JP3942921B2 - Wireless communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio communication apparatus such as a radio relay amplification apparatus, and more particularly to a technique for shortening a time required for path detection of a signal transmitted from a base station apparatus other than a base station apparatus serving as a reference.
[0002]
[Prior art]
For example, in a mobile communication system that performs wireless communication between a base station apparatus and a mobile station apparatus using a direct sequence-code division multiple access (DS-CDMA) system, a signal is spread code ( A spread signal obtained by spreading using a code is transmitted and received wirelessly. Further, such a system is provided with a wireless relay amplification device that relays and amplifies signals communicated between the base station device and the mobile station device.
[0003]
In such a system, for example, a long spreading code (long code) unique to each base station apparatus and a short spreading code unique to each channel multiplexed in the base station apparatus over a plurality of transmission symbol periods. A sequence obtained by multiplying (short code) is used as a spread code for spread spectrum. For example, a scrambling code is used as a long spreading code unique to each base station apparatus, and a channelization code is used as a short spreading code unique to each channel.
[0004]
Further, in such a system, for example, a channel spread only by the channelization code unique to the system by not performing (masking) the spread by the scrambling code for each base station apparatus at a constant period. Are provided at regular intervals and used as a synchronization channel. In such a system, for example, a broadcast channel is provided in downlink communication from a base station apparatus to a mobile station apparatus, and broadcast information such as a transmission power value (broadcast channel transmission power value) of the broadcast channel is transmitted to the broadcast channel. Is used to transmit.
[0005]
FIG. 8 shows a configuration example of a wireless relay amplifying device in the prior art.
In the radio relay amplification device, a signal (downlink signal) wirelessly transmitted from the base station device to the mobile station device is received and amplified, and then wirelessly transmitted to the mobile station device. Relaying and amplifying signals communicated between a base station device and a mobile station device by receiving and amplifying a signal (uplink signal) that is wirelessly transmitted to the device and then wirelessly transmitting the signal to the base station device To do.
[0006]
The radio demodulator 31 demodulates the received signal in the radio frequency band, which is a downlink signal, and down-converts it to a baseband component.
The A / D (Analog to Digital) converter 32 converts the down-converted baseband received signal into a digital signal.
The path detection unit 33 detects the position of the broadcast channel path from the base station apparatus that wirelessly transmits the downlink signal.
The timing generation unit 34 generates timing for despreading the broadcast channel based on the path position notified from the path detection unit 33.
[0007]
The despreading unit 35 despreads the broadcast channel with respect to the digital baseband received signal based on the path timing notified from the timing generation unit 34 and the scrambling code corresponding to the base station apparatus that wirelessly transmits the downlink signal.
Baseband demodulation section 36 demodulates and decodes the received symbols of the broadcast channel after despreading to obtain broadcast channel information.
The broadcast information analysis unit 37 analyzes information in the broadcast channel obtained by demodulation or the like, and acquires a broadcast channel transmission power value and the like.
[0008]
The reception level measurement unit 38 measures the reception level of the broadcast channel using the broadcast channel reception symbol after despreading.
The propagation loss calculation unit 39 calculates the difference between the reception level measured by the reception level measurement unit 38 and the broadcast channel transmission power value obtained from the broadcast information analysis unit 37 as a propagation loss (loss during signal propagation). .
The gain setting unit 40 determines the gain of the radio relay amplifying unit 41 based on the calculated propagation loss and sets the gain in the radio relay amplifying unit 41.
The radio relay amplifying unit 41 amplifies the uplink signal and the downlink signal according to the set value from the gain setting unit 40.
[0009]
Next, an example of the overall operation of the wireless relay amplification apparatus according to the prior art shown in FIG. 8 will be described.
Of the upstream signal (signal from the mobile station device to the base station device) and the downstream signal (signal from the base station device to the mobile station device) input to the wireless relay amplification device, the downstream signal is input to the radio demodulation unit 31. The The radio demodulation unit 31 demodulates an input (reception) signal in the radio frequency band and down-converts it to a baseband component. The received signal down-converted to the baseband component is input to the A / D converter 32 and converted into a digital baseband signal. The digital baseband signal is input to each of the path detection unit 33 and the despreading unit 35.
[0010]
The digital baseband received signal input to the path detection unit 33 is a code obtained by multiplying the scrambling code corresponding to the base station apparatus of the cell in which the wireless relay amplification apparatus is installed and the channelization code of the broadcast channel. Correlation calculation is performed by a matched filter (MF) or the like, and the position of the peak output is detected as the broadcast channel path position from the base station apparatus. The timing generation unit 34 generates the broadcast channel path timing from the base station apparatus based on the path position.
[0011]
The despreading unit 35 despreads the digital baseband received signal at the broadcast channel path timing from the base station apparatus to obtain broadcast channel received symbols. The despread broadcast channel reception symbol is demodulated and decoded by the baseband demodulator 36. The broadcast information analysis unit 37 extracts a broadcast channel transmission power value from the demodulated and decoded broadcast channel demodulation data. The reception level measurement unit 38 measures the broadcast channel reception level. The propagation loss calculation unit 39 calculates the difference between the broadcast channel reception level and the broadcast channel transmission power value as the propagation loss. The gain setting unit 40 determines the gain based on the calculated propagation loss. Then, the wireless relay amplification unit 41 is controlled according to the determined gain setting value.
By performing the operation as described above, the radio relay amplifying unit 41 is controlled so as to set the gain of the radio relay amplifying unit 41 in accordance with a change in propagation loss.
[0012]
Here, the wireless relay amplifying device in the prior art has a problem that it can only deal with the propagation loss of the base station cell at the time when the wireless relay amplifying device is installed. Specifically, for example, a new base station nearby Even when a device is installed, the base station device will follow the base station propagation loss at the time of installation even though there is a base station device with a smaller propagation loss. That is, there is a problem that interference due to over-amplification is increased. In addition, there is a problem that it is not possible to immediately cope with a change in the code arrangement of the base station apparatus after the installation of the wireless relay amplification apparatus.
[0013]
For example, in a booster described in Japanese Patent Application Laid-Open No. 2001-69091, for example, an increase is made based on the transmission power of the reference signal in the base station apparatus, the reception power of the reference signal in the booster, or the noise power in the booster. When controlling the gain to amplify the signal and the gain to amplify the downlink signal, the perch signal of the base station device existing in the vicinity is always scanned, and the signal received at the highest level among the received perch signals Searching is done. And, for example, when a base station device is newly installed near the booster and the propagation loss with the base station device is smaller than the propagation loss with the base station device with the smallest propagation loss so far The gain is adjusted based on a smaller propagation loss related to the newly installed base station apparatus.
[0014]
In such a technology such as a booster, for example, when a new base station device is installed in an area closer to the base station device to be communicated with, the wireless relay amplification device can reduce the transmission power of the wireless relay amplification device. If the transmission power of uplink communication (communication from the radio relay amplification apparatus to the base station apparatus) of the radio relay amplification apparatus is fixed by controlling according to the adjacent base station apparatus with the smallest propagation loss, the proximity The problem that transmission with excessive power is performed for a new base station apparatus installed in a region can be solved.
[0015]
It is to be noted that conventional technical examples relating to a search mode for a synchronization channel, a search mode for a broadcast channel, and the like are shown.
For example, “Long code synchronization in DS-CDMA mobile communication, 1995 Electronic Information Communication Society General Conference B-429 Nakamura, Umeda, Higashi” includes only a short code for downlink communication from a base station device to a mobile station device. Use spreading and perch channel to perform spreading code synchronization at high speed, and use the product of short code and long code to spread the control channel and the long code phase of communication channel to be the same for all communication / control channels, Technology that establishes long code synchronization of the control channel and communication channel based on the long code phase information received by the mobile station device by including phase information of the long code in the first half of the transmission frame for all frames of the perch channel Is described. In addition, in this document, in the asynchronous system between base stations, the phase of the long code generated by the base station device is different between the base station devices, so that long code synchronization is reestablished even when the standby cell is changed. Is described as being necessary.
[0016]
Also, for example, “2-step high-speed initial synchronization method of long code in asynchronous cellular system between DS-CDMA base stations, IEICE Technical Report CS96-19, RCS96-12 (1996-05), Higuchi, Sawahashi, Adachi” In a non-base station asynchronous system in which the spreading code used in each base station apparatus is different to identify the base station apparatus, a symbol spread only with a short code common to each base station apparatus is received in a long code cycle. After detecting the synchronization timing of the long code by detecting in the signal, the correlation between the long code and the received signal is detected based on the long code synchronization timing, and the long code is changed until the correlation value exceeds the threshold value. The long code that exceeds the threshold is the long code corresponding to the base station device that is the transmission source of the received signal. It has been proposed to perform a cell search for identifying (determining) that it is a mobile phone. As described above, the short code synchronization common to the cells is first established, and then the long code synchronization is established using the synchronization information, so that the cell search can be speeded up.
[0017]
Further, for example, “3GPP TS (Technical Specification) 3GTS25.211” describes various channel format examples such as a synchronization channel (SCH) that is a downlink signal used for cell search.
[0018]
[Problems to be solved by the invention]
However, the above-described conventional wireless relay amplification apparatus requires such path detection, for example, when detecting a path of a signal transmitted wirelessly from a base station apparatus other than the base station apparatus currently in communication. There was a problem that the time was long.
The present invention has been made to solve such a conventional problem, and shortens the time required to detect a signal that is wirelessly transmitted and received from a communication station apparatus other than the reference communication station apparatus. An object of the present invention is to provide a wireless communication apparatus capable of performing the above.
[0019]
[Means for Solving the Problems]
In order to achieve the above object, in the wireless communication apparatus according to the present invention, the wireless communication apparatus transmits wirelessly from a communication station apparatus (other communication station apparatus) other than the reference communication station apparatus as follows. Detect the signal to receive.
That is, the signal received by the wireless communication device at a timing outside the predetermined time width including the reception timing of the signal wirelessly transmitted from the reference communication station device (reference communication station device) by the other station signal detection means. A signal transmitted from a communication station device other than the reference communication station device and received by the wireless communication device is detected.
[0020]
Therefore, for example, compared with the conventional case where a signal received by radio transmission from a communication station apparatus other than the reference communication station apparatus is detected from signals received at all timings, the time required for the detection is reduced. It can be shortened. In the present invention, a signal received near the reception timing of a signal wirelessly transmitted from the reference communication station apparatus is often not a signal from another communication station apparatus, and is received away from the reception timing. Considering the actual communication situation that the signal is often a signal from another communication station apparatus.
[0021]
Here, the wireless communication device can be applied to various communication devices such as a wireless relay amplification device, a mobile station device, and a base station device.
Further, as the communication station apparatus, for example, a base station apparatus is used, but other communication apparatuses may be used.
Further, as a reference communication station apparatus, for example, a communication station apparatus that is currently a communication target is used, and as a specific example, a communication station apparatus that minimizes a propagation loss of a received signal is used.
In addition, it is possible to use an aspect in which a plurality of reference communication station apparatuses are used, or an aspect in which the reference communication station apparatuses are switched at appropriate times.
[0022]
In addition, as a mode for detecting a signal that is wirelessly transmitted and received from a communication station device other than the reference communication station device, for example, not only a mode in which the presence of the received signal itself is detected, for example, any received signal Is detected in a state where the communication station apparatus that wirelessly transmitted the reception signal is specified (that is, the communication station apparatus is identified). ) Is included.
[0023]
Various time widths may be used as the predetermined time width including the reception timing of the signal wirelessly transmitted from the reference communication station apparatus. For example, the signal received at the timing inside the time width may be used. It is preferable that a time width is set such that signals from other communication station apparatuses are included in signals received at timings outside the time width without including signals from other communication station apparatuses. In wireless communication using the CDMA system, for example, a time width of ± n chips centering on a reference signal can be used as the time width, where n is a number of 1 or more, A chip is a unit constituting a spread code, and one unit of spread code is formed from a sequence of data values (for example, “1” value and “0” value) of a plurality of predetermined chips.
[0024]
Further, as a mode of detecting a signal received by wireless transmission from a communication station device other than the reference communication station device from signals received at a timing outside the predetermined time width, for example, at the outside timing from the beginning. In addition to a mode in which only received signals are detected as signals from other communication station devices or candidates thereof, for example, after detecting signals received at all timings, they are positioned outside the detection results. It is also possible to use a mode in which only a signal to be detected is detected as a signal from another communication station apparatus or a candidate thereof.
[0025]
Further, as the timing outside the predetermined time width, for example, a timing between the time corresponding to the predetermined lower limit value and the time corresponding to the predetermined lower limit value is preferably used. Specifically, for example, when T1 <T2 <T3 <T4, the predetermined lower limit is T1, the predetermined upper limit is T4, and the predetermined time width is a time from time T2 to time T3. If it is a width, the timing from time T1 to time T2 and the timing from time T3 to time T4 can be used as timing outside the predetermined time width.
[0026]
As a specific example, when wireless communication using a slot is performed, the predetermined time width is set in the time width for one slot, and the time width for the one slot is It is preferable to use a mode in which a signal received by radio transmission from a communication station apparatus other than the reference communication station apparatus is detected from signals received at a timing outside the predetermined time width.
[0027]
Further, in the wireless communication apparatus according to the present invention, in a communication environment in which a multipath occurs such that a signal wirelessly communicated by reflection by a building or the like propagates through a plurality of paths, for example, Path detection is performed on the assumption that a different signal exists for each path signal.
That is, the other station signal detection means, when a signal wirelessly transmitted from a reference communication station apparatus is received as a plurality of path signals arriving via a plurality of paths, The predetermined time width is set on the basis of any one of the path signals, and signals transmitted wirelessly from communication station apparatuses other than the reference communication station apparatus are received as a plurality of path signals arriving via a plurality of paths. If so, the path signal is detected for each path signal.
[0028]
Therefore, as described above, for example, the time required for path detection for other communication station apparatuses can be shortened as compared with the conventional case.
Note that it is possible to use a mode in which a plurality of path signals generated from the same signal are combined by RAKE combining or the like on the receiving side.
[0029]
The radio communication apparatus according to the present invention is a radio communication apparatus used in a mobile communication system using a CDMA system as a preferred mode, and the reception timing is detected after detecting the signal reception timing as follows. The signal is detected in a state where the transmission source is identified. In this mobile communication system, for example, in communication such as a broadcast channel, a control channel, and a communication channel, the communication channel is spread using a product of a channelization code common to the system and a scrambling code unique to each communication station device. A spread signal is wirelessly transmitted from the communication station apparatus.
That is, in the other station signal detecting means of the wireless communication device, the reception timing detecting means detects the reception timing of the spread signal using the channelization code, and the communication station apparatus identification signal detecting means is outside the predetermined time width. A spread signal received by radio transmission from the communication station apparatus is detected using a scrambling code corresponding to a communication station apparatus other than the reference communication station apparatus from among the spread signals received at the timing.
[0030]
Therefore, when detecting a received signal in a state where another base station device that is a transmission source is identified after detecting the reception timing of the signal using a channelization code, for example, compared to the conventional case, for example, The time required for signal detection regarding other communication station apparatuses can be shortened.
[0031]
Here, as the CDMA system, various systems such as a W (Wideband) -CDMA system may be used.
As the mobile communication system, various systems such as a mobile phone system and a simple mobile phone system (PHS: Personal Handy phone System) may be used.
[0032]
As the communication station device, for example, a base station device is used.
In this case, generally, as a channelization code common to the system, for example, a code common to each base station apparatus and a relatively short code is used. In general, the channelization code is made different for each channel to multiplex the signals of each channel.
In this case, generally, a scrambling code unique to each communication station apparatus is a code that is different for each communication station apparatus, and a relatively long code is used. In general, as the scrambling code, a code common to all channels is used. For example, the same scrambling code may be used in two or more communication station apparatuses in which mutual wireless communication does not affect each other.
Also, the base station apparatus may transmit a spread signal spread using only a channelization code, such as a perch channel signal.
[0033]
Further, the spread signal spread using the code that is the product of the channelization code and the scrambling code includes, for example, a portion spread using only the channelization code at a timing such as every predetermined period. In this case, it is possible to establish synchronization of the spread signal based on the portion.
[0034]
As a method of detecting the reception timing of the spread signal using the channelization code, for example, the timing at which the maximum correlation value is obtained by performing the correlation calculation between the reception signal and the channelization code while shifting the calculation timing. It is possible to use a method in which the reception timing is detected on the assumption that the received signal portion corresponding to 1 includes the signal portion spread by the code corresponding to the channelization code.
[0035]
In addition, as a method of detecting a spread signal received wirelessly transmitted from the communication station apparatus using a scrambling code corresponding to a communication station apparatus other than the reference communication station apparatus, for example, based on the detected reception timing, A spread signal whose correlation value is larger than a predetermined threshold value by performing a correlation operation between the scrambling code or the product (a code using the scrambling code) and the received one or a plurality of spread signals. Can be used as a spread signal from the communication station apparatus. Thus, as a mode of detecting the received spread signal using the scrambling code, for example, not only the mode of using the scrambling code itself, but also the scrambling corresponding to the code used for spreading the received spread signal, for example. A mode using a code corresponding to a product of a ring code and another code may be used. Various values may be used as the predetermined threshold. For example, a value that can be used to determine whether the signal is a spread signal spread using the scrambling code is used.
[0036]
The radio communication apparatus according to the present invention is a radio relay amplification apparatus that relays and amplifies signals communicated between a base station apparatus and a mobile station apparatus as a preferred aspect. Control the gain.
In other words, the other station signal detection means detects a signal received and transmitted by radio from a base station apparatus other than the reference base station apparatus, and the relay amplification gain control means detects the received signal by the other station signal detection means. The gain of the relay amplification is controlled corresponding to the base station apparatus that minimizes the propagation loss of the received signal among all the base station apparatuses that have detected the received signal including the apparatus.
[0037]
Therefore, when controlling the gain of relay amplification corresponding to the base station apparatus that minimizes the propagation loss, the time required for signal detection related to other communication station apparatuses is shortened, for example, compared to the conventional case, as described above. can do.
[0038]
Here, various communication devices may be used as the base station device, the mobile station device, and the wireless relay amplification device.
In addition, the wireless communication device such as the wireless relay amplification device according to the present invention detects, for example, the reception timing of a signal received and transmitted from a communication station device such as a base station device serving as a reference, or the signal itself. Functions are also provided.
[0039]
Further, as a mode of relay amplification of a signal communicated between the base station device and the mobile station device, for example, a signal wirelessly transmitted from the base station device is received and amplified and then wirelessly transmitted to the mobile station device. A mode in which one or both of the relay amplification of downlink communication to be performed and the relay amplification of uplink communication to be wirelessly transmitted to the base station apparatus after receiving and amplifying the signal transmitted from the mobile station apparatus are performed. Can be used.
Further, controlling the gain of the relay amplification corresponding to the base station apparatus with the smallest propagation loss may be performed, for example, for either one of the relay amplification of the downlink signal and the relay amplification of the uplink signal, or , May be done for both.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment according to the present invention will be described with reference to the drawings.
FIG. 1 shows a configuration example of a radio relay amplifying device to which the present invention is applied. The radio relay amplifying device includes a radio demodulator 1, an A / D converter 2, a search unit 3, and an inverse. Spreading unit 4, baseband demodulation unit 5, broadcast information analysis unit 6, reception level measurement unit 7, propagation loss calculation unit 8, detection station list holding unit 9, gain setting unit 10, wireless relay amplification Part 11 is provided. The search unit 3 includes a search control unit 21, a path detection unit 22, a timing generation unit 23, a code identification unit 24, and an other station detection processing unit 25.
[0041]
The radio demodulator 1 demodulates the received signal in the radio frequency band, which is a downlink signal, and down-converts it to a baseband component.
The A / D converter 2 converts the down-converted baseband received signal into a digital signal.
The search unit 3 detects the synchronization channel path timing from the digitally converted baseband received signal, identifies the base station scrambling code (the scrambling code of the base station device) associated with the synchronization channel, and performs the scrambling. A base station apparatus corresponding to the ring code is detected, and further, a broadcast channel path is detected based on the base station scrambling code and the path timing.
[0042]
The despreading unit 4 despreads the broadcast channel of the digital baseband received signal based on the path timing from the search unit 3 and the scrambling code of the base station device identified by the search unit 3.
The baseband demodulator 5 demodulates and decodes the received symbol of the broadcast channel after despreading to obtain broadcast channel information.
The broadcast information analysis unit 6 analyzes the demodulated information in the broadcast channel and obtains the broadcast channel transmission power value and the like.
The reception level measurement unit 7 measures the reception level of the broadcast channel using the broadcast channel reception symbol after despreading.
[0043]
The propagation loss calculation unit 8 calculates a difference between the reception level measured by the reception level measurement unit 7 and the broadcast channel transmission power value obtained from the broadcast information analysis unit 6 as a propagation loss.
The detection station list holding unit 9 is information such as the timing detected by the search unit 3, the identified base station scrambling code, and the propagation loss of the base station apparatus corresponding to the scrambling code calculated by the propagation loss calculation unit 8. Is stored as a detected station list, for example, in a memory.
[0044]
The gain setting unit 10 searches, for example, the base station device having the smallest propagation loss from the detection station list, sets the base station device as a parent station, and determines the radio relay amplification unit 11 based on the propagation loss of the parent station. The gain is determined and set in the wireless relay amplification unit 11.
The wireless relay amplification unit 11 performs amplification of the uplink signal and amplification of the downlink signal according to the set value from the gain setting unit 10.
[0045]
Further, the configuration of the search unit 3 will be described in detail.
The search control unit 21 performs search mode setting, code setting, and timing setting. In this example, the search control unit 21 performs search mode setting, code setting, and timing setting for the path detection unit 22, performs search mode setting for the timing generation unit 23, and performs the code identification unit 24. The scrambling code corresponding to the candidate base station apparatus is set, and the pilot path timing is set for the other station detection processing unit 25.
[0046]
The path detection unit 22 detects the path position of the synchronization channel and the broadcast channel path position from the base station apparatus corresponding to the path position by the search mode setting, code setting, and timing setting from the search control unit 21.
The timing generation unit 23 identifies a scrambling code based on the path position from the path detection unit 22, and generates a timing for despreading the broadcast channel.
[0047]
The code identification unit 24 identifies (determines) the base station scrambling code using the timing generated by the timing generation unit 23. In this example, the code identification unit 24 notifies the despreading unit 4 and the detection station list holding unit 9 of a number (code number) for identifying the identified scrambling code.
The other station detection processing unit 25 provides a window for the path detected by the path detection unit 22 based on the pilot path of the current parent station, cancels the path in the window, and cancels the base station other than the parent station. A path from the device (other station) is detected. In this example, the other station detection processing unit 25 notifies the timing generation unit 23 of the detected position of the path from the other station (other station path position). As the pilot path, for example, a path signal having a maximum reception level among a plurality of multipath signals received from the master station is used.
[0048]
Next, an example of operation of the wireless relay amplification apparatus of this example shown in FIG. 1 will be described.
Of the upstream signal (signal from the mobile station device to the base station device) and the downstream signal (signal from the base station device to the mobile station device) input to the wireless relay amplification device of this example, the downstream signal is the wireless demodulator 1. Is input. The radio demodulation unit 1 demodulates an input (reception) signal in the radio frequency band and down-converts it to a baseband component. The received signal down-converted to the baseband component is input to the A / D converter 2 and converted into a digital baseband signal. The converted digital baseband signal is input to the search unit 3 (the path detection unit 22 and the code identification unit 24) and the despreading unit 4, respectively.
[0049]
Here, the operation of the search unit 3 will be described in detail.
In this example, the search unit 3 has three modes: (1) synchronization channel search mode, (2) broadcast channel search mode, and (3) other station search mode. The operation of the search unit 3 in each mode will be described.
[0050]
(1) The synchronization channel search mode will be described.
The synchronization channel search mode is used when the received base station scrambling code is unknown and the scrambling code of the base station apparatus is detected. When the synchronization channel search mode is set by the search control unit 21, the path detection unit 22 starts detecting the synchronization channel path. Specifically, the path detection unit 22 can be configured using a matched filter (MF). In the sync channel search mode, the channelization code for the only sync channel in the system is set in the tap of this MF.
[0051]
FIG. 2A shows a format example of a broadcast channel from one base station apparatus (base station apparatus A), and FIG. 2B shows a format example of a synchronization channel from the base station apparatus A. FIG. 2C shows an example of the MF output (peak position) from the path detection unit 22 when receiving the broadcast channel and the synchronization channel.
[0052]
As shown in (a) and (b) of the figure, the synchronization channel is arranged at a predetermined slot period and spread with the only channelization code for the synchronization channel in the system, and the synchronization channel is arranged. In this case, the broadcast channel is turned off. Further, as shown in FIG. 5C, the MF output has a large correlation at the timing when the signal is spread by the channelization code for the synchronization channel in the transmission signal from the base station apparatus, and the peak of the correlation value is obtained. (The position of the arrow in FIG. 2C) is detected. Based on this peak timing (path position), the timing generation unit 23 generates a synchronization channel path timing. That is, it is assumed that the synchronization channel signal is received at the peak timing.
[0053]
The code identification unit 24 correlates the received signal with a plurality of candidate base station scrambling codes (scramble codes of candidate base station devices) specified by the search control unit 21 at the path timing from the timing generation unit 23. Take. Then, the base station scrambling code having the largest correlation value among the plurality of candidate base station scrambling codes is identified as the scrambling code of the base station apparatus that wirelessly transmitted the received signal.
[0054]
(2) The broadcast channel search mode will be described.
The broadcast channel search mode is used when the received base station scrambling code is known and the broadcast information is demodulated.
When the broadcast channel search mode is set by the search control unit 21, the path detection unit 22 starts the broadcast channel path detection. A sequence obtained by multiplying the base station scrambling code by the channelization code for the broadcast channel is set in the MF tap of the path detection unit 22.
[0055]
FIG. 3 shows an example of the synchronization channel and broadcast channel multiplexed wave from one base station apparatus (base station apparatus A) including a delayed wave and an example of the MF output from the path detection unit 22 at the time of reception. In particular, FIG. 4A shows an example of a preceding wave, FIG. 5B shows an example of a delayed wave, and FIG. 4C shows an MF output (peak). An example of position) is shown.
As shown in FIG. 6C, the MF output has a peak (position of an arrow in FIG. 5C) detected in one symbol period with respect to one signal wave, and when there is a delayed wave, the preceding wave A peak is detected even at a delayed timing. The timing generation unit 23 generates path timings for the preceding wave and the delayed wave based on the peak position (path position). The generated path timing is used by the despreading unit 4 described later.
[0056]
(3) The other station search mode will be described.
The other station search mode is used when a certain base station scrambling code, for example, the scrambling code of the current master station is known, but it is desired to detect the scrambling codes of other base station apparatuses.
When the other station detection mode is set by the search control unit 21, the path detection unit 22 starts synchronization channel path detection in the same manner as in the above-described (1) synchronization channel detection mode. In the MF tap of the path detection unit 22, the only channelization code for the synchronization channel in the system is set.
[0057]
FIG. 4 shows an example of the MF output (peak position) from the path detection unit 22 when receiving multiple waves of a synchronization channel from a plurality of base station apparatuses (base station apparatuses A to D) including delayed waves. It is. In the figure, the horizontal axis (time) indicating the MF peak position is a range having a width corresponding to one slot time.
In the figure, base station apparatus A indicates a master station, and other base station apparatuses B to D indicate base station apparatuses (other stations) other than the master station. In addition, the strongest path from the master station (the path where the peak value is the maximum level) is represented by a black star (★) as a pilot path, and the path from the master station other than the pilot path from the master station ( For example, a preceding wave path and a delayed wave path other than the pilot path are represented by white stars (☆), and paths from other stations are represented by white circles (◯).
[0058]
In the other station search mode, the master station path and the other station path are detected simultaneously. Therefore, the other station detection unit 25 uses the pilot path of the parent station as a reference for the path detected by the path detection unit 22 based on the station information of the parent station held by the detection station list holding unit 9. And a path existing in the window is canceled as a path from the parent station, and a path from another station is detected for a path outside the window.
[0059]
FIG. 4 shows an example of a window provided, and inside the window, four paths from the master station (base station apparatus A) are included. Paths from other stations (base station apparatuses B to D) are included inside one slot time width centered on the pilot path from the station. In this case, specifically, the four paths from the master station shown in the figure (the white star (*) path and the black star (*) path) are canceled, Only the paths from the other stations shown (paths with white circles (◯)) remain. In the example shown in the figure, there are two paths from the other station B, one path from the other station C, and one path from the other station D.
[0060]
By this processing, the signal wave (preceding wave or delay wave) from the master station is deleted from the other station path detection target, and the path candidates from other stations are narrowed down. Then, the timing generation unit 23 generates the timing of the path from the other station based on the path position (other station path position) of the other station path candidate that has been narrowed down. The code identification unit 24 correlates the received signal with a plurality of candidate base station scrambling codes specified by the search control unit 21 at the timing from the timing generation unit 23. Then, for the received signal, the base station scrambling code having the largest correlation value with the received signal among the plurality of candidate base station scrambling codes is used as the scrambling code of the other station used for spreading the received signal. (Other station code) is identified.
[0061]
The operation example of the search unit 3 has been described above, and the following operation example will be described.
With respect to the base station scrambling code identified by the search unit 3 and the detected broadcast channel path timing, the despreading unit 4 despreads the broadcast channel to obtain a received symbol of the broadcast channel. The despread broadcast channel reception symbol is demodulated and decoded by the baseband demodulator 5 to obtain broadcast channel data. The demodulated broadcast channel data is input to the broadcast information analysis unit 6, and the demodulated broadcast channel information is analyzed to obtain a broadcast channel transmission power value and the like. In addition, the reception level measurement unit 7 measures the reception level of the broadcast channel using the despread reception symbols.
[0062]
The reception level measured by the reception level measurement unit 7 and the broadcast channel transmission power value obtained by the broadcast information analysis unit 6 are input to the propagation loss calculation unit 8 and the difference is calculated as the propagation loss. The detection station list holding unit 9 includes the timing detected by the search unit 3, the identified base station scrambling code, the propagation loss for the base station device corresponding to the scrambling code calculated by the propagation loss calculation unit 8, and the like. Information is held as a list of detected stations.
[0063]
FIG. 5 shows an example of the detection station list held in the detection station list holding unit 9. In this detection station list, the serial number (No), reception level, transmission power, propagation loss, scrambling, The ring code number (No) and the path timing are stored in association with each base station apparatus. As a specific example, in the first base station apparatus, the reception level is “100”, the transmission power is “120”, the propagation loss is “20”, the scrambling code number is “0x0000”, The timing is “0x0000”. In this example, the propagation loss “20” of the first base station apparatus among the detected plurality of base station apparatuses is minimized, so that the first base station apparatus is set as the master station. .
[0064]
The gain setting unit 10 sets the base station apparatus having the smallest propagation loss in the detection station list held in the detection station list holding unit 9 as a parent station, and based on the propagation loss of the parent station, the radio relay amplification unit 11 (Gain for uplink signal and gain for downlink signal) are determined, and the determined gain is set for the radio relay amplifying unit 11. The radio relay amplifying unit 11 uses the set value from the gain setting unit 10 as a gain, thereby performing uplink signal amplification and downlink signal amplification.
[0065]
The above is a detailed operation example of each processing unit provided in the wireless relay amplification device of the present example. Next, an example of an operation flow of the wireless relay amplification device of the present example will be described and described.
FIG. 6 shows an example of the operation flow of the wireless relay amplification apparatus of this example in the initial state, and FIG. 7 shows an example of the operation flow of the wireless relay amplification apparatus of this example in the steady state. Note that the operation in the initial state and the operation in the steady state are performed continuously.
[0066]
First, an example of the operation flow in the initial state is shown.
When the apparatus is turned on and reset (step S1), the search unit 3 is activated in the synchronous channel search mode (step S2). The operation of the search unit 3 in the synchronous channel search mode is as described above. The search unit 3 detects a synchronization channel and identifies a base station scrambling code corresponding to the base station apparatus that has detected the synchronization channel (step S3). Then, based on the detected timing and the identified base station scrambling code, the search unit 3 is activated in the broadcast channel search mode (step S4), and the broadcast channel path is detected (step S5). The operation of the search unit 3 in the broadcast channel search mode is as described above.
[0067]
The despreading unit 4 is activated at each path timing of the detected broadcast channel, and the broadcast channel is despread (step S6). The broadcast channel reception symbol after despreading is demodulated and decoded, and the reception level of the broadcast channel is measured (step S7). A broadcast channel transmission power value is extracted from the broadcast channel reception data (step S8), and a propagation loss is calculated from the transmission power value and the measured reception level (step S9).
[0068]
A detected station list related to the base station apparatus is created based on the detected base station scrambling code, timing, and propagation loss of the detected base station apparatus (step S10), and is retained. Immediately after the power is turned on or reset, there is no detected station in the list, so the detected station list is initialized (initialized) by the creation process. At this time, the base station apparatus listed in the list is set as an initial parent station, and a gain is set based on the propagation loss of the parent station (step S11). The wireless relay amplification unit 11 is controlled according to the set gain (step S12).
The initial gain of the wireless relay amplifying apparatus is set through the initial state as described above. After setting the initial gain, the gain is changed in accordance with the change in the electric field. This is the process in the steady state shown below.
[0069]
Hereinafter, an example of an operation flow in a steady state will be shown.
First, a pointer is set to the base station apparatus located at the head of the detection station list (step S21). The search unit 3 is activated in the broadcast channel search mode by the base station scrambling code and timing of the station (base station apparatus) pointed to by the pointer (step S22). The despreading unit 4 is activated at each path timing of the detected broadcast channel, and the broadcast channel is despread (step S23).
[0070]
Then, the broadcast channel reception symbol after despreading is demodulated and decoded, and the reception level of the broadcast channel is measured (step S24). Also, a broadcast channel transmission power value is extracted from the broadcast channel reception data (step S25), and a propagation loss is calculated from the transmission power value and the measured reception level (step S26). The detected station list related to the base station apparatus is updated with the detected base station scrambling code, timing and propagation loss of the detected base station apparatus (step S27). The operations from step S22 to step S27 described above are performed for all base station apparatuses in the detected station list (steps S28 and S29). That is, until the last position in the detected station list (step S28), the pointer is incremented by one and the above processing (step S22 to step S27) is performed (step S29).
[0071]
After such processing (steps S22 to S27) is performed up to the base station apparatus located at the end of the detection station list (step S28), the list is reranked (reordered) in order of increasing propagation loss (step S30). ), The base station apparatus with the smallest propagation loss is set as the parent station, the gain is determined from the propagation loss of the parent station (step S31), and the radio relay amplification unit 11 is controlled by the gain (step S32).
[0072]
Next, in the wireless relay amplification device of this example, it is searched whether there is a reception signal (reception path) from a base station device other than the base station device currently on the detection station list.
First, a pointer is set at the base station apparatus located at the head of the detection station list (step S33). The search unit 3 is activated in the other station search mode based on the base station scrambling code and timing of the station (base station apparatus) indicated by the pointer (step S34), and the base station scrambling code and timing of the other station are detected (step S35). ). The operation of the search unit 3 in the other station search mode is as described above.
[0073]
Information such as the detected base station scrambling code and timing of the other station is added to the last part of the detected station list (step S36). The operations from the process of step S34 to the process of step S36 described above are performed for all base station apparatuses in the detected station list before the other station detection (step S37, step S38). That is, until the last position in the detected station list before adding another station (step S37), the pointer is incremented by 1 and the above processing (step S34 to step S36) is performed (step S38). If there is another station to be detected, information on the other station detected by the other station detection is added to the detected station list.
[0074]
When the other station detection as described above is completed (step S37), the operation flow returns to the process of step S21 described above and repeats the process in the same steady state as described above. In this way, while increasing the number of master station candidates by detecting other stations, the radio relay amplification unit 11 is controlled so that the base station apparatus with the smallest propagation loss is always the master station.
[0075]
As described above, in the wireless relay amplifying apparatus of this example, for example, when it is used in a mobile communication system that performs wireless communication using the DS-CDMA system shown in the above-described conventional example, the detection station list is stored for the base station apparatus. Prepared, holding the propagation loss of received signals from a plurality of base station devices in the detected station list, and increasing the number of candidates to become the master station by detecting other stations, the propagation loss always the most based on the detected station list By setting the gain of wireless relay amplification of downlink signals and uplink signals so that a small base station apparatus becomes a master station, for example, an increase in interference due to over-amplification can be prevented, and scrambling of the base station apparatus Code relocation can be handled immediately.
[0076]
In addition, in the wireless relay amplification apparatus of this example, any one of the reception paths from the base station apparatus (target station) that is the target of gain control is set as a pilot path, and an arbitrary range before and after the pilot path is windowed. The path detection is performed by regarding the path received in the range outside the window as the path received from the base station apparatus other than the target station. As described above, in the wireless relay amplifying apparatus of this example, when other station detection is performed, a path that is regarded as a path from the target station (parent station) is canceled by providing the above-described window, and the other station candidate path is cancelled. Can be narrowed down, for example, simplifying the process of detecting other stations, reducing the time required for path detection of other stations, and reducing station misauthorization (misauthorization of base station equipment) Can do.
[0077]
In this example, the case where the path detection method to which the present invention is applied is applied to the gain control of the wireless relay amplifying device is shown. However, such a path detection method is used by a mobile station device such as a wireless portable device, for example. The present invention can also be applied to processing such as a path search for searching for a base station device to be communicated. In such a path search in a mobile station apparatus, for example, a plurality of paths are detected from a spread spectrum received signal by a path detection method to which the present invention is applied, and a reference path is selected from the detected paths. By performing path detection processing that does not detect a path within a certain range near the selected reference path, for example, a base station apparatus that is optimal as a communication target that minimizes propagation loss is searched. . Here, the path search can be applied to, for example, an initial path search performed when the mobile station apparatus is activated or a path search performed at the time of handover, for example.
[0078]
In this example, one base station apparatus is used as a master station, a window is provided based on one received signal (pilot path signal) from the parent station, and received signals from other stations are provided outside the window. Although the aspect which detected was shown, as another aspect, for example, providing a plurality of windows on the basis of each of a plurality of path signals from the same base station apparatus, for example, receiving signals from a plurality of different base station apparatuses By providing multiple windows with each as a reference, for example, increasing the reference signal for setting the window as a received signal from a new base station device is detected, etc. It is also possible to use a mode in which received signals from other stations are detected outside the window (that is, the range excluding the inner part of all windows), thereby making the other station detection more efficient. Can .
[0079]
Here, in this example, a wireless relay amplification device is used as the wireless communication device, and a base station device is used as the communication station device.
Further, in this example, the other station signal detection means is provided by the function of detecting the path of the received signal from the base station apparatus (other station) different from the base station apparatus (parent station) as a reference by the other station detection processing unit 25 or the like. Is configured.
[0080]
Further, in this example, a predetermined time width including a reception timing of a signal wirelessly transmitted from a base station apparatus serving as a reference is configured by the above-described window, and a pilot path signal from the above-described master station Thus, a signal from the reference base station apparatus received at the reception timing included in the predetermined time width (that is, a signal wirelessly transmitted from the reference base station apparatus) is configured.
In this example, since a communication environment in which multipath occurs is assumed as a general communication environment, the predetermined time width is set based on any one path signal (pilot path signal) from the reference base station apparatus. Then, a path signal is detected for each path signal from another station.
[0081]
In this example, for example, a broadcast channel spread signal is spread using a product of a broadcast channel channelization code common to the system and a scrambling code unique to each base station device as a spread code. Has been.
Further, in this example, the reception timing detecting means is configured by the function of detecting the reception timing of the signal from the other station in the above-described other station search mode, and the scrambling code of the other station is configured in the above-mentioned other station search mode. The communication station apparatus identification signal detection means is configured by the function of detecting a signal from the other station in a state where the signal is identified.
[0082]
Further, in the wireless relay amplification device of this example, the base station with the smallest propagation loss of the received signal among all the base station devices that have detected the reception path, including other stations that have detected the reception path in the other station search mode. The relay amplification gain control means is configured by the function of controlling the gain of relay amplification of downlink signals and uplink signals corresponding to the station apparatus.
[0083]
Here, the configuration of the wireless communication apparatus according to the present invention is not necessarily limited to the above-described configuration, and various configurations may be used.
The application field of the present invention is not necessarily limited to the above-described fields, and the present invention can be applied to various fields.
[0084]
Further, as various processes performed in the wireless communication apparatus according to the present invention, for example, the processor executes a control program stored in a ROM (Read Only Memory) in a hardware resource including a processor, a memory, and the like. A controlled configuration may be used, and for example, each functional unit for executing the processing may be configured as an independent hardware circuit.
Further, the present invention can be grasped as a computer-readable recording medium such as a floppy (registered trademark) disk or a CD (Compact Disc) -ROM storing the control program, or the program (itself). The processing according to the present invention can be performed by inputting a program from a recording medium to a computer and causing the processor to execute the program.
[0085]
【The invention's effect】
As described above, according to the wireless communication apparatus according to the present invention, when detecting a signal transmitted from a communication station apparatus other than the reference communication station apparatus and received by the wireless communication apparatus, the reference communication station A signal received by wireless transmission from a communication station apparatus other than the reference communication station apparatus is detected from signals received at a timing outside a predetermined time width including a reception timing of a signal wirelessly transmitted from the apparatus. Therefore, for example, the time required for the detection is shortened compared to the case of detecting a signal received and transmitted wirelessly from a communication station apparatus other than the reference communication station apparatus from among signals received at all timings as in the prior art. be able to.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of a wireless relay amplification apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a broadcast channel, a synchronization channel, and an MF output.
FIG. 3 is a diagram illustrating an example of a broadcast channel and an MF output of a preceding wave and a delayed wave.
FIG. 4 is a diagram illustrating an example of an MF output when a multiplexed wave of a synchronization channel is received.
FIG. 5 is a diagram showing an example of a detected station list.
FIG. 6 is a diagram illustrating an example of an operation performed by the wireless relay amplification device in an initial state.
FIG. 7 is a diagram illustrating an example of an operation performed by the wireless relay amplification device in a steady state.
FIG. 8 is a diagram illustrating an example of a wireless relay amplification device according to a conventional example.
[Explanation of symbols]
1 .... Radio demodulation unit, 2 .... A / D conversion unit, 3 .... Search unit,
4. Despreading unit 5. Baseband demodulation unit 6. Broadcast information analysis unit
7 ・ ・ Reception level measurement unit, 8 ・ Propagation loss calculation unit,
9 .. Detection station list holding unit, 10... Gain setting unit,
11 .. Wireless relay amplification unit 21 .. Search control unit 22 .. Path detection unit
23 .. Timing generation unit 24.. Code identification unit
25 .. Other station detection processing section,

Claims (4)

A wireless communication device that detects a signal that is wirelessly transmitted and received from a communication station device other than a reference communication station device,
A wireless communication device used in a mobile communication system using a CDMA system,
Wireless communication using slots,
Setting a predetermined time width in the time width of one slot including the reception timing of the radio transmitted signal from a communication station serving as a reference, and of the predetermined comprising at in the time width of the one slot wireless communication device comprising the other station signal detecting means for detecting a signal received wirelessly transmitted from a communication station other than the reference communication station from the signal received outside of the time duration . The wireless communication device according to claim 1,
The other-station signal detection means, when a signal wirelessly transmitted from a reference communication station apparatus is received as a plurality of path signals arriving via a plurality of paths, one of the plurality of path signals. The predetermined time width is set on the basis of one path signal, and signals wirelessly transmitted from communication station apparatuses other than the reference communication station apparatus are received as a plurality of path signals arriving via a plurality of paths. In this case, a path signal is detected for each path signal.
A wireless communication apparatus. The wireless communication device according to claim 1 or 2,
A spread signal spread using a product of a channelization code common to the system and a scrambling code unique to each communication station device is wirelessly transmitted from the communication station device,
The other-station signal detection means of the wireless communication device includes a reception timing detection means for detecting a reception timing of the spread signal using a channelization code, and a reference signal from among the spread signals received at a timing outside the predetermined time width. A communication station apparatus identification signal detecting means for detecting a spread signal received by radio transmission from the communication station apparatus using a scrambling code corresponding to a communication station apparatus other than the communication station apparatus,
A wireless communication apparatus. The wireless communication apparatus according to any one of claims 1 to 3,
A wireless relay amplification device that relays and amplifies signals communicated between a base station device and a mobile station device,
The other station signal detection means detects a signal received by radio transmission from a base station apparatus other than the base station apparatus serving as a reference,
Among all the base station devices that have detected the received signal, including the base station device that has detected the received signal by the other station signal detecting means, the relay amplification of the relay amplification is performed corresponding to the base station device having the smallest propagation loss of the received signal. Comprising a relay amplification gain control means for controlling the gain;
A wireless communication apparatus.

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