JP3647986B2 - Wireless communication device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radio communication system in a mobile communication system composed of a plurality of radio zones, and in particular, a radio communication apparatus serving as a mobile station minimizes the influence of reception level fluctuations from a plurality of base stations. The present invention relates to a wireless communication system for selecting a base station.
[0002]
[Prior art]
In a general mobile communication system based on the small zone method, a plurality of base stations arranges a plurality of radio zones two-dimensionally or three-dimensionally, and one radio zone is composed of one base station. FIG. 13 is a diagram showing the relationship between the base station, the radio zone of the base station, and the mobile station, and shows a case where the base stations BS1, BS2, BS3, and BS4 are in the vicinity of the mobile station PS. A circle indicates a radio zone, a solid circle SE1 is a radio zone of the base station BS1, a dotted circle SE2 is a radio zone of the base station BS2, a dashed circle SE3 is a radio zone of the base station BS3, and a dashed-dotted circle SE4 is a radio zone of the base station BS4. In the figure, the wireless zone is indicated by a circle, but the actual wireless zone has a complicated shape due to buildings, topography, and the like. There are a plurality of mobile stations in the radio zone. In general, the radio zone of one base station overlaps the radio zones of neighboring base stations, and a mobile station selects one base pole from many base stations to perform communication.
[0003]
In such mobile communication, the wireless communication system in the mobile station as described in the literature (Japanese Patent Laid-Open No. 3-226127) in the mobile station or base station is configured as shown in FIG. Take.
In FIG. 12, 1 is a transmission / reception unit that processes a received signal from an antenna (not shown), and 2 is a base that processes a baseband from the transmission / reception unit 1 and converts data into a baseband signal. A band processing unit 3 is a reception level detection unit that detects the magnitude of the baseband signal from the transmission / reception unit 1.
[0004]
The reception level detection of the mobile station is performed by measuring the reception level of the control channel transmitted by each base station. The control channel is a common channel used by separating the frequency and time so that each base station does not overlap with signals from other base stations. The frequency for this control channel is determined in advance, but the number of channels is small, and each base station uses the time divided on the time axis so that the transmission signals do not overlap. The control channel includes information such as a number unique to the base station and a frequency for communicating with the base station.
[0005]
When a mobile station selects a base station when power is turned on or when a base station is switched, the mobile station searches for all the base stations that can receive the reception level obtained from the reception level detection unit 3, and the baseband processing unit 2 receives the most. A strong base station was selected.
[0006]
For example, in FIG. 13, the reception levels of the base stations BS1 to BS4 at the position of the mobile station PS are set to P₁, P₂, P_Three, P_FourAnd the size of the reception level is P₁> P_Four> P₂> P_ThreeSuppose that When the mobile station PS selects a base station, there is a high probability of selecting the base station BS1 with the highest reception level. However, if there is a passage between the mobile station PS and the base station BS1, the line-of-sight propagation path is shielded by a person or a vehicle moving along the passage. While the mobile station PS and the base station BS1 are communicating, if the reception level fluctuates because the line-of-sight propagation path is blocked, the mobile station PS performs channel switching (intra-cell handoff) or base station switching (out-cell handoff). When the mobile station PS selects the base station BS4 with the next highest reception level by switching the base station, there is still a path between the mobile station PS and the base station BS4, so there is a need for channel switching or base station switching again. Arise.
[0007]
[Problems to be solved by the invention]
In the conventional wireless communication system, the mobile station selects the base station with the strongest reception level when power is turned on or when the base station is switched. However, if the mobile station is stationary and performs wireless communication around a place such as a passage where there is a lot of human movement, if the base station having the strongest reception level is selected, there is a high probability of receiving level fluctuations.
[0008]
If the mobile station selects a base station that has a high probability of receiving reception level fluctuations even if the reception level is high, channel quality is attempted to be ensured by channel switching or base station switching. However, in order for a mobile station to avoid reception level fluctuations by channel switching, it is only possible to select a channel with a low interference wave level, so the probability that the influence of reception level fluctuations can be avoided by channel switching is low.
[0009]
In addition, if the channel quality cannot be satisfied with all channels of the base station with which communication is performed, the mobile station switches the base station, but the base with the highest reception level among all base stations other than the base station used. Even if a station is selected, there is no guarantee that the base station is not affected by fluctuations in the reception level, so channel switching and base station switching are repeated again.
[0010]
When a base station with the strongest reception level is selected in this way, a mobile station in a position that is easily affected by fluctuations in reception level may select a base station that is affected. If received, not only frequent channel switching and base station switching are performed, but traffic on the control channel is increased, leading to call loss and forced disconnection.
[0011]
The present invention solves the above-mentioned conventional problems, selects a base station that is not affected by fluctuations in reception level, and reduces channel switching, base station switching, control channel traffic volume, call loss, and forced disconnection. The goal is to provide stable line quality.
[0012]
[Means for Solving the Problems]
In order to solve the above-described problems and achieve the object, a wireless communication apparatus according to claim 1 is a communication system including a plurality of wireless base stations and wireless communication apparatuses (mobile stations). Reception quality measuring means for measuring the reception quality of base stations around the wireless communication device, and quality information creating means for creating quality information of each base station from the reception quality of the base station measured by the reception quality measuring means; Base station selection means for selecting a base station based on the created quality information of the base station, wherein the quality information creation means includes a reception level measured as the reception quality and a reception level measured in the past. The difference from the maximum value of the level is obtained, the number of times that the difference becomes larger than a specific threshold value is counted, the presence / absence of reception level fluctuation is determined based on the counted number, and it is received as the quality information. And wherein the creating information as to whether or level variations.
[0013]
According to a second aspect of the present invention, there is provided a radio communication apparatus including a plurality of radio base stations and a radio communication apparatus (mobile station), wherein the radio communication apparatus receives reception quality of base stations around the radio communication apparatus. Based on reception quality measurement means for measuring quality information creation means for creating quality information of each base station from reception quality of the base station measured by the reception quality measurement means, and quality information of the created base station Base station selection means for selecting a base station, wherein the reception quality measurement means obtains a difference between a reception level measured as the reception quality and an average value of reception levels measured in the past, and the difference Counts the number of times that exceeds a specific threshold, determines the presence / absence of reception level fluctuation based on the number of counts, and creates information about the presence / absence of reception level fluctuation as the quality information It is characterized in.
[0014]
According to a third aspect of the present invention, in the wireless communication device according to the first or second aspect, the quality information creating means attaches priority information based on the quality state to the created quality information. And
[0015]
According to a fourth aspect of the present invention, in the wireless communication apparatus according to the third aspect, the base station selecting means selects the base station based on the priority information attached to the quality information. To do.
[0016]
  Also,Claim 5TakeThe wireless communication device is claimed in claim 1.From4Any one ofDescriptionNoIn the line communication device, the quality information creating means updates the quality information.
[0017]
  Also,Claim 6TakeA wireless communication device is claimedTo 5DescriptionNoIn the line communication apparatus, the quality information is updated periodically or according to a change in the reception environment.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a wireless communication apparatus (hereinafter referred to as a mobile station) showing Embodiment 1 of the present invention. 1 is a transmission / reception unit, 2 is a baseband processing unit that processes baseband signals or transmission data received by the transmission / reception unit 1, and 4 is a reception level of a control channel of the base station, and reception quality of the reception level is measured. The reception level fluctuation detection unit 5 is a base station selection unit that creates base station quality information and selects a base station from the reception quality measured by the reception level fluctuation detection unit 4.
[0020]
  Next, the operation will be described with reference to FIGS.
  First, the relationship between the mobile station and the base station is as shown in FIG. That is, the base station BS1, the base station BS2, the base station BS3, the base station BS4, and the mobile station PS are configured, and each base station overlaps the radio zone. Then, the mobile station PS measures the reception level of the control channel of the base station, and the magnitude of the measured reception level of the control channel (hereinafter simply referred to as reception level) is also P.₁> P_Four>P ₂ >P _Three And It is considered that the mobile station PS in such a radio zone selects an optimal base station in which the reception level fluctuation hardly occurs in the line-of-sight propagation path with each base station and its surroundings.
[0021]
For example, the mobile station PS is closest to the base station BS1 and has a high reception level. However, when there is a passage between the mobile station PS and the base station BS1, the reception level fluctuates due to movement of people or cars. Similarly, there are passages in the line-of-sight propagation path between the mobile station PS and the base station BS4, and the reception level fluctuates due to the movement of people or cars. When the mobile station PS selects the base station BS1 or the base station BS4, the mobile station PS recognizes that the influence of the reception level fluctuation occurs, and selects either the base station BS2 or the base station BS3.
[0022]
The configuration of the mobile station PS is shown in FIG. A reception signal a from an antenna (not shown) is demodulated by the transmission / reception unit 1 and output as a baseband signal b. This baseband signal b is input to the baseband processing unit 2 and also to the level fluctuation detection unit 4. The reception level fluctuation detection unit 4 measures the reception level of the input baseband signal b according to the measurement target base station timing signal c from the baseband processing unit 2. Store the measured reception level value. The reception level measurement is performed a plurality of times during a predetermined period, and the maximum value of the reception level is obtained. Next, the probability of level fluctuation is obtained from the maximum reception level and the reception level, and when it is equal to or greater than a predetermined value, “level fluctuation is present”, and when it is equal to or smaller than the predetermined value, “level fluctuation is not present”. Is output. Further, the reception level detection unit 4 outputs the reception level information c to the baseband processing unit 2.
[0023]
Similarly, the reception level and the presence / absence of level fluctuation are measured for other base stations. That is, the reception levels and the presence / absence of level fluctuations at base stations BS1 to BS4 in FIG. At the time of these storages, the received level measured according to the memory write address f and the presence / absence of level fluctuation are stored in association with the identification information of the base station so that it can be understood from which base station the measurement result.
[0024]
  FIG. 2 is a block diagram showing details of the reception level fluctuation detector 4 of the first embodiment. Details of the operation will be described with reference to the drawings. Baseband signalbIs converted by the A / D converter 41 and a reception level value is output. At this time, the counter 44 is advanced for each measurement, and the number of measurements is counted. The reception level comparator 42 obtains a difference between this level value and the maximum reception level value measured so far and stored in the memory 43. Then, the predetermined threshold value TH1 is compared with the obtained reception level difference, and if it is larger than the threshold value TH1, the counter 45 is advanced as one reception level fluctuation.
  If the reception level is larger than the maximum reception level measured before being read from the memory 43 in this reception level comparison, it is written in the memory 43 as a new maximum reception level value, and the maximum reception level is updated. .
  Next, in the determination circuit 46, the reception level fluctuation probability is calculated from the count value A (the number of times of measurement) of the counter 44 stored in the memory 43 and the value (B) of the counter 45 stored in the memory 43 by the following equation. Ask.
          Reception level fluctuation probability = B / A
  Then, the obtained reception level fluctuation probability is compared with a predetermined threshold value TH2, and when the reception level fluctuation probability is greater than the threshold value TH2, it is determined that there is a reception level fluctuation, and reception When the level fluctuation probability is smaller than the threshold value TH2, it is determined that the reception level fluctuation is “none”, and the determination result is stored in the memory in association with the measured base station.
[0025]
In the level fluctuation detection unit, the reception level fluctuation probability is obtained from the difference between the maximum reception level and the reception level, but the average value of the reception levels is obtained from the reception level for each reception level measurement as shown in FIG. The reception level fluctuation probability may be obtained from the value and the reception level.
Hereinafter, the operation of the reception level fluctuation detector 4 in FIG. 3 will be described in detail. FIG. 7 is a flowchart showing an operation flow. In the figure, S11,... Indicate steps or procedures (the same applies to the following flowcharts).
The input baseband signal b is converted into a level value by the A / D converter 41. The reception level value is compared with the reception level average value obtained during the measurement period read from the memory 43 by the reception level comparison circuit 42, and a reception level fluctuation range (difference) is obtained (S11). Further, the value of the counter 44 is advanced by 1, and the count value (A) is stored in the memory 43 as the number of measurements. When this difference is compared with a predetermined threshold value TH1 and greater than the threshold value, the value of the counter 45 is advanced. The count value (B) of the counter 45 is stored in the memory 43 as the reception level fluctuation count. When the reception level difference is smaller than the threshold value, the running average is calculated from the reception level in the averaging circuit 46, the reception level average value read from the memory 43, and the count values of the counters 44 and 45 stored in the memory 43. Is obtained by the following equation, stored in the memory 43, and the average value of the reception level is updated.
{Reception level average value × (A−B−1) + reception level} / (A−B)
The updated reception level average value is used as the reception level average value at the next reception level measurement.
[0026]
In the determination circuit 46, the reception level fluctuation probability is obtained by the following equation from the count values A and B stored in the memory 43 and a predetermined threshold value TH2.
Reception level fluctuation probability = B / A
The reception level fluctuation probability is compared with a predetermined threshold value TH2 (S12). When the reception level fluctuation probability is larger than the threshold value TH2, the reception level fluctuation is “present” (S13), and the threshold value TH2 When it is smaller, it is determined that the reception level variation is “none” (S14), and is output as a signal g indicating whether or not the reception level varies.
The determination result is stored in association with the measured base station.
[0027]
Here, an example of the set values of the threshold value TH1 and the threshold value TH2 is shown in FIG. The figure shows a probability distribution of reception level fluctuation when an omnidirectional antenna is used as a mobile station reception antenna. The horizontal axis represents the reception level normalized by the average reception level obtained by averaging the reception levels in the measurement data, and the vertical axis represents the cumulative probability below the horizontal axis. The threshold value TH1 corresponds to the horizontal axis, the threshold value TH2 corresponds to the vertical axis, and the threshold value TH1 and the threshold value TH2 correspond to one to one.
[0028]
Next, the operation of the base station selection unit 5 will be described. The base station selection unit 5 notifies the level variation detection unit 4 of the memory address f corresponding to the identification information (ID) unique to the base station obtained from the baseband processing unit 4, and results of detecting the reception level variation described above The base station priority is determined from the maximum reception level or the average reception level, and the base station priority and the base station timing information obtained from the baseband processing unit 2 are associated with the ID and stored for each base station. To do. When there is a base station assignment request d from the baseband processing unit 2, the base station information d of the base station having a high priority is notified from the created table (50 in FIGS. 5 and 6).
When the base station selection unit 5 has a priority database, the base station is selected according to the priority of the priority database. An example of creating a base station priority database is shown below.
[0029]
The base station priority database includes a selection group 1 and a selection group 2 as shown in FIGS.
The mobile station base station by sweeping the reception frequency of the control channel when the power is turned on or at the end of movement (when it is possible to confirm whether the mobile station is moving or stationary using some movement detection means) Measure the reception level. All measured base station reception levels are assigned to selection group 1 and rearranged so that the priority of the base station with the highest reception level is the highest. For example, in FIG. 13, the base station with the highest reception level seen from the mobile station PS is BS1. In the following order, BS4, BS2, and BS3. Since the mobile station PS first assigns all base stations to the selection group 1 in descending order of reception level, priority information as shown in FIG. 5 is created.
[0030]
The mobile station PS monitors the reception level fluctuation of each base station, and when there is a reception level fluctuation, the base station assigned to the selection group 1 is assigned to the selection group 2. In the case of base stations BS1 and BS4 in FIG. 13, since the mobile station and the path are sandwiched, reception level fluctuations due to reception level fluctuations occur. Accordingly, base station BS1 and base station BS4 are assigned to selection group 2. In the selection group 1, the base station BS2 and the base station BS3 remain. However, since priority is given to the remaining base stations in order from the highest reception level, the base station BS2 has the highest priority. Since the base station of the selection group 2 also increases the priority of the base station having a high reception level, the priority of the base station BS1 is higher than that of the base station BS4.
[0031]
FIG. 8 is a flowchart showing a procedure for creating a base station priority database.
When the mobile station PS selects a base station, the channels are checked in order of priority from the base stations of the selection group 1, and there is no base station having a free channel in the selection group 1 or a base station having a channel satisfying the channel quality. In this case, the selection is made from the selection group 2 according to the priority.
That is, the priority viewed from the mobile station side of selection group 2 is (number of base stations in selection group 1 + priority of selection group 2).
[0032]
The mobile station PS detects the reception level of the receivable base station, searches for all control channels satisfying the required reception level (S21), sorts in descending order of reception level, and selects group 1 of the base station priority database. All base stations are assigned to (S22).
[0033]
After assigning a base station to selection group 1 in S22, the base station with the highest priority is selected from the base stations recorded in selection group 1 (S23).
[0034]
After selecting the base station with the highest reception level, the presence / absence of a call / incoming call is confirmed (S24). If there is no call / incoming call, the reception level fluctuation of the selected base station is monitored (S25). If there is, the base station used is assigned to the selection group 2 (S26), and the base station with the second highest priority is selected after the base station used (S27).
[0035]
If there is no reception level fluctuation in the confirmation of presence / absence of reception level fluctuation in S25, that is, if the reception level fluctuation detecting means determines that the influence of the reception level fluctuation is small, the base station used is left in the selection group 1 and used. The base station with the next highest priority is selected after the base station that has been set (S27).
[0036]
When all the base stations are selected in step S28, the base station priority group creation ends. If not all base stations have been selected, the process returns to S24 and the procedure is repeated.
[0037]
If there is an outgoing call / incoming call in the confirmation of the presence / absence of outgoing / incoming call in S24, the base station priority group creation is interrupted, and the identification information ID of the searched base station is held (S29). In order to deal with outgoing / incoming calls, it is checked whether there is a base station in selection group 1 (S30). If there is a base station in selection group 1, the base station with the highest priority is selected from selection group 1 ( S31) When the presence / absence of the base station of the selection group 1 in S30 is confirmed, if the base station of the selection group 1 does not exist, the base station with the highest priority is selected from the selection group 2 (S32).
[0038]
Next, it is confirmed whether or not the call is ended (S33). If it is not determined that the call is ended, the base station priority group creation is suspended until the call is ended, and if it is determined that the call is ended, the base held in S29 is held. A station is selected and base station priority group creation starts (S34).
[0039]
FIG. 9 is a flowchart showing an operation procedure in which the mobile station PS selects a base station for a call. When the mobile station selects a base station, it is checked whether there is a base station having an empty channel in the selection group 1 (S41), and if it exists, the base station is selected from the selection group 1 according to the base station priority. (S42).
[0040]
It is confirmed whether or not channel assignment has been performed at the selected base station (S43). If assignment has been completed, the base station assignment is terminated. If channel assignment is not performed, the process returns to S41 and the procedure is repeated.
[0041]
Further, in the confirmation of whether or not there is a base station having an empty channel in the selection group 1 in S41, if there is no base station having an empty channel, an available base station is selected from the selection group 2 It is determined whether there is (S44). If there is no base station having an empty channel, it is treated as a call loss (S45). If there is a base station having an empty channel, the base station is selected from the selection group 2 according to the priority (S46), and it is confirmed whether or not channel assignment has been completed in the selected base station (S43).
[0042]
FIG. 10 is a flowchart showing a data update operation after the creation of the base station priority database is completed. When the mobile station selects a base station in the selection group 1, the reception level fluctuation detection unit 4 monitors the reception level of the selected base station. When it is determined that there is a fluctuation in the reception level, the base station selection unit 5 selects the base station. Update priority data. When the mobile station selects a base station from the selection group 2, the base station priority database is not updated.
[0043]
The database update operation will be described below with reference to FIG. After completing the creation of the base station priority database, the mobile station selects the base station with the highest priority from the selection group 1 according to the base station priority database, and then the reception level fluctuation detector 4 receives the reception level of the selected base station. The fluctuation is monitored (S51). When the reception level fluctuation is detected, the base station used is moved to the selection group 2, and the base stations of the selection group 1 and the selection group 2 are reassigned priorities in the descending order of the reception level to update the data ( S52).
[0044]
Next, after updating the data, it is confirmed whether the base station is registered in the selection group 1 (S53). If there is no registered base station, the base station is selected from the selection group 2 according to the base station priority database. Select (S55). The update of the base station priority database is terminated. When there is a base station registered in the selection group 1 in the confirmation of the existence of the base station in the selection group 1 in S53, the base station with the highest priority is selected from the selection group 1 (S54), and the process returns to S51 again. Monitor reception level fluctuations.
[0045]
FIG. 11 is a flowchart illustrating a procedure of a base station selection operation in which a mobile station PS does not have a base station priority database and selects a base station that varies in reception level.
This operation will be described with reference to the drawings. The mobile station PS detects the reception levels of all receivable base stations, and selects the base stations in descending order of the base station reception level (S61). The reception level fluctuation is detected and the presence / absence of the reception level fluctuation is confirmed (S62). If reception level fluctuation is detected, it is determined whether all receivable base stations have been searched (S64). If all the base stations have not been searched yet, the procedure returns to step S61 and the procedure is repeated.
If it is determined in the search confirmation of all the base stations in step S64 that all the base stations have been searched, the base station having the strongest reception level is selected from all the receivable base stations (S65), and the channel allocation is performed. Is confirmed (S66), channel assignment is performed, and the process ends. If no channel assignment is made, it is processed as a call loss (S67).
[0046]
In step S61, the base stations are selected in descending order of reception level. However, the base stations may be selected in the order in which the mobile station supplements the base stations.
[0047]
If no reception level fluctuation is detected in the reception level fluctuation detection confirmation in S62, it is confirmed whether or not channel allocation is possible (S63), channel assignment is performed, and base station selection is terminated. If channel allocation is not performed in the confirmation of whether channel allocation is possible in S63, the process returns to S61 and is repeated.
[0048]
【The invention's effect】
As described above, the present invention has the reception level fluctuation detecting means and the base station selection means of the control channel of the base station. Since the reception quality information is provided, it is possible to preferentially select a base station with little reception level fluctuation and to perform communication, and there is an effect of reducing channel switching and base station switching due to the influence of reception level fluctuation.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a wireless communication apparatus according to the present invention.
FIG. 2 is a block diagram showing a configuration of a reception level fluctuation detection unit of the present invention.
FIG. 3 is a block diagram showing a configuration of another reception level variation detector of the present invention.
FIG. 4 is a diagram illustrating a threshold setting example of a reception level fluctuation detection unit.
FIG. 5 is a diagram showing a priority data map of a base station selection unit according to the present invention.
FIG. 6 is a diagram showing another priority data map of the base station selection unit of the present invention.
FIG. 7 is a flowchart showing an operation flow of a level fluctuation detection unit of the present invention.
FIG. 8 is a flowchart showing a priority database creation procedure according to the present invention.
FIG. 9 is a flowchart showing a base station selection operation according to the present invention.
FIG. 10 is a flowchart showing a priority database update process according to the present invention.
FIG. 11 is a flowchart showing another example of the base station selection operation of the present invention.
FIG. 12 is a block diagram showing a configuration of a conventional wireless communication apparatus.
FIG. 13 is a diagram illustrating a relationship between a mobile station, a base station, and a radio zone of the base station.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Transmission / reception part, 2 Baseband process part, 4 Reception level fluctuation | variation detection part, 41 A / D converter, 42 Reception level comparison part, 43 Memory, 44, 45 counter, 46 Judgment circuit, 47 Averaging circuit, 5 Base station Selection part.

Claims (6)

In a communication system composed of a plurality of wireless base stations and wireless communication devices (mobile stations),
The wireless communication device is
A reception quality measuring section that measures reception quality of the base station near the wireless communication device,
And quality information creation means for creating a quality information receiving product quality or we each base station of the base station measured by the reception quality measuring means,
Base station selecting means for selecting a base station based on the created base station quality information ;
Equipped with a,
The quality information creation means obtains a difference between the reception level measured as the reception quality and the maximum value of the reception level measured in the past, and counts the number of times that the difference is greater than a specific threshold value, determining whether the receive level variation based on the count, creation to radio communications device you wherein Rukoto the information as to whether or not the reception level fluctuation as the quality information. In a communication system composed of a plurality of wireless base stations and wireless communication devices (mobile stations),
  The wireless communication device is
  Reception quality measuring means for measuring reception quality of base stations around the wireless communication device; and
  Quality information creating means for creating quality information of each base station from the reception quality of the base station measured by the reception quality measuring means;
  Base station selecting means for selecting a base station based on the created base station quality information;
  With
  The reception quality measuring means calculates a difference between the reception level measured as the reception quality and an average value of the reception levels measured in the past, and counts the number of times that the difference becomes larger than a specific threshold value, A wireless communication apparatus that judges whether or not there is a reception level fluctuation based on the count number, and creates information about the presence or absence of a reception level fluctuation as the quality information. The quality information creation means, the wireless communication apparatus according to claim 1 or 2, characterized in that prioritizing information based on the state of quality to the created quality information. The radio communication apparatus according to claim 3, wherein the base station selection unit selects a base station based on priority information attached to the quality information. The quality information creation means, the wireless communication apparatus according to any one of claims 1, characterized in that updating the quality information 4. The wireless communication apparatus according to claim 5, wherein the update is performed periodically or according to a change in reception environment.

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