Telephone communications system increasing a reception count twofold

1. A telephone communications system having a function for receiving a multifrequency signal, comprising:

a quantizing device quantizing said multifrequency signal at a sampling frequency which is twice or more as large as a sampling frequency necessary for sampling said multifrequency signal to produce quantized data;

a low-pass filter low-pass filtering said quantized data at a cutoff frequency higher than a maximum frequency of said multifrequency signal to produce low-pass filtered data; and

a multifrequency signal receiver alternately performing an odd-numbered receiver processing and an even-numbered receiver processing on said low-pass filtered data,

wherein said multifrequency signal receiver comprises:

a numbering processing unit numbering said low-pass filtered data to produce numbered data with a data number;

a least significant bit discriminating unit discriminating a least significant bit of the data number added to said numbered data;

an even-numbered receiver processing performing unit performing the even-numbered receiver processing on said numbered data when the least significant bit of the data number is “0”; and

an odd-numbered receiver processing performing unit performing the odd-numbered receiver processing on said number data when the least significant bit of the data number is “1”.

2. The telephone communications system as claimed in claim 1 , wherein the sampling frequency of said quantizing device is 8 kHz or more.

3. The telephones communication system as claimed in claim 2 , wherein the cutoff frequency of said low-pass filter is equal to 2 KHz.

4. A method of receiving a multifrequency signal, comprising:

quantizing said multifrequency signal at a sampling frequency which is twice or more as large as a sampling frequency necessary for sampling said multifrequency signal to produce quantized data;

low-pass filtering said quantized data at a cutoff frequency higher than a maximum frequency of said multifrequency signal to produce low-pass filtered data; and

alternately performing an odd-numbered receiver processing and an even-numbered receiver processing on said low-pass filtered data,

wherein said performing of the receiver processing comprises:

numbering said low-pass filtered data to produce numbered data with a data number;

discriminating a least significant bit of the data number added to said numbered data;

performing the even-numbered receiver processing on said numbered data when the least significant bit of the data number “0”; and

performing the odd-numbered receiver processing on said number data when the least significant bit of the data number is “1”.

5. The method as claimed in claim 4 , wherein the sampling frequency in said quantizing is 8 kHz or more.

6. The method as claimed in claim 5 , wherein the cutoff frequency in said low-pass filtering is equal to 2 KHz.

7. A non-transitory computer readable recording medium for storing a program for use in a telephone communications system having a function of receiving a multifrequency signal, said telephone communications system comprising a quantizing device for quantizing said multifrequency signal at a sampling frequency which is twice or more as large as a sampling frequency necessary for sampling said multifrequency signal to produce quantized data, said program causing said telephone communications system to execute the steps of:

low-pass filtering said quantized data at a cutoff frequency higher than a maximum frequency of said multifrequency signal to produce low-pass filtered data; and

alternately performing an odd-numbered receiver processing and an even-numbered receiver processing on said low-pass filtered data,

wherein said performing step of the receiver processing comprises the steps of:

numbering said low-pass filtered data to produce numbered data with a data number;

discriminating a least significant bit of the data number added to said numbered data

performing the even-numbered receiver processing on said numbered data when the least significant bit of the data number is “0”; and

performing the odd-numbered receiver processing on said number data when the least significant bit of the data number is “1”.

8. The non-transitory computer readable recording medium as claimed in claim 7 , the sampling frequency of said quantizing device is 8 kHz or more, wherein the cutoff frequency in said low-pass filtering is equal to 2 KHz.

9. A non-transitory computer readable recording medium for storing a program for use in a telephone communications system having a function of receiving a multifrequency signal, said telephone communications system comprising a quantizing device for quantizing said multifrequency signal at a sampling frequency which is twice or more as large as a sampling frequency necessary for sampling said multifrequency signal to produce quantized data and a low-pass filter for low-pass filtering said quantized data at a cutoff frequency higher than a maximum frequency of said multifrequency signal to produce low-pass filtered data, said program causing said telephone communications system to execute the step of:

alternately performing an odd-numbered receiver processing and an even-numbered receiver processing on said low-pass filtered data,

wherein said performing step of the receiver processing comprises the steps of:

numbering said low-pass filtered data to produce numbered data with a data number;

discriminating a least significant bit of the data number added to said numbered data;

performing the even-numbered receiver processing on said numbered data when the least significant bit of the data number is “0”; and

performing the odd-numbered receiver processing on said number data when the least significant bit of the data number is “1”.