. Alternatively, a threshold value for the number of users may be set in the TPC bit generation determination unit 31 in advance, and the TPC bits generated by the TPC bit generation unit 8 may continue to be used until the number of users using the cell exceeds the threshold value. This is because when the number of users in use is small, a decrease in the user capacity of the cell has little influence on the users.

  The reception path state determination unit 34 has a function of sending a signal indicating a state where the reception position is stable to the second user reception state determination unit 36 if the reception path position is within a predetermined range. Also good.

  As described above, according to the present embodiment, the reception state monitoring unit 10 constantly monitors all users' path delay position information, SIR value calculation results, and interference wave power. When an interference wave having a high power value suddenly occurs in a frequency band used due to a mobile device failure or the like, the TPC bit output control unit 9 stops outputting the TPC bit generated by the TPC bit generation unit 8, A predetermined TPC bit generated by the reception state monitoring unit 10 is output to control the transmission power of each mobile device. As a result, the radio base station can prevent transmission of the TPC bit that continuously increases the transmission power. Interference waves from other users are less affected by degradation of reception quality compared to interference waves caused by mobile device failures, etc., so the number of users accommodated in the cell can be reduced by reducing the influence of interference waves caused by failures, etc. Can be prevented.

  Further, in this embodiment, when the reception state monitoring unit 10 determines that the TPC bit generated by the TPC bit generation unit 8 is not used, the reception state monitoring unit 10 sets a predetermined pattern of TPC bits to keep the transmission power of the mobile device within a certain range. The information may be sent to the TPC bit output control unit 9, and the TPC bit output control unit 9 may notify the mobile device of the TPC bit from the reception state monitoring unit 10.

  As a result, when an interference wave having a high power value suddenly occurs in a frequency band used due to a failure of the mobile device, the reception state monitoring unit 10 keeps the transmission power of the mobile device within a certain range. Can be prevented from decreasing.

  In the present embodiment, the reception state monitoring unit 10 determines that the TPC bits generated by the TPC bit generation unit 8 are not used, and moves when a predetermined pattern of TPC bits is sent to the TPC bit output control unit 9. You may make it allocate the TPC bit which has a different pattern in each mobile station so that the change of the transmission power between machines may be canceled.

  Thereby, since the communication status monitoring unit cancels the change in the transmission power between the mobile devices, the influence of the interference wave power between the mobile devices can be reduced.

It is a block diagram which shows the structure of the wireless base station of this embodiment. It is a flowchart which shows operation | movement of the radio base station of this embodiment. It is a block diagram which shows the structure of the reception condition monitoring part 10 of this embodiment. It is a time chart which shows the operation | movement in the receiving condition monitoring part 10 of this embodiment. It is a block diagram which shows the structure of the conventional radio base station. It is a time chart which shows operation | movement of the conventional radio base station.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reception antenna part 2 Quasi-synchronous detection part 3 A / D conversion part 4 Synchronization acquisition part 5 Despreading part 6 Bit demodulation part 7 SIR calculation part 8 TPC bit generation part 9 TPC bit output control part 10 Reception state monitoring part 11 Transmission data Generation unit 12 Spreading unit 13 Spreading data combining unit 14 D / A conversion unit 15 Orthogonal modulation unit 16 Transmitting antenna unit 101 to 116 steps

Claims (10)

A base station device that controls transmission power of a mobile device,
A synchronization acquisition unit that performs a path search using a predetermined spreading code and detects a path having the highest correlation with the spreading code obtained by the path search;
An SIR calculation unit for calculating an SIR calculation value and interference wave power of the path detected by the synchronization acquisition unit;
A SIR reference value is defined, and if the SIR calculation value calculated by the SIR calculation unit is smaller than the SIR reference value, the transmission power control information for increasing the transmission power is generated, and the SIR calculation value is A transmission power control information generating unit that generates the transmission power control information so as to reduce transmission power if it is greater than the SIR reference value;
Based on the information on the path detected by the synchronization acquisition unit, the SIR calculation value calculated by the SIR calculation unit, and the interference wave power, the transmission power control information when an unexpected increase in interference occurs A reception state monitoring unit that does not use the transmission power control information generated by the generation unit, and determines that it is used when it is not;
When it is determined not to use the transmission power control information by the transmission power control information generation unit, it starts to notify the mobile device of transmission power information of a predetermined pattern, and then the transmission power control generation unit in the reception state monitoring unit A transmission power control information output control unit that returns to a state of notifying the mobile device of the transmission power control information generated by the transmission power control information generation unit when determined to use the transmission power generated by A base station receiving apparatus.   When the reception state monitoring unit determines that the transmission power control information is not used, the transmission power control information of the predetermined pattern that keeps the transmission power of the mobile station in a certain range is transmitted to the transmission power control information output control unit. The base station apparatus according to claim 1, wherein the transmission power control information control unit notifies the mobile device of the transmission power control information from the reception state monitoring unit.   The base station apparatus according to claim 1 or 2, wherein the transmission power control information is a TPC bit for instructing the mobile station to increase or decrease transmission power. The reception state monitoring unit
A reception path state determination unit that detects that the mobile device is at the same point by comparing the path detected this time and the path detected last time in the synchronization acquisition unit;
The SIR calculation unit calculates the SIR reduction amount or SIR increase amount from the SIR calculation value calculated this time and the SIR calculation value calculated last time, and the interference wave power value calculated this time by the SIR calculation unit and the previous time. An interference power decrease amount or an interference power increase amount is calculated from the calculated interference wave power value, the SIR decrease amount is larger than a predetermined first threshold value, and the interference increase amount is larger than a predetermined second threshold value. When it is determined that the transmission power control information by the transmission power control information generation unit is not used, the SIR increase amount is larger than a predetermined first threshold value, and the interference reduction amount is larger than a predetermined second threshold value. A first user reception state determination unit that determines to use transmission power control information by the transmission power control information generation unit;
The first user reception state determination unit determines that the transmission power control information by the transmission power control information generation unit is not used, and the reception path state determination unit detects that the mobile device is at the same point When the transmission power control information generated by the transmission power control information generation unit is determined not to be used, transmission power control information of a predetermined pattern is sent to the transmission power control information output control unit, and the first user reception state determination unit When it is determined to use the transmission power control information by the transmission power control information generation unit, or when the reception path state determination unit detects that the mobile device is not at the same point, transmission by the transmission power control information generation unit A second user reception state that determines that power control information is to be used and does not transmit a predetermined pattern of transmission power control information to the transmission power control information output control unit And a determination unit,
The transmission power control information output control unit notifies the mobile device of the transmission power control information of the predetermined pattern when the reception state monitoring unit determines that the transmission power control information generated by the transmission power control information generation unit is not used. 4. The transmission power control information is notified to the mobile device when the reception state monitoring unit determines that the transmission power control information is used by the transmission power control information generation unit. The base station apparatus according to item 1.   The reception state monitoring unit determines that the transmission power control information from the transmission power control information generation unit is not used and sends the transmission power control information of the predetermined pattern to the transmission power control information output control unit. The base station apparatus according to any one of claims 1 to 4, wherein the transmission power control information having a different pattern is assigned to each mobile station so that a change in transmission power between the mobile stations is offset. A transmission power control method for controlling transmission power of a mobile device by a base station,
Define the SIR reference value in advance,
A path search is performed using a predetermined spreading code, and a path having the highest correlation with the spreading code among the paths obtained by the path search is detected.
Calculating an SIR calculation value and interference wave power of the detected path;
If the calculated SIR calculated value is smaller than the SIR reference value, transmission power control information for increasing transmission power is generated. If the SIR calculated value is larger than the SIR reference value, the transmission power for decreasing the transmission power is generated. Generate control information,
Based on information on the detected path, the calculated SIR value and the interference wave power, the transmission power control information is not used when a sudden increase in interference occurs, and is used otherwise. Then,
When it is determined not to use the transmission power control information, it starts to notify the mobile device of transmission power information of a predetermined pattern, and after that, when it is determined to use the transmission power, the transmission power control information is A transmission power control method for returning to a state of notifying a mobile device.   If it is determined that the transmission power control information is not used, the transmission power control information of the predetermined low-level pattern is generated so as to keep the transmission power of the mobile device within a certain range, and the generated transmission power control information is used as the mobile device. The transmission power control method according to claim 6, which is notified to.   The transmission power control method according to claim 6 or 7, wherein the transmission power control information is a TPC bit for instructing the mobile station to increase or decrease transmission power. By comparing the path detected this time with the path detected last time, it is detected that the mobile device is at the same point,
The SIR decrease amount or SIR increase amount is calculated from the SIR calculation value calculated this time and the SIR calculation value calculated last time, and interference is calculated from the interference wave power value calculated this time and the interference wave power value calculated last time. Calculate the wave power decrease or interference power increase,
When the SIR decrease amount is larger than a predetermined first threshold value and the interference increase amount is larger than a predetermined second threshold value, it is determined that the transmission power control information is not used,
When the SIR increase amount is larger than a predetermined first threshold and the interference decrease amount is larger than a predetermined second threshold, it is determined that the transmission power control information by the transmission power control information generation unit is used,
When it is determined not to use the transmission power control information, it starts to notify the mobile device of transmission power control information of a predetermined pattern, and then when it is determined to use the transmission power control information, the transmission power control information is 9. The transmission power control method according to any one of claims 6 to 8, which is notified to a mobile device.   When the transmission power control information is determined not to be used and the transmission power control information of the predetermined pattern is generated, the transmission having a different pattern in each mobile device so that a change in transmission power between the mobile devices is offset The transmission power control method according to any one of claims 6 to 9, wherein power control information is allocated.

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