JP2013055373A5

JP2013055373A5 -

Info

Publication number: JP2013055373A5
Application number: JP2011190047A
Authority: JP
Filing date: 2011-08-31
Publication date: 2014-04-17
Anticipated expiration: 2031-08-31

Description

上記課題を解決するため、本発明に係るワイヤレスマイク用ＯＦＤＭ送信装置は、デジタルの音声信号をＯＦＤＭ変調方式により送信するワイヤレスマイク用ＯＦＤＭ送信装置であって、デジタルの音声信号をブロック単位で入力し、ブロックごとに内符号化して内符号を生成する内符号符号化部と、前記内符号をＯＦＤＭ変調方式により変調してＯＦＤＭ信号を生成するＯＦＤＭ変調部と、前記内符号符号化部に入力されるブロック単位のデータのビット数をＮｏ、前記内符号の符号化率をＲｉ、前記ＯＦＤＭ信号の変調多値数をＭ、前記ＯＦＤＭ信号のデータキャリア数をＮｄとしたとき、ＯＦＤＭ信号のシンボル長が音声信号のサンプリング間隔の整数倍となるように、前記Ｎｏ，前記Ｒｉ，前記Ｍ，及び前記Ｎｄを設定する送信パラメータ設定部と、を備えることを特徴とする。 In order to solve the above problems, an OFDM transmitter for a wireless microphone according to the present invention is an OFDM transmitter for a wireless microphone that transmits a digital audio signal by an OFDM modulation method, and inputs the digital audio signal in units of blocks. An inner code encoder that generates an inner code by performing inner encoding for each block, an OFDM modulator that generates an OFDM signal by modulating the inner code using an OFDM modulation method, and an inner code encoder. that No the number of bits of data in block units, when the coding rate of the inner code Ri, M a modulation level of the OFDM signal, the number of data carriers of the OFDM signal was Nd, symbol O FDM signal A transmission parameter for setting the No, the Ri, the M, and the Nd so that the length is an integral multiple of the sampling interval of the audio signal. And a meter setting unit.

また、本発明に係るワイヤレスマイク用ＯＦＤＭ送信装置において、前記送信パラメータ設定部は、Ｎｏ＝Ｒｉ×Ｍ×Ｎｄとなるように、前記Ｎｏ，前記Ｒｉ，前記Ｍ，及び前記Ｎｄを設定することを特徴とする。また、前記送信パラメータ設定部は、ＯＦＤＭ信号の有効シンボル長が６６．６μｓ以上、且つ、２３０μｓ以下となるように、前記Ｎｏ，前記Ｒｉ，前記Ｍ，及び前記Ｎｄを設定することを特徴とする。 In the wireless microphone OFDM transmitter according to the present invention, the transmission parameter setting unit sets the No, the Ri, the M, and the Nd so that No = Ri × M × Nd. Features. The transmission parameter setting unit may set the No, the Ri, the M, and the Nd so that an effective symbol length of the OFDM signal is 66.6 μs or more and 230 μs or less. .

Claims

An OFDM transmitter for a wireless microphone that transmits a digital audio signal by an OFDM modulation method,
An inner code encoder that inputs a digital audio signal in units of blocks and performs inner encoding for each block to generate an inner code;
An OFDM modulator that modulates the inner code using an OFDM modulation scheme to generate an OFDM signal;
The number of bits of block unit data input to the inner code encoder is No, the coding rate of the inner code is Ri, the modulation multi-level number of the OFDM signal is M, and the number of data carriers of the OFDM signal is Nd. and when the O symbol length FDM signal to be an integral multiple of the sampling interval of the audio signal, the No, the Ri, transmission parameter setting the M, and the Nd setting unit,
An OFDM transmitter for a wireless microphone, comprising:

2. The wireless microphone OFDM according to claim 1, wherein the transmission parameter setting unit sets the No, the Ri, the M, and the Nd so that No = Ri × M × Nd. Transmitter device.

The transmission parameter setting unit sets the No, the Ri, the M, and the Nd so that an effective symbol length of the OFDM signal is 66.6 μs or more and 230 μs or less. Item 3. The wireless microphone OFDM transmitter according to Item 1 or 2 .

And further comprising an outer code encoder that performs block encoding on the digital audio signal to generate an outer code,
The inner code encoding unit generates an inner code by inner encoding the outer code generated by the outer code encoding unit, and the transmission parameter setting unit sets the number of bits of the code length of the outer code as No. The OFDM transmitter for a wireless microphone according to any one of claims 1 to 3, wherein:

The transmission parameter setting unit is configured such that when the encoding rate of the outer code is Ro, the values of Ro, Ri, M, and Nd are constant regardless of the parameter setting mode. The OFDM transmitter for wireless microphone according to claim 4 , wherein the M and the Nd are set.

6. The wireless microphone OFDM transmission apparatus according to claim 5 , wherein the transmission parameter setting unit sets the Ro and the No so that the Ro is constant and the No is constant.

An OFDM receiver for a wireless microphone, which receives the OFDM signal transmitted by the OFDM transmitter for a wireless microphone according to any one of claims 1 to 6 and generates a digital audio signal.