KR950003470B1 - Channel catching method considering channel busy probability - Google Patents

Abstract

(1) sequentially changing the channel number in the non-call state and respectively examining the use of the corresponding channel; (2) displaying the use frequency number of each corresponding channel according to the use number in response to the fact the corresponding channel is in use; (3) comparing the using frequency of a predetermed channel to that of the current priority channel in response to the corresponding channel is not in use, determining the channel having lower using frequency as a new priority channel, and thereby respectively determining the order of another channels; and (4) a forming the speech channel on basis of the channel according to the channel priority determined in the channel priority determining step in response to the signal detection corresponding to the speech path forming request during the channel examining step.

Description

Channel capture method considering channel busy probability

1 is a block diagram of a wireless telephone.

2 is a conventional channel acquisition flowchart.

3 is a channel acquisition flowchart according to the present invention.

* Explanation of symbols for main parts of the drawings

10: central processing unit 11: ROM

12: Romans 13: RF section

The present invention relates to a channel acquisition method of a wireless communication device, and more particularly to a method for capturing a channel in consideration of the busy probability of the channel.

The wireless communication device forms an RF link between two devices using a channel, and then performs wireless communication through the formed RF link.

1 is a configuration diagram of a radiotelephone, in which the RF components of the base unit and the handset unit are configured in the same manner.

In the configuration of FIG. 1, it can be seen that the audio processing unit of the fixing device and the portable device is omitted, and the configuration of the wired interface of the fixing device is also omitted. Referring to the above configuration, the RF unit 13 has a known configuration including a transmitter 14, a receiver 15, and a frequency synthesizer 16 of an RF signal, and receives received channel data (CD). As a result, the transmission channel or the reception channel is locked to form an RF link. Patent No. 90-2140 filed by the present applicant discloses in detail the respective components in the RF unit 13 and the operation thereof. The ROM 11 is an EEPROM and stores an ID code (Indenfication code) which is a unique number of the wireless communication device. The CPU 10 transmits a channel data CD, a data strobe signal (DS) and a clock (CK) to the frequency synthesizer 16 of the RF unit 13 as necessary. Lock the channel for RF link formation of (13), output the transmission data TXD to the modulator 17, and receive the response data RXD from the counterpart through the receiver 15 and the demodulator 18 for RF link formation. When the response data RXD is identical to its ID code, the ID code of the ROM 11 is read to form an RF link to perform call processing.

A conventional process of capturing a channel in such a wireless telephone will be described with reference to FIG.

First, when power is first supplied to a fixed device or a portable device, a start channel is determined according to a predetermined rule. The central processing unit 10 controls the bus line so that the ID code of each device from the ROM 11 can be determined. (ID code) is read and stored in the internal RAM 19. Then, the start channel is calculated using this ID code. The calculation method is to add the numbers from 6 to 8 digits to 5 digits from the last bit of the ID code, and then increase by 1.

Starting channel number formula

… … … … … … … X8 X7 X6 X5 X4 X3 X2 X1 → ID CODE

Start channel number = X5 X4 X3 X2 X1 + X8 X7 X5 + 1

For example, assuming that the ID code of an arbitrary device is "ECAO _H ", since the last 8 bits "AO _H " of the ID code is "1010 0000 _B ", it can be seen that the start channel number is calculated as follows.

"Start channel number = 00000 + 101 + 1 = 110"

Therefore, the start channel number becomes the sixth channel, and during the call, the access channel always starts to form the RF link.

Hereinafter, a conventional channel capturing method will be described in more detail with reference to FIGS. 1 and 2. When power is supplied to the fixed device or the portable device, the central processing unit 10 first assigns a pre-stored start channel number as a channel number in step 201 and performs a subsequent process. That is, the start channel number calculated according to the ID code stored in the ROM 11 is set to the channel number CHNO and stored in the internal RAM 19. In step 202, the RF unit uses the DS, CK, and CD lines. Fix the channel of (13). After comparing the reference signal strength with the received signal strength input to the 20 dB line of the demodulator 18 in step 203, the RAM 19 value of the channel number CHNO in step 209 if the channel is idle. Increase by 1. In step 210, if the channel value is the last channel (channel 40 becomes the last channel in the case of a 40CH radiotelephone), the channel value is converted to the first channel number CH1, otherwise the process returns to step 202 immediately above. Goes. However, if it is determined in step 203 that the call is busy, the data of the corresponding channel is received in step 204. In step 205, the received ID code is compared with the ID code stored in the ROM 11. The above process is repeated from step 209, and if there is a match, the answer data is sent in step 206 to enter the call state. If a call termination state occurs in a call state, the process is performed again from step 201.

Therefore, if the channel is captured in the same manner as in FIG. 2, 40 channels are sequentially scanned from the start channel number for each call, and data is received / answered in the free channel to make a call. . However, in the conventional channel acquisition method as described above, since its ID code is determined, the starting channel number is always fixed. However, with the increase in wireless communication devices, many devices are operating within the same coverage area. In this case, if the same ID codes are used with other subscribers with frequent use of the radio call, the frequency of use of the starting channel number becomes high, and the channel is likely to be busy. In addition, since the channel acquisition process is always performed sequentially from the starting channel number, the process of finding a free channel becomes long, resulting in a long call formation time.

Accordingly, an object of the present invention is to check the frequency of use of each channel during a non-call in a wireless communication device, and to quickly form a call by attempting to form an RF link from a channel number having a low use frequency when forming an RF link. In providing.

Another object of the present invention by sequentially scanning the presence or absence of all the channels in the idle state to measure the frequency of use of each channel and by setting the priority from the channel with a low frequency of use according to the frequency of use, the busy probability of all channels In this paper, we provide a way to store the usage priority table for each channel to capture channels.

Still another object of the present invention is to provide a method for quickly capturing an empty channel by attempting to form an RF link according to a channel number registered in a priority table when an RF link is required in a wireless communication device.

Hereinafter, the present invention will be described in detail with reference to the drawings.

The configuration of the wireless communication device for carrying out the present invention is the same as in FIG. 1, and the reference numerals are the same. However, the central processing unit 10 of FIG. 1 performs the control operation as shown in FIG. 3 according to the object of the present invention.

3 is a flow diagram of channel acquisition according to the present invention. First, in step 301, the central processing unit 10 sets a channel number (PRCH) having the highest priority. Thereafter, in step 302, the presence or absence of a ring detection is checked, and if a ring is detected, the flow proceeds to step 314, and if not, the flow proceeds to step 303. In step 303, it is checked whether the locked channel is in a busy state. If it is in a busy state, the process proceeds to step 305; otherwise, it proceeds to step 309. In step 305, if the received frame data is magnetic data, the process proceeds to step 307, and if it is magnetic data, call processing is performed. Otherwise, step 308 is performed. In step 308, the busy counter of the corresponding channel number is incremented and the process proceeds to step 302. In step 309, the priority channel PRCH is set, the variable X is initialized, and step 310 is performed. In step 310, it is checked whether the variable X is greater than the maximum channel number (MXCH). In step 311, the variable X is increased by 1 and the flow proceeds to step 312. In step 312, it is checked whether the busy counter of the priority channel PRCH is larger than the busy counter of the X variable channel. If the busy counter is larger, the process proceeds to step 313 and, if otherwise, to step 318. In step 313, the channel number of the X variable is first set to the channel number PRCH, and the flow proceeds to step 318. In step 318, the priority of the channel number according to the busy counter is sorted according to the priority change, and the flow proceeds to step 310. In step 314, the channel number PRCH is locked first, and then step 315 is performed. In step 315, it is checked whether the corresponding locking channel is busy. If the busy channel is busy, step 316 is performed. Otherwise, step 307 is performed. In step 316, it is checked whether there is a channel having the next priority, and if so, the process proceeds to step 317; otherwise, the process proceeds to step 314. In the step 317, after locking to the channel having the next priority, the process proceeds to the step 315.

Therefore, referring to the flowchart of FIG. 3, first, channel numbers are sequentially fixed, and then the fixed channel is checked for busy status. If the corresponding channel is busy in the checking process, the busy counter of the corresponding channel is increased and the process proceeds to the checking process. If the corresponding channel is in the free state, the channel variable is initialized and the busy channel value PRCH having the minimum busy counter value is compared with the busy counter value of the current channel number. At this time, if the busy counter value of the current channel number is small, the corresponding channel number is first set to the channel number PRCH. In the checking process, the priorities of the channels are sorted by busy counter values of the remaining channels after changing the channel number PRCH. Thereafter, after increasing the channel variable, it is checked whether the maximum channel number is obtained or repeats the above process and returns to the channel checking process if the maximum channel number is obtained. When detecting a ring in the channel inspection process, the channel is fixed to the channel according to the priority to form a communication path.

Based on the above configuration, the operation of the present invention will be described in detail with reference to FIGS. 1 and 3.

First, when power is first supplied to a fixed device or a portable device, a start channel is determined according to a predetermined rule. The central processing unit 10 controls a bus line to read an ID code of each device from the ROM 11 to internally. After storing in the RAM 19, this ID code is used to calculate the start channel. The calculation method is to add up to 5 digits (X5 X4 X3 X2 X1) from the end of the ID CODE, followed by 6 to 8 digits (X8 X7 X5), Just add In summary, the starting channel number is as follows.

… … … … … … … X8 X7 X6 X5 X4 X3 X2 X1 → ID CODE

Start channel number = X5 X4 X3 X2 X1 + X8 X7 X5 + 1

The CPU 10 stores the value calculated from the above calculation formula in the RAM 19 therein, and sets the start channel number stored in the RAM 19 as the channel number PRCH in step 301. After the initialization process, the channel is scanned. The start channel number as described above is set to the dominant channel number PRCH only in the initial initialization process, and then the channel number PRCH is first determined in the following manner.

Subsequently, determining the channel number PRCH is performed in the idle state. The CPU 10 checks whether a ring signal is detected in step 302, and proceeds to step 303 when the ring is not detected, i.e., in an idle state.

In step 303, the central processing unit 10 outputs the data strobe signal DS, the clock CK, and the channel number data CD through the DS, CK, and CD lines to the frequency synthesizer 16 to receive the receiver of the RF unit 13 ( 15) is locked to the next channel number, and in step 304, the received signal strength is checked through the 20 dB line to determine whether the received signal strength of the corresponding channel is greater than the reference signal strength. That is, when the received signal strength is greater than the reference signal strength, the channel number is used by another wireless telephone, and when the received signal strength is smaller than the reference signal strength, the corresponding channel is free. Therefore, if the strength of the received signal is greater than the reference signal strength, since the corresponding channel is busy, the signal is received in step 305 for a predetermined time (corresponding to one frame of data), and then the signal received in step 306. Is compared with the ID code of the ROM 11 to check if the data has the same identification number. If data having the same serial number is received, it is magnetic data, so the general call processing is performed in step 307. Here, the magnetic data is mapped to the ROM 11 as an ID code promised between the fixed device and the portable device to form a call of the radiotelephone.

However, if the same serial number and the same data is not received in step 306, this means that the other channel is using the corresponding channel, so that the busy counter of the current channel number locked in step 308 is used. Increase by 1 and go back to perform step 302 again. The busy counter is a counter that stores the number of times of busy state detected in a corresponding channel and generates reference data for determining the priority of each channel. The busy counter is an 8-bit counter that simultaneously divides all busy counter values by a predetermined number at regular time intervals to prevent overflow of the bit counter.

On the other hand, in step 304, if the intensity of the received signal is less than the reference signal, the corresponding channel is in the free state, and at this time, the CPU 10 performs steps 309 to 318. The central processing unit 10 initializes the channel number PRCH and the channel variable X for adjusting the priority to 0 in step 309. In step 310, it is checked whether the channel variable X is greater than or equal to the largest channel number MXCH that has already been determined. If the channel variable X is greater than or equal to the largest channel number MXCH, it will be generated after performing steps 311 to 318, which will be described later. In this case, the central processing unit 10 returns to step 302 described above.

However, in the initialized state as in step 309, step 311 is performed because the channel variable X is smaller than the largest channel number MXCH in step 310. In step 311, the channel variable busy counter is increased by one. In operation 312, the busy counter value of the current priority channel number PRCH is compared with the busy counter value of the channel variable X. If the value of the current priority channel number PRCH is greater than or equal to the busy counter value of the channel, the CPU 10 sets the channel number of the current channel variable X to the new priority channel number PRCH in step 313. The process then proceeds to step 318. However, if the current priority channel PRCH is not greater than the busy counter value of the channel variable X in step 312, the flow proceeds directly to step 318. In step (312) and step (313), a channel number having a low frequency of use becomes a priority channel PRCH. In step (318), the determined priority channel and the ranks of subsequent channels are determined based on the busy counter value. To sort. After performing step 318, the CPU 10 returns to step 310, and repeats steps 310 to 318 when the channel variable X becomes the maximum channel number. If the channel variable X becomes the maximum channel number in step 310, the channel priority change (or setting) of all channels is recognized as complete and the process returns to step 302.

The central processing unit 10 checks whether a ring signal introduced through the receiver 15 and the demodulator 18 has been detected in step 302, and if detected, steps 309 through 318 in step 314. The channel data CD corresponding to the highest-priority channel number PRCH calculated in step (a clock CK and data strobe signal DS are also output) to the scan-synthesizing unit 16 of the RF unit 13, and the frequency synthesis unit ( 16) locks the channel of the receiver 15 to the value of the channel data CD corresponding to the highest priority channel. Accordingly, the received signal strength is applied to the CPU 10 through the 20 dB measurement line of the receiver 15.

The CPU 10 checks the use of the corresponding channel number by comparing the received signal strength received through the 20 dB measurement line through the locked channel in step 315 with a predetermined reference signal strength. As a result of the measurement, if the received signal strength is smaller than the reference signal strength, the corresponding channel number and the free state are performed. Therefore, the process proceeds to step 307 to perform a call in a predetermined order. However, if the strength of the received signal is greater than the reference signal, the corresponding channel number is being used. In step 316, it is checked whether there is a channel in the next order. The steps from step 315 are repeated. However, in step 316, if there is no next priority channel, that is, by searching for the lowest priority channel, the control returns to step 314 to repeat the locking control of the highest priority channel. Therefore, it can be seen that a call is attempted by locking the channel according to the priority channel number PRCH rank setting so that a channel with low use frequency is preferentially locked during ring detection.

As described above, the call formation time varies greatly depending on the scanning method of the channel, especially in a place where the frequency of use of the wireless phone is high. The advantage is that you can change the start channel yourself so that you can capture the channel in the shortest time possible.

Claims (3)

In the channel acquisition method of the wireless communication device, the channel number is sequentially changed in the non-call state, and the channel inspection process checks whether each channel is used or not, and responds that the channel is in use during the channel inspection process. A channel frequency display step of displaying a frequency of use of each corresponding channel according to the number of times of use, and a frequency of use of any channel in response to the non-use state of the channel in the channel checking process. A channel prioritization process of determining a channel having a lower frequency of use as a new priority channel and comparing the remaining frequency with the frequency of use, and determining the priority of the remaining channels based on the order of low frequency of use. Determining the channel priority in response to signal detection corresponding to a call path formation request during Channel acquisition method considering the channel busy probability, characterized in that the process of attempting to make a call based on the channel according to the channel priority determined in the process. A channel acquisition method of a wireless device, the method comprising: a first step of checking whether a ring is received; a second step of locking a channel number and checking a state of a corresponding channel when the ring is not ringing in the first step; In the second process, the busy counter of the corresponding channel is increased to return to the first process and the free state temporary priority channel number is set in the second process, and the busy counter value of the other channels and the preferred channel are set. Comparing a busy counter value of the number to set a channel having the smallest counter counter value as a priority channel, and a fifth process of locking a priority channel number when a ring is called in the first process to attempt a call; Channel acquisition method considering the channel busy probability characterized in that. 3. The method of claim 2, wherein the priority channel setting process comprises: a first step of setting a priority channel number and initializing a channel variable; and a busy counter value of the priority channel and a busy counter value of the current variable channel after performing the first step. Comparing a second counter with a second counter in the second step and checking whether the busy counter value of the first channel is greater than the busy counter value of the current variable channel; The third step of maintaining the first channel as it is, the fourth step of adjusting the priority of each channel according to the busy counter value of the current variable channel after performing the third step, and increasing the channel variable after performing the fourth step After checking whether the current channel variable exceeds the maximum channel number, if it is exceeded, the first channel setting process is terminated, and if not, the fifth step returns to the second step. Considering the busy channel probability that the burden feature captures channel.