KR20020034540A - Method for canceling 1pps glitch in mobile bsc system - Google Patents

Abstract

PURPOSE: A method for removing 1PPS(Pulse Per Second) glitch in a BSC(Base Station Controller) is provided to stabilize the hand-off process between BTS(Base Transceiver Stations) and call quality by being synchronized to 1PPS of a GPS(Global Positioning System) and embodying the stability of 50Hz used in the hand-off between the BTSs. CONSTITUTION: If a current time is 1PPS receiving period(S1), a clock distributor receives 1PPS clock from a GPS receiver(S2). The clock distributor calculates a GPS reset value for detecting a glitch using the 1PPS clock and 50Hz clock generated in a previous period(S3). The clock distributor judges whether the GPS reset value is 1 within a setting time from a falling edge of the 1PPS clock(S4). If the GPS reset value is 1 within the setting time from the falling edge of the 1PPS clock, the clock distributor judges whether the GPS reset value is 1 within a next setting time from the setting time(S5). If the GPS reset value is 1 within the next setting time from the setting time, the distributor GPS reset value is 1 within a next setting time from the setting time(S6). If the GPS reset value is 1 within the next setting time from the setting time, the clock distributor cleans the 1PPS clock and initializes the GPS reset value as 0(S7).

Description

METHODS FOR CANCELING 1PPS GLITCH IN MOBILE BSC SYSTEM}

The present invention relates to a method of removing 1 glitches (GPS) in a mobile communication control station system, and more specifically, a GPS (Global Positioning System). The present invention relates to a method of eliminating 1PPS gritty in a mobile communication control station system that stabilizes inter-base station handoff processing and call quality by eliminating noise, ie, odor, of a signal generated at a 1PPS output.

A Clock Distributor (CKD) installed in a conventional mobile communication control station system receives a 1PPS clock from a GPS receiver at regular intervals, and then uses a 1PPS clock to perform 50Hz (20ms) hand-off processing between base stations. Generate the clock.

However, since the clock divider in the conventional mobile communication control system does not have an algorithm to remove the signal noise included in the 1PPS clock, that is, the glitches, 50Hz (20ms) using the unstable 1PPS clock including the griches is included. Generated the clock.

At this time, since the 50Hz clock synchronized to the 1PPS clock is used for handoff between base stations, if this time is misaligned, a problem occurs in handoff between pedestrians and base stations or between base stations.

Therefore, when the signal noise occurs in 1PPS as described above, 50Hz (20ms) used in the vocoder board is shaken, which greatly affects the handoff processing between the base stations and the call quality. There was a problem that the mobile communication system is unstable.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to achieve stabilization of 50 Hz used for inter-base station handoff in synchronization with 1PPS of GPS, thereby performing inter-base station handoff process and The present invention provides a method for eliminating 1PS gripe in a mobile communication control station system for stabilizing call sound quality.

In order to achieve the above object, the method of eliminating 1PS gripping in the mobile communication control station system of the present invention includes a GPS receiver receiving 10MHz and 1PPS clock from a GPS satellite, and a rising edge of the 1PPS clock output from the GPS receiver. In the method of eliminating 1PS grosches in a mobile communication control station system having a clock divider that generates a 50 Hz clock and generates the vocoder board accordingly,

A first step of determining, by the clock distributor, whether the current time point is a 1PPS reception period;

A second step of, if the current time point is not a 1PPS reception period in the first step, proceeds to the first step again, and if the current time point is a 1PPS reception period, the clock divider receives a 1PPS clock from the GPS receiver;

A third step of calculating a gripping detection GPS reset (GPSRET) value using the clock divider generated by the clock divider and the 50 Hz clock generated during the previous period;

A fourth step of determining, by the clock divider, whether a GPS reset (GPSRET) value within a set time (t) from a falling edge of the 1PPS clock is "1";

In the fourth step, if the GPS reset (GPSRET) value within the set time (t) from the falling edge of the 1PPS clock is "1", the clock divider sets the GPS reset within the next set time (t) from the set time (t). A fifth step of determining whether or not the GPSRET) value is "1";

If the GPS reset (GPSRET) value within the set time (t) from the set time (t) to the next set time (t) is "1" in the fifth step, the clock divider sets the GPS within the set time (3t) from the set time (2t). A sixth step of determining whether the reset value (GPSRET) is "1"; And

In the sixth step, if the GPS reset (GPSRET) value from the set time (2t) to the next set time (3t) is "1", the clock divider resets the 1PPS clock and at the same time, the GPS reset for gritty detection ( And a seventh step of initializing and returning the GPSRET) value to "0".

1 is a functional block diagram showing a configuration of a 1PS grip removal apparatus in a mobile communication control station system according to an embodiment of the present invention;

2 is an operation flowchart showing a method for removing 1PS grit in a mobile communication control station system according to an embodiment of the present invention;

FIG. 3 is an operation flowchart showing the detailed operation of the third step S3 in the method of removing 1PS grit in the mobile communication control station system according to FIG. 2;

FIG. 4 is a signal timing diagram for explaining a method of eliminating 1PS grip in the mobile communication control station system according to FIG. 2.

<Explanation of symbols for the main parts of the drawings>

100: GPS receiver 200: clock divider

300: Vocoder Board

Hereinafter, a method of eliminating 1PS grit in a mobile communication control station system according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a functional block diagram of a 1PS degreaser removal device in a mobile communication control station system according to an embodiment of the present invention, the 1PPS deodorant device in a mobile communication control station system according to an embodiment of the present invention GPS receiver 100, and clock divider 200.

The GPS receiver 100 receives the 10 MHz and 1 PPS clocks at predetermined intervals from the GPS satellite 1 and outputs the clock to the clock divider 200.

In addition, the clock divider 200 receives a 1PPS clock from the GPS receiver 100 at every 1PPS reception period and generates a 50Hz clock according to the rising edge of the 1PPS clock, and then the vocoder board 300. It acts as a generator.

In this case, since the 1PS GPS griches removal algorithm is loaded in the clock divider 200, when the 1PPS clock output from the GPS receiver 100 includes griches as shown in FIG. 3, the 1PPS clock is removed. After extinguishes and serves to receive a 1PPS clock of the next period from the GPS receiver 100.

Then, FIG. 2 and FIG. 3 show a method for removing 1PS gross odor in a mobile communication control station system according to an embodiment of the present invention using the 1PS grit removing device in the mobile communication control station system having the above configuration. This will be described with reference.

FIG. 2 is an operation flowchart showing a method for removing 1PS grip in a mobile communication control station system according to an embodiment of the present invention.

First, the clock divider 200 determines whether the current time point is a 1PPS reception period (S1).

At this time, if the current time point is not the 1PPS reception period in the first step S1 (NO), the clock divider 200 proceeds to the first step S1 again, and if the current time point is the 1PPS reception period (YES). The clock divider 200 receives a 1PPS clock from the GPS receiver 100 (S2).

Thereafter, the clock divider 200 calculates the GPS detection (GSRSRET) value for the gritty detection using the 1PPS clock and the 50Hz clock generated in the previous period (S3).

Hereinafter, a detailed operation process of the third step S3 will be described with reference to FIGS. 3 and 4.

First, as illustrated in FIG. 4, the clock divider 200 delays the 1PPS clock received from the GPS receiver 100 by 244 ns to generate a “1PPS Delay” clock (S3-1).

Then, the clock divider 200 generates an "ADDPPS" clock between the rising time of the 1PPS clock and the rising time of the "1PPS Delay" clock as shown in FIG. 4 (S3-2). If the "ADDPPS" clock is generated using the 1PPS clock including the griches, as shown in FIG. 4, another "ADDPPS" clock is generated due to the gritty of the 1PPS clock.

Subsequently, as shown in FIG. 4, the clock divider 200 synchronizes the polling time of the 1 PPS clock and the rising time of the 50 Hz clock generated at the previous period (S3-3).

Then, the clock divider 200 calculates a GPS reset (GPSRET) value by logically multiplying the high-level portion of 50 Hz and the "ADDPPS" clock generated in the previous cycle as shown in Equation 1 below (S3-). 4).

ADDPPS * 50 Hz = GPSRET

Subsequently, the clock divider 200 determines whether the GPS reset (GPSRET) value within the set time (t = 244ns) is "1" from the falling edge of the 1PPS clock (S4). At this time, if the GPS reset (GPSRET) value within the set time (t = 244ns) from the falling edge of the 1PPS clock in the fourth step (S4) described above is "1", the 1PPS clock contains a gritty, and the 1PPS If the GPS reset (GPSRET) value within the set time (t = 244 ns) from the falling edge of the clock is “0”, it means that the grip is not included in the 1PPS clock.

At this time, if the GPS reset value (GPSRET) within the set time (t = 244ns) from the falling edge of the 1PPS clock in the fourth step (S4) is "1" (YES), the clock divider 200 sets the set time (t). = 244 ns), it is determined whether or not the GPS reset (GPSRET) value within the next set time (2t = 488 ns) is "1" (S5).

If the GPS reset (GPSRET) value in the fifth step (S5) from the set time (t = 244ns) to the next set time (2t = 488ns) is "1" (YES), the clock divider 200 sets the set time. From (2t = 488ns), it is determined whether or not the GPS reset (GPSRET) value within the next set time (3t = 976ns) is "1" (S6).

At this time, if the GPS reset value (GPSRET) in the sixth step (S6) from the set time (2t = 488ns) to the next set time (3t = 976ns) is "1" (YES), the clock divider 200 At the same time, the 1PPS clock is extinguished, and the GPS detection for GPS detection (GPSRET) is initialized to " 0 " (S7). Therefore, the clock divider 200 supplies the 50 Hz clock generated in the previous cycle to the vocoder board 300.

On the other hand, if the GPS reset (GPSRET) value within the set time (t = 244ns) from the falling edge of the 1PPS clock in the fourth step (S4) is "0" (NO), the clock divider 200 determines the 1PPS clock. A 50Hz clock is generated according to the rising edge of the signal and supplied to the vocoder board 300, and then the process proceeds to the first step S1 (S8).

Meanwhile, in the fifth step S5, the GPS reset GPSRET value from the set time t = 244ns to the next set time 2t = 488ns is “0” (NO), or the sixth step S6. If the GPS reset (GPSRET) value from the set time (2t = 488ns) to the next set time (3t = 976ns) is "0" (NO), the clock divider 200 resets the 1PPS clock before the previous period. When the 50Hz clock generated at the time is supplied to the vocoder board 300, the process proceeds to the first step S1 (S9).

As described above, according to the method of eliminating the 1PS grip in the mobile communication control station system according to the present invention, by allowing the clock divider to supply a more stable 50Hz clock to the vocoder board, the inter-base station handoff process and It has an excellent effect of stabilizing call quality.

Claims (6)

In a mobile communication control system having a GPS receiver receiving 10 MHz and 1 PPS clock from a GPS satellite and a clock divider generating a 50 Hz clock according to the rising edge of the 1 PPS clock output from the GPS receiver and generating it to a vocoder board. In 1PS grit removal method, A first step of determining, by the clock distributor, whether the current time point is a 1PPS reception period; A second step of, if the current time point is not a 1PPS reception period in the first step, proceeds to the first step again, and if the current time point is a 1PPS reception period, the clock divider receives a 1PPS clock from the GPS receiver; A third step of calculating a gripping detection GPS reset (GPSRET) value using the clock divider generated by the clock divider and the 50 Hz clock generated during the previous period; A fourth step of determining, by the clock divider, whether a GPS reset (GPSRET) value within a set time (t) from a falling edge of the 1PPS clock is "1"; In the fourth step, if the GPS reset (GPSRET) value within the set time (t) from the falling edge of the 1PPS clock is "1", the clock divider sets the GPS reset within the next set time (t) from the set time (t). A fifth step of determining whether or not the GPSRET) value is "1"; If the GPS reset (GPSRET) value within the set time (t) from the set time (t) to the next set time (t) is "1" in the fifth step, the clock divider sets the GPS within the set time (3t) from the set time (2t). A sixth step of determining whether the reset value (GPSRET) is "1"; And In the sixth step, if the GPS reset (GPSRET) value from the set time (2t) to the next set time (3t) is "1", the clock divider resets the 1PPS clock and at the same time, the GPS reset for gritty detection ( And a seventh step of initializing and returning the GPSRET) value to " 0 ". The method of claim 1, If the GPS reset (GPSRET) value within the set time (t) from the falling edge of the 1PPS clock in step 4 is "0", the vocoder board simultaneously generates the 50Hz clock according to the rising edge of the 1PPS clock. And a eighth step of proceeding to the first step after supplying to the first PSG odor in the mobile communication control station system. The method of claim 1, The GPS reset (GPSRET) value in the fifth step from the set time t to the next set time 2t is "0", or in the sixth step from the set time 2t to the next set time 3t. If the value of the GPS reset (GPSRET) is "0", after the clock divider resets its 1PPS clock, supply the vocoder board with the 50Hz clock generated in the previous cycle, and then proceed to the first step. A method of eliminating 1PS grit in a mobile communication control station system, the method comprising: a; The method of claim 1, And the interval from the falling edge of the 1PPS clock to the set time (t) in the fourth step is 244 ns. The method of claim 1, The third step may include: a third step of the clock divider generating a “1PPS Delay” clock by delaying a 1PPS clock by a predetermined time; Step 3-2, wherein the clock divider generates an "ADDPPS" clock between the rising time of the 1PPS clock and the rising time of the "1PPS Delay" clock; Step 3-3, wherein the clock divider synchronizes the timing of polling the 1PPS clock and the rising time of the 50 Hz clock generated during the previous period; And And a third to fourth step of calculating a GPS reset (GPSRET) value by logically multiplying the high level portion of the 50 Hz generated by the clock divider and the "ADDPPS" clock. How to remove 1PS grit. The method of claim 5, And the " 1PPS Delay " clock in the step 3-1 delays the 1PPS clock by 244 ns.