• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The present invention relates to a method for setting a reserved channel of a mobile communication base station that can adaptively set a reserved channel of an appropriate size using a fuzzy logic controller to cope with a fluid handoff traffic volume. Sampling the size (quantity) of the handoff calls to a fuzzy logic controller at a predetermined time interval and outputting the control volume at a predetermined time interval according to the size (quantity) of the handoff calls from the fuzzy logic controller. And setting, by the base station signal processor, the reserved channels adjusted by the control volume in the current reserved channel to the traffic channel element and feeding back to the fuzzy logic controller for adjusting the reserved channel for the traffic volume of the handoff call to be sampled after a certain time. By selecting the reserved channel according to the traffic density of the handoff call Adjust with
    公开号:KR19990043748A
    申请号:KR1019970064790
    申请日:1997-11-29
    公开日:1999-06-15
    发明作者:고유창
    申请人:서평원；엘지정보통신 주식회사；
    IPC主号:
    专利说明:

    How to set reserved channel of mobile communication base station
    BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station channel setting method of a mobile communication system. In particular, a fuzzy logic controller can adaptively set a reservation channel of an appropriate size to cope with the amount of handoff traffic. The present invention relates to a reserved channel setting method of a mobile communication base station.
    In general, in the mobile communication system, the handoff traffic density is proportional to the user's movement according to the region, and even in the same area, the handoff traffic density changes every hour. In the conventional base station handoff reserved channel setting method, as shown in FIG. 1, a base station signal processor (BSP: BTS Signaling Processor) serving as a top processor and resource management role in a base station includes all available traffic channel elements. Among the (TCE: Traffic Channel Elements), about 30% of channel elements are fixedly set as reserved channels for handoff, and handoff call processing of reserved channels is performed. Initiating calls and handoff calls within normal channels 1, 2, ..., i receive call service. After that, if the normal channels (1, 2, ..., i) are all in use, they are serviced in the reserved channels (i + 1, ..., n) fixedly set only for the handoff calls. This method has a disadvantage in that the reservation channels are always fixed and thus cannot actively cope with the amount of handoff traffic that varies due to various causes.
    Referring to FIG. 2, a conventional base station handoff reserved channel setting method is described with reference to FIG. 2. When a handoff call arrives (21), first, a handoff call is determined whether a normal channel is available (22), and a channel is allocated if available. Otherwise, it is determined if the reserved channel is available (23). At this time, if the reserved channel is available, the channel is allocated using the reserved channel (24). If the reserved channel is not available, the call is forced to connect to the terminal (25).
    According to the conventional method, since the handoff reservation channel is fixedly operated, it is difficult to efficiently cope with the changing handoff traffic density. Therefore, when there are more reserved channels set than the current handoff traffic density, waste of limited channel resources is avoided. In the opposite situation, there is a problem that the handoff failure increases, thereby degrading system performance and reliability.
    The present invention has been made in view of the above-mentioned problems of the prior art, and is a reserved channel of a mobile communication base station that can adaptively set a reserved channel of an appropriate size using a fuzzy logic controller to cope with the amount of handoff traffic. The purpose is to provide a setting method.
    1 is a view for explaining a conventional base station handoff reserved channel setting method;
    2 is a flowchart illustrating a conventional method for setting a base station handoff reserved channel;
    3 is a view for explaining a base station handoff reserved channel setting method of the present invention;
    4 is a flowchart illustrating a method for establishing a base station handoff reserved channel according to the present invention in order;
    5 is a block diagram of a fuzzy logic controller according to the present invention;
    6A to 6C are diagrams illustrating membership functions used in the fuzzy logic controller according to the present invention, respectively.
    7 is a view showing a fuzzy rule base used in the fuzzy logic controller according to the present invention.
    *** Explanation of symbols for main parts of drawing ***
    50: Fuzzy Logic Controller 51: Diffusion Peg Module
    52: fuzzy reference engine 53: fuzzy placement module
    54: fuzzy rule base 55: control processor
    In accordance with an aspect of the present invention, there is provided a method for setting a reserved channel of a mobile communication base station, by sampling a size (quantity) of handoff calls at predetermined time intervals together with a predetermined number of reserved channels to a fuzzy logic controller. The process of inputting, outputting the control volume at regular intervals according to the size (quantity) of the handoff calls in the fuzzy logic controller, and the traffic channel through the reserved channels adjusted by the control volume in the current reserved channel in the base station signal processor It is set to the element and the process of feedback to the fuzzy logic controller for adjusting the reservation channel for the traffic volume of the handoff call to be sampled after a certain time, characterized in that the reserved channel is selectively adjusted according to the traffic density of the handoff call.
    Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.
    3 is a view for explaining a base station handoff reserved channel setting method of the present invention, Figure 4 is a flow chart showing a base station handoff reserved channel setting method according to the present invention in sequence, Figure 5 is a fuzzy logic according to the present invention 6A through 6C are diagrams showing membership functions used in the fuzzy logic controller according to the present invention, and FIG. 7 is a diagram showing a fuzzy rule base used in the fuzzy logic controller according to the present invention.
    Referring to FIG. 3, the base station handoff reserved channel setting scheme according to the present invention is described. In addition to the number of reserved channels previously set, the amount of handoff calls is sampled at a predetermined time ΔT and purged. Input to logic controller FLC. The fuzzy logic controller FLC outputs a control volume of ΔP every ΔT depending on the size of the handoff calls. ΔP is the number of reserved channels to be adjusted to + or-in the currently set reserved channel. The base station signal processor (BSP) sets new reserved channels adjusted in the current reserved channel by ΔP in the traffic channel element (TCE), which in turn controls the reserved channel control for the traffic volume of handoff calls to be sampled after ΔT. To the Forge Logic controller for In this method, since the reserved channel is selectively adjusted according to the traffic density of the handoff call, the handoff call can be more effectively coped with.
    Referring to Fig. 4, the base station handoff reserved channel setting method of the present invention according to the above-described principle, when the handoff call is received (41), the current handoff call sampling of the reserved channel to which the fuzzy logic controller is preset A new reserved channel is established according to the handoff call density over time (42, 43). Here, the handoff call sampling time can be adjusted to several minutes or tens of minutes as necessary. Thus, the newly set number of reserved channels is properly reset by the fuzzy logic controller at the next handoff call sampling time (42). When the adjusted handoff call arrives, the call service is first received in the normal channel (44, 46, 48), and when the normal channel is available, the call service is reserved by the reserved channel (45, 46, 48). ).
    As shown in FIG. 5, the fuzzy logic controller receives two crisp values as an input vector from a fuzzification module 53 as an input vector to the membership function shown in FIGS. 6A and 6B. To linguistic variables. At this time, the two channel inputs are handoff traffic density and the number of reserved channels last set.
    6A shows a membership function for handoff traffic density, which consists of five membership functions. Here, the y-axis represents the membership class of this set by the membership function μ, and the membership function generally takes a value between "0" and "1", i.e. μ → [0,1], where " 1 "means full membership and" 0 "means null membership. The x-axis is also expressed as a percentage of the initial call traffic density from "0" to "1", where the sign "VL" shown in the figure is very low, "L" is low, "M" is medium, and "H" is High, "VH" indicates very high. 6B shows membership functions for the size of the last reserved channel number, and is composed of five membership functions. The y-axis represents the membership class of this set by the membership function (μ) as in FIG. 6A, and the "0" and "6" of the x-axis represent the minimum and maximum number of reserved channels that the fuzzy logic controller can output. will be. Herein, the maximum and minimum number of reserved channels may be defined according to the number of all traffic channels. 6B indicates that "VS" is very small, "S" is small, "M" is medium, "B" is large, and "VB" is very large.
    In FIG. 5, a fuzzy inference engine 52 receives a fuzzy input vector from the fuzzy information module 53 as an input and performs approximate reasoning using a minimum operation. Through the ANDing of the membership functions shown in FIG. 6 for the n-fuzzy variable, that is, through the intersection, the appropriate rule is performed in the basic purge rule of FIG. 7 using the "IF-THEN" rule. In the fuzzy information module 53, the number of control of the reserved channel, which is a control value that is actually controllable by the membership functions for the reserved channel tuning of FIG. 6C, is obtained through the centroid method. Is output. The membership function for the reserved channel tuning consists of nine membership functions. The y-axis represents the membership class of this set by the membership function (μ) as shown in FIG. 6A, and the "-6" and "6" of the x-axis are the maximum and minimum tuning channels for tuning the number of the last reserved channels. It shows the number. The first letters "N" of "NVL", "NL", "NM", and "NS" in this figure indicate negative, "VL" is very low, "L" is low, "M" is medium and "S" is small. Also, the first letters "P" of "PS", "PM", "PL", and "PVL" indicate positive, "S" is small, "M" is medium, and "L" is low. , "VL" indicates very low and "AZ" means zero approximation.
    As an example, if the number of reserved channels currently set in a cell is currently 4, and the handoff request to the cell has a traffic density of 0.3 for the initial call in this cell, then these values are respectively set. Corresponding to membership function, we can get fuzzy input vector like [Table 1] below.
    Membership Function of Handover Traffic SizeMembership function of reserved channel μ L (0.3) = 0.5μ M (4) = 0.33 μ M (0.3) = 0.5μ B (4) = 0.67
    These values are again set by the fuzzy reference engine, μ NS (reserved channel tuning) ≒ 0.33, μ NM (reserved channel tuning) = 0.5, μ zero approximation (reserved channel tuning) ≒ 0.33, μ NS (reserved channel tuning) It has four fuzzy output vectors equal to 0.5.
    In other words, the membership function for the first reserved channel tuning is that the first row 2 row and the second row 2 row of Table 1 have 8 rows of the fuzzy rule base of FIG. If the channel is medium (M), the final reserved channel is tuned to negative small (NS)), and its membership level is 0.33 by the minimum approximation. The second result is the result of column 1, row 2 and column 2, row 3 of Table 1. In the same way, the third and fourth results are column 1, column 3, column 2, column 1, column 3, and column 3. The result for the row. Finally, the fuzzy logic controller 50 outputs the creep value -1.67 for clear control of the four fuzzy output vectors obtained as described above by the centroid method, and this value is a value for tuning the last reserved number of reserved channels. Becomes Since the number of reserved channels to be set is an integer, if the tuning value is added to the number of reserved channels last set in the above assumption, "4", the result is "2". Finally, the output of the fuzzy logic controller 50 is "2". "Becomes.
    After the new reserved channel is set (43) by the output of the fuzzy logic controller 50, it is determined whether the handoff call is available in the normal channel (44), and the channel is allocated if it is available (46). If the reserved channel is available (45), the channel is allocated using the reserved channel (46). If the reserved channel is not available, the call is forced to connect to the terminal (47).
    According to the present invention as described above, by using a fuzzy logic controller to adaptively set the reservation channel of the appropriate size to cope with the flow of handoff traffic, it is possible to efficiently cope with the changing handoff traffic density, As a result, waste of channel resources is reduced, and system performance and reliability are greatly increased.
    权利要求:
    Claims (1)
    [1" claim-type="Currently amended] Sampling the size (quantity) of the handoff calls to a fuzzy logic controller at a predetermined time interval together with the number of preset reserved channels, and a predetermined time depending on the size (quantity) of the handoff calls in the fuzzy logic controller. To output the control volume at intervals, and to adjust the reserved channel for the traffic volume of the handoff call to be sampled after a certain time by setting the reserved channels adjusted by the control volume in the current reserved channel in the base station signal processor And a step of feedback to the fuzzy logic controller to selectively adjust the reserved channel according to the traffic density of the handoff call.
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    同族专利:
    公开号 | 公开日
    US6144856A|2000-11-07|
    CN1106775C|2003-04-23|
    CN1219083A|1999-06-09|
    KR100258222B1|2000-06-01|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    1997-11-29|Application filed by 서평원, 엘지정보통신 주식회사
    1997-11-29|Priority to KR1019970064790A
    1999-06-15|Publication of KR19990043748A
    2000-06-01|Application granted
    2000-06-01|Publication of KR100258222B1
    优先权:
    申请号 | 申请日 | 专利标题
    KR1019970064790A|KR100258222B1|1997-11-29|1997-11-29|A handoff guard channel setting method of base station|
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