KR950004754B1 - Automatic transmitting switching device for mobile telecommunications - Google Patents

Abstract

The device comprises a detector(10) for detecting voice output from a micro amp(11), a comparator(U2) for comparing a set bias voltage(VSB) with an output level of detector(10), a sensing part(20), a receiver(12), a transmitter(30), and a micom(40) for controlling transmitter(30) and comprising a SAT fade lock timer(TA), a timer(TB) for setting maximum transmitting stop time. The sensing part(20) comprises an A/D converter(21) for sending RSSI(received signal strength indicator) level of the receiver(12) to the micom(40), SAT PLL (phase locked loop,22) and a data PLL(23).

Description

Automatic transmission switch device for mobile communication

1 is a circuit diagram showing an automatic transmission switch device for a mobile communication of the present invention.

2 is a flow chart showing the operation of the present invention.

3 is a timing diagram of the present invention.

* Explanation of symbols for main parts of the drawings

10: detector 11: microphone amplifier

12: receiver 20: detector

21: A / D converter 22: SAT phase synchronization loop

23: data phase synchronization loop 30: transmitter

40: mi-com U2: comparator

VB: Bias Voltage TA: SAT Fade Lock Timer

TB: Timer for setting maximum transmission stop time

TC: Timer to prevent intermittent syllables

According to the present invention, even when there is no support for the Vox (Voice Operated Transmission) function in the mobile communication system, the terminal performs the VOX function by itself and saves power consumption. The present invention relates to an automatic transmission switch device for mobile communication.

In general, VOX (Voice Operated Transmission) means that when there is no caller's voice during a call, that is, when the terminal user only listens to the other party and does not speak, the caller cuts off the channel. Refers to the automatic transmission switching device by voice that connects immediately.

Therefore, it is obvious that power consumption is saved by the transmission stop time even when there is no voice.

To this end, the existing mobile communication system (Cellular System) informs the terminal using one bit of the Overhead Message transmitted from the base station at all times whether the VOX function is authorized or not, and the terminal type identification display ( Station Class Mark (SCM) indicates whether the base station uses VOC.

When using the VOX mode function, if the other party is not using the transmission circuit while receiving only, it cuts off the transmission circuit and reduces the battery consumption.In this case, the audible supervisory tone (SAT) is detected for some time. If you do not know that the base station and the terminal is already operating in mutual VOX function mode, the call is not blocked.

Meanwhile, the reason why the terminal should continuously transmit to the base station during a call is as follows. In other words, the Cellular System must share the channel in terms of providing services to multiple users by using a limited channel (RF Channel). If the user interrupts the call, the system immediately detects the service. Must provide a call path to the next user who needs it, and should be able to manage it separately even if another subscriber station uses the same channel.

For this purpose, the Super-visory Audio Tone (hereinafter referred to as the SAT) function is used. There are three types of audible supervisory tones such as 5970, 6000, and 6030 Hz (Amps Sysrem (American Standard)). Transmit one of the frequencies by mixing with the voice signal to determine the presence or absence of the other party (whether or not the channel is in use) on the other side of the call, and to determine the status of the call by determining the continuous connection to the call or blocking the call. Perform control.

It also introduces the concept of a fade timer (5 seconds) in case the terminal leaves the service area during a call or passes through a blind spot where the call is poorly connected.斷續) If there is, it does not block the channel immediately but it can be connected again to continue the call.

In this case, however, there is an advantage that the call can be continued by setting the call dead zone call time according to the fade timer (5 seconds), but in some cases, if the time of 5 seconds is repeated repeatedly, there is a disadvantage that a considerable battery consumption occurs.

Therefore, in order to solve the above-mentioned problems, the present invention provides a system in which the VOX function is not supported. If the current terminal is located in a strong electric field, if there is no dial tone by using the function of the fade timer, the present invention is about 3 It is characterized by reducing the power consumption by blocking the transmission line for a second, to this end, the present invention is not in the VOX mode state even if the VOX function is not allowed in the system) within the range that the terminal itself does not destroy the system of appointments. Independently executes the VOX function to reduce power consumption.

That is, the present invention provides a detection unit for detecting an audio output from a microphone amplifier; A comparator for comparing the output level of the detector with the set bias voltage; A detector for detecting a receiver state; The transmitter is controlled by checking the state of the comparator and the detector, and a device composed of a microcomputer including a fade timer divided into a SAT fade lock timer and a timer for setting a maximum transmission stop time is installed in the terminal, and the call is transferred from the terminal itself. It is to be blocked.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a circuit diagram showing a transmission automatic switch device installed in a terminal (mobile phone) according to the present invention, comprising: a detector 10 for detecting audio output from the microphone amplifier 11; A comparator (U2) for comparing the output level of the detector (10) with a set bias voltage (VB); A receiving unit 12; A transmitter 30; A detector 20 for detecting a state of the receiver 12; The transmitter 30 operates according to the output of the detector 20 and the comparator U2, and includes a SAT fade lock timer TA and a timer TB for setting the maximum transmission stop time. ); The detector 10 includes a capacitor C1 coupling the microphone-amp 11 signal, resistors R1-R4 for providing a predetermined level to the op-amp U1 through the capacitor C1, Comprising a diode (D1, D2) rectifying in both directions at the input / output terminal of the op-amp (U1); The sensing unit 20 includes an A / D converter 21 for providing a received signal strength indicator (RSSI) of the receiving unit 12 to the microcomputer 40; A SAT phase-locked loop 22 for turning on / off a voice (audio) signal and providing it to the microcomputer 40; And a data phase locked loop 23 that controls the data and provides it to the microcomputer 40.

In addition, the value input to the non-inverting terminal of the comparator U2 is the output value of the detector 10 input through the resistor R5 and the capacitor C2, and the value input to the inverting terminal is the resistor R6 and R7. A bias voltage VB divided and inputted by; The micro-com 40 includes a central processing unit (CPU) and peripheral logic, and also controls a timer TC for preventing inter-syllable syllables.

Hereinafter, an operation process of the present invention configured as shown in FIG. 1 will be described with reference to the flowchart of FIG. 2 and the timing diagram of FIG. 3.

First, when a user attempts to make a call, a control channel (not shown) is assigned a Voice Channel (an RF channel where the actual call is made) from the system, and each of the predetermined SAT Color Codes (SCC) After the confirmation, it starts to operate on the micro-com 40 and checks whether the call mode is present (T2), then checks whether there is a message to be answered to the base station (T3), and if there is no message to respond, the SAT fade lock The timer TA is reset (T4).

Of course, if not in the call mode (T2), the initial state is maintained and transmission is stopped (T13). At this time, the strength of the received signal strength indicator (RSSI) indicating the level of the received signal of the current state detected by the receiver 12 is converted into a digital signal through the A / D converter 21, and then the micro-com 40 The reason for measuring RSSI is that the terminal is located in the weak field when the RSSI value is below a certain limit, and in this state, the audible supervisory tone (SAT) The quality of the audible supervision tone transmitted from the terminal to the base station deteriorates, making it difficult for both sides to detect the audible supervision tone, so that the fade timer almost acts as full. If the transmission path is interrupted by the function, the call path is likely to be completely blocked.

Therefore, in the weak electric field, the VOX function should be stopped and switched to continuous transmission (Normal Mode), and when the value of the A / D converter 21 is above a certain limit (a strong electric field of -90 to -100 dBm) (T5), The micro-comm 40 starts to operate the VOX. At that time, if there is a voice input A (T6), the transmission ON, which is the output terminal E of the micro-com 40, is continued until the voice input A becomes the low L level (until the sound is interrupted). The transmission is performed while keeping the on / off control line at a high level (T10).

The above process will be described with reference to the timing diagram shown in FIG.

First, when a voice signal (audio level) as shown in FIG. 4 (a) is output through the microphone amplifier 11, it is applied to the detector 10 to be detected, and then the detected tone is a resistor ( After charging by R5) and capacitor C2, the non-inverting terminal shaft potential of comparator U2 is raised.

In addition, in order to prevent malfunction due to background noise, an appropriate bias voltage is applied to the inverting terminal side of the comparator U2. The bias potential and the non-inverting terminal side potential are compared, and high (H) as shown in FIG. ) Output value A is output, and this output value A is input to the input terminal of the microcomputer 40.

When the value (A) is input, the micro-com 40 turns on the transmission line and transmits data to the base station through the antenna.

At this time, when the transmission on / off timing diagram shown in FIG. 3 (d) is shown in the transmission process, it can be seen that the transmission time occupies a slightly longer period than the timing diagram showing the detection of the tone in FIG. 3 (c). The reason is that in fact, when a person talks, there is not a sound at every moment, but there is a silence period. If you continue to transmit without any measures in this state, the actual transmission process takes time. The listener (the other side) hears the sound as a phenomenon that the sound continues and ends, that is, the intermittent phenomenon.

Therefore, to prevent this, it is the timer for preventing inter-syllable intermittent syllables (TC) that keeps the sound soft, and also retriggers for about 100 ~ 200msec by software so that the passage is not easily blocked at each syllable part of the voice. There is a slight delay because it triggers a retriggerable delay.

On the other hand, if you continue the call in the above situation, there is no problem. In the case where the VOX mode function is not provided, the person who uses the terminal only listens to the call without transmitting (continued with the transmission circuit). If not in use), the battery voltage supplied to the transmission line is wasted.

To compensate for this, when the voice is interrupted as in the silent part of FIG. 3 (a) and the voice input A is changed to the low level as in the silent part of FIG. 3 (c), the micro-com 40 repeats RSSI. After checking, if it is confirmed that the terminal is still in the strong electric field, after confirming that the syllable syllable prevention timer TC is reset, if it is in the reset state, the maximum transmission stop time setting timer TB is set to 3 seconds. At the same time, the output of the transmission on / off control line E is set at a low level, and transmission is interrupted for the period indicated by TB 3 seconds in FIG. 3 (d) (T7, T8).

(For reference, the function of the maximum transmission stop time setting timer (TB) will be described. When the VOX function is executed in the terminal itself when the VOX mode is not serviced in the base station, which is the subject of the present invention, the transmission circuit is 5 seconds. As a timer set so as not to shut off abnormally, in the present invention, it was set to 3 seconds, and the reason for setting it within 5 seconds is as follows.

As mentioned above, when the base station supports the VOX function, when the base station and the terminal recognize the VOX mode state, even if the channel is blocked for a considerable time, that is, even if the SAT signal is not detected, the channel is not blocked. When the VOX function is executed in the terminal itself, the base station cannot know, so the SAT signal must be transmitted within 5 seconds after the last transmission. If the SAT signal is not detected for more than 5 seconds, the call is completely blocked and the call is disconnected. Because).

If the timer T for maximum transmission stop time setting is not reset in the above state (transmission interruption period) (T9), the RSSI check (T5) is continuously executed to determine the electric field and the comparator where the terminal is located. Whether the voice input A, the output of U2) is at high level (T6), whether the maximum transmission stop time setting timer TB is reset (T9) (reset after 3 seconds), and received from the base station It is checked whether or not a message that needs to be answered among the messages has been entered (T3).

This is to resume transmission immediately after each input is detected even if the maximum transmission stop time setting timer (TB) is not reset (if the transmission stop period is less than 3 seconds) (T10). When resumption, even if the transmission's continuity factor is eliminated, it should be transmitted for at least 2 seconds by the continuous operation of the SAT fade lock timer (TA) (T11, T12).

If the terminal user is using a mobile phone in the VOX mode supported by the present invention, when a very short tone (for example, "yes") occurs, the transmission time of the terminal is also shortened proportionally, and if so, the SAT of the base station This is because the transmission may be interrupted before the detector even detects the SAT.

Therefore, in order to prevent this, it is a timer that gives a slight delay time after the sound is generated so that accurate transmission is made, and the delay time can be arbitrarily adjusted (about 0.1 to 0.2 sec).

In contrast to the above case, even when the maximum transmission stop time setting timer TB is reset (when the transmission stop time is 3 seconds), the base station detects the SAT fade lock timer TA so that the SAT can be detected. Send immediately.

In addition, as shown in FIG. 3 (e), the time required for the phase lock of the SAT whose phase is out of phase due to the transmission device (TB 3 sec) is completely achieved by the SAT phase synchronization loop (PLL) 22. (The part indicated by TP in the drawing: SAT face lock correction time), which means that the elapsed time until the SAT output signal stage (C) becomes a high level due to the phase lock of the SAT phase locked loop 22 is achieved. If necessary, the SAT fade lock timer TA is set to 2 seconds and transmission continues with or without a transmission tone until the timer TA is reset. (FIG. 3 (d), (e)) (to prevent the passage of the passage).

At this time, when the timer (TB) for setting the maximum transmission stop time is set and operated, the fade timer is also operated as shown in section (e) of FIG. 3, followed by the SAT fade lock timer (TA). After the fade timer completes counting, the fade timer is set again by counting (fade timer reset (5 seconds)), and the fade timer is stopped while the SAT fade lock timer TA is running.

The fade timer is then activated again to prevent the call from being blocked during the SAT face lock correction period (TP). After the correction period, the fade timer is reset (fade timer reset).

When the transmission / reception returns to the normal state as described above, subsequent operations are terminated by the call termination message from the base station or the call termination request message of the user (for example, through the data phase synchronization loop (PLL) 23). The above operation is repeated until there is data shown in FIG. 3 (b) provided to the input terminal D of 40).

As described in detail above, the present invention divides the fade timer into a SAT fade lock timer (TA) and a maximum transmission stop time setting timer (TB). By unblocking the channel for a set time (approximately 3 seconds), you can extend the service life by suppressing power consumption of the terminal, and use the fade timer time, so that if there is no service of the VOX function in the system Even if the terminal itself performs the VOX function.

Claims (1)

A detector 10 for detecting the audio output from the microphone amplifier 11; A comparator U2 for comparing the output level of the detector 10 with the set bias voltage VB; A detector 20 for detecting a state of the receiver 12; The control unit 30 controls the transmitter 30 by checking the state of the comparator U2 and the detector 20, and includes a fade timer divided into a SAT fade lock timer (TA) and a maximum transmission stop time setting timer (TB). 2. The automatic transmission switching device for mobile communication, comprising: a com (40). The method according to claim 1, wherein the sensing unit (20) is an A / D converter for providing the RSSI of the receiving unit (12) to the micro-com ( 21) a SAT phase-locked loop 22 for turning on / off a voice (audio) signal and providing it to the microcomputer 40; An automatic transmission switching device for mobile communication, comprising a data phase synchronization loop (23) for controlling data and providing the data to the microcomputer (40).