KR19990041639A - Sidetone suppression method in wireless telephone - Google Patents

Abstract

The present invention provides a method for suppressing sidetones in a radiotelephone having a plurality of portable devices registered in one fixed device in order to provide a more improved call function. It is characterized by controlling the condition, and detecting the user's voice transmission state and suppressing the level of the voice signal transmitted to the high frequency transmitter when the user's voice is output as a side tone.

Description

Sidetone suppression method in wireless telephone

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless telephone, and more particularly, to a method for suppressing sidetones in a wireless telephone.

Typically, a cordless telephone that is wired to a trunk line and wirelessly communicates with an extension is often referred to as a cordless telephone. Such a radiotelephone is composed of a fixed device and a plurality of portable devices. As is known, sidetone refers to a return tone that is heard back on your handset receiver during a call. In the related art, since the side tone is set by a hardware constant in the voice processing unit of the base set, the number of parts of the voice processing unit is large, and the circuit becomes complicated. There have been many problems in improving the sidetones.

Therefore, conventionally, there have been the above-mentioned problems in the transmission and improvement of sidetones.

Accordingly, an object of the present invention is to provide a sidetone control method that can simplify the number of components of a voice processing unit without setting by hardware constants, and can improve the call quality by reliably controlling the level and volume of sidetones. have.

Another object of the present invention is to provide an improved sidetone suppression method in a wireless telephone.

In order to achieve the above object, the present invention provides a method for suppressing sidetones in a wireless telephone having a portable device which is registered in a plurality of fixed devices. The control unit detects the user's voice transmission status and suppresses the level of the voice signal transmitted to the high frequency transmitter when the user's voice is output as a side tone.

Other objects and advantages of the invention will be apparent from the following description taken in conjunction with the accompanying drawings.

1 is a block diagram of a fixing device of a radiotelephone according to the present invention.

2 is a control block diagram of a fixing device and a portable device according to the present invention;

3 is a control flow diagram of sidetone suppression according to the present invention

A preferred embodiment of the present invention for a method of suppressing sidetones in a radiotelephone is described in detail.

1 is a block diagram of a fixing device for a radiotelephone according to the present invention, wherein the radiotelephone is commonly referred to as a digital European cordless telephone (DECT), and a digital RF transmitter / receiver 100, ABC DSP 120, speech IC 130, and a ring. A sensing unit 10, a keypad 150, and an EEPROM 140 as a memory. Among the digital signals received by the antenna, the new signal of the portable device is applied to the digital RF transmitter / receiver 100, filtered, multiplied and synthesized by various filter circuits therein, and the ABC DSP (ADPCM & BURST MODE CONTROLLER & MICRO CONTROLLER & DSP) 120 Is provided. The digital RF transmitter / receiver 100 synthesizes, multiplies and filters the digital signal provided by the ABC DSP 120 and transmits the digital signal to the antenna. The ABC DSP 120 analyzes the digital signal applied in units of slots when the synchronous data among the digital signals applied by the digital RF transmitter / receiver 100 are data set with a fixed device and ID. As a result of the analysis, the voice signal is converted into an analog signal and applied to the speech IC 130, and the storage data is stored in the memory 140. The ABC DSP 120, which responds to the input of the keypad 150, processes the analog voice signal applied from the voice IC 130 into a digital signal and outputs the digital voice signal to the digital RF transmitter / receiver 100 in units of slots. The ring detector 10 detects a ring signal when the telephone line is connected to a CO line and provides the MPU to the ABC DSP 120. The speech IC 130 is connected between a trunk line and the ABC DSP 120 to receive analog voice signals and various protocol signals provided from the telephone network of the trunk line and provide them to the ABC DSP 120. In addition, the analog voice signal and various protocol signals provided by the ABC DSP 120 are received and applied to the telephone network of the trunk line. The keypad 150 is an input unit having various keys such as a ten key and a function key. The user applies a paging input or various commands to the portable device through the keypad. The EEPROM 140 stores various kinds of information, program data, and ID data.

FIG. 2 is a block diagram of a controller of a fixing device and a portable device according to the present invention, which is a detailed view of the ABC DSP 120 of FIG. Burst Mode Logic (BML) 160 serves to provide various digital voice signals in the slot unit synchronized with the control of the MPU 200 and digital signals as control signals to the transmitter / receiver 100 of FIG. 1 or to output them to the SDR 170. . The System Data RAM (SDR) 170 has inbound and outbound buffers therein and temporarily stores ADPCM speech samples and inputs and outputs them under the control of the MPU 200. CODEC 190 is a function of coding or decoding a voice signal. Digital signal processing (DSP) 180 decimates the voice output data sample applied by the coder & decoder (CODEC) 190, interpolates the voice data applied by the SDR 170, removes echo, generates dual tone, mute, side Functions such as tone generation, volume control, automatic gain control, etc., perform general processing on digital signals. The MPU 200 controls overall call operation of the wireless telephone according to a preset program, and performs the sidetone suppression flow procedure of FIG. 3 in response to a key input according to the technical idea of the present invention.

3 is a control flowchart of the sidetone suppression method according to the present invention, and is shown in steps 30 to 37. When any mobile device is busy, the flow of function for sidetone removal in the fixed device is as follows. If the call is in the thirty-third state, but not in the thirty-third state, the call function is performed in the thirty-second step, and in step 33, the controller (MPU of FIG. If it is determined that the voice is not currently being transmitted, step 34 is performed. In step 34, the controller determines that the user is currently receiving the voice of the other party or the voice transmission / reception state is idle, and instructs the corresponding unit to deliver the size of the voice signal transmitted from the ABC chip 120 to the RF transmitter 100 as it is. do. In step 36, the controller determines that the call has ended and switches to the standby state in step 37. On the other hand, if it is determined in step 33 that the conversation state of the user during the call is in voice transmission of the user, step 35 is performed. In step 35, the controller instructs the corresponding unit to instruct or suppress the voice transmitted from the ABC chip 120 to the transmitter 100 below a predetermined level because the user is transmitting the voice during the voice call. Thus, the user hears the sound of a sign language for his or her voice as a side note in a suppressed or almost removed state. In step 36, when the user determines that the call is terminated, in step 37, the controller switches the system to the standby state and terminates the call. Accordingly, during voice transmission, a transmission path to the headset microphone-handset ABC chip-handset RF transmitter-base RF receiver 100-base ABC chip 120-base speech IC 130-line trunk line (C.O) is formed. In the case of voice reception, the reception path is performed in the order of the CO line-based speech IC 130- base ABC chip 120- base RF transmitter 100-handset RF receiver- handset ABC chip- handset speaker of a portable device. In such a loop state, the voice reception state is controlled to be normally heard during voice reception, but during voice transmission, the controller inside the base ABC chip senses the voice transmission state and cuts off the voice signal transmitted to the base RF transmitter inside the DSP. Suppresses sidetones during voice transmission.

Therefore, the user can hear the suppressed side tones for his voice and can make a call with improved quality.

As described above, the embodiment of the present invention has been described with respect to the method of suppressing sidetones during voice transmission, but various changes and modifications can be made within the range allowed by the matter.

According to the sidetone suppression method of the present invention, it is possible to simplify the number of parts of the voice processing unit without setting by hardware constant, and to improve the call quality by reliably controlling the level and volume of the sidetone. have.

Claims (2)

In the method of suppressing sidetones in a wireless telephone, when the voice of the other party of the user is output to the speaker, the control is performed according to a predetermined reception condition, and the user's voice is transmitted to the high frequency transmitter when the user's voice is output as the sidetone. Suppressing the level of the audio signal. A sidetone suppression method in a radiotelephone having a plurality of registered portable devices: Checking whether a busy conversation state is transmitting a voice of the user; And suppressing and outputting the voice transmitted from the signal processor to the high frequency transmitter below a predetermined level.