Abstract:
In response to continuous operation of an operation key on a remote control transmitter, the transmitter repetitively transmits a corresponding remote control signal with a predetermined cyclic period. The signal is received and analyzed by a remote control receiver and transmitted via a wired transmission path to a remote control re-transmitter. Then, the signal is re-transmitted by the re-transmitter via the wired transmission path. Due to a low transmission speed of the transmission path, the transmission path can not transmit all data of the remote control signal to the re-transmitter. Thus, until the next data are received from the transmission path, the re-transmitter interpolates the remote control signal based on the last data, and repetitively transmits the interpolated signal with the predetermined cyclic period.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a wireless remote control signal transfer method and apparatus and wireless remote control system which transfer a wireless remote control signal, transmitted from an wireless remote control transmitter, to to-be-operated-equipment (hereinafter referred to as “operated equipment”) via a wired transmission path so as to remote-control the operated equipment, and more particularly to a technique for achieving a corresponding function of the operated equipment responsive to so-called “continuous depressing operation” on the remote control transmitter. 
         [0002]    Among audio reproduction systems known today are ones of the type where an reproduction apparatus, including for example a CD player, amplifier, etc., is positioned in a single room and speaker cables connected to the reproduction apparatus are laid in a plurality of rooms so that audio signals can be audibly reproduced in the individual rooms. Example of such an audio reproduction system is disclosed in Japanese Patent Application Laid-open Publication No. 2003-45166. 
         [0003]      FIG. 2  shows an example general system setup employed for remote-controlling a reproduction apparatus from individual rooms in the aforementioned audio reproduction system. Infrared remote control system  10  of  FIG. 2  includes an infrared remote control transmitter  12  and infrared remote control receiver  14  positioned in a room A, and an infrared remote control re-transmitter  16  and operated equipment (i.e., reproduction apparatus)  18  positioned in another room B. The infrared remote control receiver  14  and infrared remote control re-transmitter  16  are connected with each other via a wired transmission path  20 . The operated equipment  18  is constructed to operate by directly receiving an infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 . In this infrared remote control system  10 , however, the operated equipment  18  can not be directly operated or controlled by the infrared remote control transmitter  12  because the infrared remote control transmitter  12  and operated equipment  18  are positioned in the different rooms A and B. Thus, in the system of  FIG. 2 , the infrared remote control receiver  14  and infrared remote control re-transmitter  16  are provided in the room A and B, respectively, and these receiver  14  and re-transmitter  16  are connected with each other via the wired transmission path  20 , comprising an electric cable or optical cable, to thereby constitute an infrared remote control signal transfer apparatus  26 . With such an infrared remote control signal transfer apparatus  26 , the infrared remote control signal  22  of the infrared remote control transmitter  12  can be transferred to the operated equipment  18  via the infrared remote control signal transfer apparatus  26 . 
         [0004]    Namely, in the infrared remote control system  10 , the infrared remote control transmitter  12  transmits an infrared remote control signal  22  responsive to or corresponding to user&#39;s operation of an operation key, such as a push button. The infrared remote control receiver  14  receives the infrared remote control signal  22  from the transmitter  12 , analyzes a train of bits of the received control signal  22  and transmits code analysis data (e.g., data obtained by directly converting the bit train into numerical values)  23  to the wired transmission path  20 . The infrared remote control re-transmitter  16  receives the code analysis data  23  from the transmission path  20 , reproduces an infrared remote control signal  24  (i.e., signal corresponding to the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 ) by modulating the bit train, corresponding to the code analysis data  23 , with a predetermined carrier wave and then transmits the reproduced infrared remote control signal  24 . The operated equipment  18  receives and analyzes the infrared remote control signal  24  and performs a process corresponding to the result of the analysis (i.e., process instructed by the infrared remote control transmitter  12 ). 
         [0005]    Among various operational functions by the conventionally-known infrared remote control transmitters is the so-called “continuous depression function”, which is intended to cause desired operated equipment to perform a special function in response to a user continuously performing one particular operation (i.e., “continuous depressing operation”) on the infrared remote control transmitter. For example, the continuous depression function can be used as a function to gradually increase a volume-up (i.e., volume-increasing) or volume-down (volume-decreasing) speed of an amplifier in accordance with the passage of time, if the user continues to depress a volume-up or volume-down button on the infrared remote control transmitter. The continuous depression function can also be used as a function to gradually increase a fast-forwarding or fast-rewinding speed of an amplifier in accordance with the passage of time, if the user continues to depress a fast-forward or fast-rewind button of a CD player or video player via the infrared remote control transmitter. 
         [0006]    If the user continues to depress any one of the buttons of the infrared remote control transmitter in order to perform the continuous depression function, the infrared remote control transmitter repetitively transmits an infrared remote control signal, corresponding to the depressing operation, with a predetermined cyclic frame period as long as the button is depressed. During that time, the operated equipment detects that the infrared remote control signal is repetitively received from the transmitter with the predetermined cyclic period and thereby determines that a continuous depression function is being instructed, so that it performs a predetermined process, preset set as the continuous depression function of the depressed button, as long as the reception of the infrared remote control signal lasts. 
         [0007]    The infrared remote control system  10  of  FIG. 2  can be constructed in such a manner that transmission of the code analysis data  23  of the infrared remote control signal  22  and other data (e.g., audio signal data) is carried out simultaneously using the wired transmission path  20 . In such a case, a plurality of data are subjected to multiplexing (such as time-division multiplexing or frequency multiplexing), and the resultant multiplexed data are transmitted to the wired transmission path  20 . Because the transmission of the code analysis data  23  is carried out utilizing an empty time or empty band, it may sometimes become impossible to secure a sufficient speed for transmission of the code analysis data  23 . 
         [0008]    Let it be assumed here that the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12  has a frame length T 0  that is, for example, 108 msec. and that a time T 1  is required to transmit, via the wired transmission path  20 , the code analysis data  23  of one frame of the infrared remote control signal  22 . If the user performs continuous depressing operation on the infrared remote control transmitter  12 , the transmitter  12  repetitively transmits, as the infrared remote control signal  22 , code data C 0 , C 1 , C 1 , . . . (here, C 0  is an operation code and C 1  is a repeat code) or code data C 0 , C 0 , C 0 , . . . with a cyclic period equal to the frame length T 0 . If, during that time, the operated equipment  18  has received the next code (i.e., repeat code C 1  or same code as the last operation code C 0 ) within a time period T 0 +α (α is a leeway time preset in view of possible variation or difference in time management between different operated equipment) after the beginning of the reception of the operation code C 0 , the operated equipment  18  determines that the same operation key is being continuously operated. If, on the other hand, the operated equipment has not received the next code within the time period T 0 +α, the operated equipment  18  normally determines that the key operation has been terminated. Thus, in a case where T 1 &gt;T 0 +α, even if continuous depressing operation has been performed by the user on the infrared remote control transmitter  12 , the infrared remote control re-transmitter  16  can not transmit an infrared remote control signal  22  of the next code within the time period T 0 +α following the transmission of the infrared remote control signal  22  of the leading operation code C 0 . As a result, the operated equipment  18  can not detect the continuous depressing operation, and thus, it can not perform a process corresponding to the continuous depressing operation. 
       SUMMARY OF THE INVENTION 
       [0009]    In view of the foregoing, it is an object of the present invention to provide an improved wireless remote control signal transfer method and apparatus and wireless remote control system which, even where a transmission speed of a wired transmission path is relatively low, allows operated equipment to perform a function corresponding to continuous depressing operation on an wireless remote control transmitter. 
         [0010]    In order to accomplish the above-mentioned object, the present invention provides an improved wireless remote control signal transfer method, which comprises: a reception step of receiving an wireless remote control signal repetitively transmitted by an wireless remote control transmitter with a first cyclic period while one given operation is being continuously performed on the wireless remote control transmitter; a step of analyzing the wireless remote control signal, received by the reception step, to provide code analysis data of the wireless remote control signal and repetitively transmitting the code analysis data of the wireless remote control signal to a wired transmission path with a second cyclic period, longer than the first cyclic period, as long as the reception of the wireless remote control signal lasts with the first cyclic period; a re-transmission step of receiving the code analysis data from the wired transmission path and repetitively re-transmitting an wireless remote control signal, corresponding to the received code analysis data and also representing the wireless remote control signal transmitted by the wireless remote control transmitter, with the first cyclic period as long as the reception of the code analysis data lasts with the second cyclic period; and a step of causing the wireless remote control signal, re-transmitted by the re-transmission step, to be received by operated equipment (such as a reproduction apparatus) remote-controlled by the wireless remote control signal transmitter. 
         [0011]    According to another aspect of the present invention, there is provided an improved wireless remote control signal transfer apparatus including an wireless remote control receiver, an wireless remote control re-transmitter, and a wired transmission path interconnecting the wireless remote control receiver and the wireless remote control re-transmitter. Here, the wireless remote control receiver receives an wireless remote control signal repetitively transmitted by an wireless remote control transmitter with a first cyclic period while one given operation is being continuously performed on the wireless remote control transmitter. The wireless remote control receiver also analyzes the received wireless remote control signal to provide code analysis data of the wireless remote control signal and transmits the code analysis data of the wireless remote control signal to the wired transmission path with a second cyclic period, longer than the first cyclic period, as long as the reception of the wireless remote control signal lasts with the first cyclic period. Further, the wireless remote control re-transmitter receives the code analysis data from the wired transmission path and repetitively re-transmits an wireless remote control signal, corresponding to the received code analysis data and also representing the wireless remote control signal transmitted by the wireless remote control transmitter, with the first cyclic period as long as the reception of the code analysis data lasts with the second cyclic period. 
         [0012]    Preferably, the wireless remote control receiver transmits, to the wired transmission path every the second cyclic period, the code analysis data of the wireless remote control signal received immediately before transmission, of the code analysis data, to the wired transmission path. 
         [0013]    Preferably, while the wireless remote control re-transmitter is continuously receiving the code analysis data from the wired transmission path with the second cyclic period, the wireless remote control re-transmitter repetitively re-transmits, with the first cyclic period and a particular number of times, an wireless remote control signal, corresponding to newest received code analysis data and also representing the wireless remote control signal transmitted by the wireless remote control transmitter, within a particular time period prior to receipt of next code analysis data and following re-transmission of the wireless remote control signal based on the code analysis data received immediately before the newest received code analysis data. The “particular number of times” corresponds, at a maximum, to a quotient obtained by diving the second cyclic period by the first cyclic period. 
         [0014]    Preferably, while one given operation is being continuously performed on the wireless remote control transmitter and when the wireless remote control re-transmitter has received the code analysis data of an operation code of a leading frame of an wireless remote control signal of a type where a repeat code is repetitively transmitted in and after a second frame following the operation code of the leading frame, the wireless remote control re-transmitter re-transmits the operation code in a leading frame and repetitively re-transmits the repeat code in and after a second frame. Further, while one given operation is being continuously performed on the wireless remote control transmitter and when the wireless remote control re-transmitter has received the code analysis data of an operation code of the leading frame of an wireless remote control signal of a type where an operation code is repetitively transmitted in all frames, the wireless remote control re-transmitter re-transmits the operation code in all frames. 
         [0015]    According to still another aspect of the present invention, there is provided an improved wireless remote control system, which comprises: an wireless remote control transmitter that transmits an wireless remote control signal responsive to operation by a user; an wireless remote control receiver that analyzes the wireless remote control signal, transmitted by the wireless remote control transmitter, to provide code analysis data of the wireless remote control signal and transmits the code analysis data of the wireless remote control signal to a wired transmission path; an wireless remote control re-transmitter that receives the code analysis data transmitted to the wired transmission path and transmits an wireless remote control signal, corresponding to the received code analysis data and also representing the wireless remote control signal transmitted by the wireless remote control transmitter; and operated equipment to be remote-controlled via the wireless remote control transmitter, the operated equipment analyzing the wireless remote control signal transmitted by the wireless remote control re-transmitter and performing a process corresponding to an analysis result of the wireless remote control signal. Here, while one given operation is being continuously performed on the wireless remote control transmitter and when the wireless remote control receiver has received an wireless remote control signal repetitively transmitted by the wireless remote control transmitter with a first cyclic period, the wireless remote control receiver transmits code analysis data of the wireless remote control signal to the wired transmission path with a second cyclic period longer than the first cyclic period. Further, when the wireless remote control re-transmitter has received the code analysis data transmitted to the wired transmission path, the wireless remote control re-transmitter transmits the wireless remote control signal corresponding to the received code analysis data and also repetitively transmits the wireless remote control signal with the first cyclic period for a time period up to immediately before a predetermined time corresponding to the second cyclic period passes after receipt of the code analysis data. 
         [0016]    Preferably, the wireless remote control receiver combines the code analysis data and other data than the code analysis data to thereby provide a multiplexed signal and transmits the multiplexed signal to the wired transmission path, and the wireless remote control re-transmitter extracts the code analysis data from the multiplexed signal received from the wired transmission path. 
         [0017]    According to the present invention thus arranged, even where the wired transmission path is capable of only transmitting code analysis data with a cyclic period longer than a cyclic period of an wireless remote control signal repetitively transmitted in response to continuous depressing operation on the wireless remote control transmitter, an wireless remote control signal, representing the wireless remote control signal transmitted by the wireless remote control transmitter, is repetitively re-transmitted for interpolation on the basis of the code analysis data received from the wired transmission path. As a result, the present invention allows the operated equipment to reliably perform a desired process corresponding to the continuous depressing operation. 
         [0018]    The following will describe embodiments of the present invention, but it should be appreciated that the present invention is not limited to the described embodiments and various modifications of the invention are possible without departing from the basic principles. The scope of the present invention is therefore to be determined solely by the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    The present invention is applicable to a wireless remote control system utilizing radio communication control such as Bluetooth and particularly is useful when applied to an infrared remote control system. 
           [0020]    For better understanding of the objects and other features of the present invention, its preferred embodiments will be described hereinbelow in greater detail with reference to the accompanying drawings, in which: 
           [0021]      FIG. 1  is a diagram explanatory of behavior based on control of  FIGS. 6 and 7  in a case where a pattern of code data transmitted from a remote control transmitter in response to continuous depressing operation is C 0 , C 1 , C 1 , . . . ; 
           [0022]      FIG. 2  is a block diagram showing an example general setup of an infrared remote control system to which is applied the present invention; 
           [0023]      FIG. 3  is a diagram explanatory of an infrared remote control signal; 
           [0024]      FIG. 4  is a block diagram showing an example construction of an infrared remote control receiver shown in  FIG. 2 ; 
           [0025]      FIG. 5  is a block diagram showing an example construction of an infrared remote control re-transmitter shown in  FIG. 2 ; 
           [0026]      FIG. 6  is a flow chart showing control performed by a CPU of the infrared remote control receiver of  FIG. 4 ; 
           [0027]      FIG. 7  is a flow chart showing control performed by a CPU of the infrared remote control re-transmitter of  FIG. 5 ; and 
           [0028]      FIG. 8  is a diagram explanatory of behavior based on the control of  FIGS. 6 and 7  in a case where a pattern of code data transmitted from the remote control transmitter in response to continuous depressing operation is C 0 , C 0 , C 0 , . . . . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    Now, a description will be given about an embodiment of the present invention in relation to a case where the invention is carried out in the infrared remote control system  10  of  FIG. 2 . First, an infrared remote control signal  22  transmitted from the infrared remote control transmitter  12  employed in the instant embodiment is explained. If a user operates a desired operation key on the infrared remote control transmitter  12 , the transmitter  12  transmits an infrared remote control signal  22  generated by modulating an operation code C 0 , corresponding to the operated key, with a carrier waveform of a predetermined frequency (e.g., 35 kHz). As shown in (a) of  FIG. 3 , one frame of the operation code C 0  comprises a leader portion, data portion and trailer (or stop) portion. The data portion comprises data corresponding to the operated key. The frame has a length of about 108 msec. 
         [0030]    If the user continuously depresses an operation key, corresponding to a continuous depressing operation function, on the infrared remote control transmitter  12 , the transmitter  12  repetitively transmits, following the transmission of the leading operation code C 0 , an infrared remote control signal  22 , generated by modulating a repeat code C 1  with the aforementioned carrier wave, with the frame period as long as the continuous depressing operation lasts. As shown in (b) of  FIG. 3 , one frame of the repeat code C 1  comprises only a leader portion and trailer (or stop) portion, with no data portion. The infrared remote control transmitter  12  may sometimes be of a type which repetitively transmits the operation code C 0  (without transmitting the repeat code C 1 ) even in and after the second frame. 
         [0031]      FIG. 4  shows an example construction of the infrared remote control receiver  14  employed in the instant embodiment. Infrared receiving unit  28  receives an infrared remote control signal  22  transmitted from the infrared remote control transmitter  12  and demodulates the received signal. Code data (train of bits) obtained by the demodulation are transmitted to a CPU (Central Processing Unit)  30 . The CPU  30  converts the code data into numerical value data of several bytes per frame. Specifically, the conversion into the numerical value data is carried out, for example, by dividing the bit train of the code data of each frame into groups each having a predetermined number of bits (e.g., four bits) and converting the code data of each of the divided groups into numerical value data (e.g., hexadecimal numbers). 
         [0032]    The numerical value data of each of the frames, generated by the CPU  30 , are sent, as code analysis data  23 , to a transmission path interface  32 . The transmission path interface  32  converts the code analysis data  23  into a format capable of being transmitted via the wired transmission path  20  and then sends the thus-converted code analysis data to the wired transmission path  20 . Where the same wired transmission path  20  is used for both transmission of the code analysis data of the infrared remote control signal  22  and transmission of other data (e.g., audio signal data), the transmission path interface  32  mixes (e.g., time-division multiplexes or frequency-multiplexes) the code analysis data of the infrared remote control signal  22  and the other data and then sends the thus-mixed (or multiplexed) data to the wired transmission path  20 . The wired transmission path  20  may be in the form of dedicated signal lines (electric cable or optical cable) for transmitting the code analysis data  23 , or in the form of indoor power lines for transmitting the code analysis data  23  by the so-called power line communication (PLC) scheme. 
         [0033]      FIG. 5  shows an example construction of the infrared remote control re-transmitter  16  employed in the embodiment. Transmission path interface  33  of the re-transmitter  16  receives the signal transmitted via the wired transmission path  20 , extracts the code analysis data  23  from the received signal and sends the thus-extracted code analysis data to a CPU  34 . In the case where the same wired transmission path  20  is shared for both the transmission of the code analysis data  23  of the infrared remote control signal  22  and the transmission of other data, the transmission path interface  33  separates the code analysis data  23  of the infrared remote control signal  22  and the other data out of the received signal, and then it sends the separated code analysis data  23  of the infrared remote control signal  22  to the CPU  34 . The CPU  34  restores corresponding code data (i.e., train of bits)  35  (i.e., the same code data of the operation code C 0  or repeat code C 1  as those included in the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 ) from the code analysis data  23  and sends the restored code data to an infrared emitting unit  36 . The infrared emitting unit  36  AM-modulates the code data  35  with a carrier wave of the same frequency of the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 , and it then drives an infrared emitting diode with the modulated signal. As a result, an infrared remote control signal  24 , which is identical to the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 , is reproduced and transmitted from the infrared emitting unit  36 . 
         [0034]    Next, a description will be given about control performed by the infrared remote control receiver  14  and infrared remote control re-transmitter  16 . The following paragraphs first describe a case where the infrared remote control transmitter  12  is of a type which, in response to continuous operation of an continuously-depressable operation key (e.g., volume-up/down button), transmits an infrared remote control signal  22 , generated by modulating code data C 0 , C 1 , C 1 , . . . as shown in (a) of  FIG. 1 , with a predetermined cyclic period (i.e., first cyclic period of, for example, 108 msec.) T 0 , as shown in (a) of  FIG. 1 , as long as the continuous depressing operation lasts. 
         [0035]    First, control performed by the CPU  30  of the infrared remote control receiver  14  of  FIG. 4  is described with reference to  FIG. 6 . The infrared remote control receiver  14  transmits code analysis data  23  of one frame of the infrared remote control signal  22  to the wired transmission path  20  with a cyclic period (i.e., second cyclic period) T 1  longer than the transmission period T 0  of the infrared remote control signal  22 , as shown in (b) of  FIG. 1 . Upon receipt of demodulated code data from the infrared receiving unit  28  (step S 1 ), the CPU  30  performs a process for converting the received signal into numerical value data on a frame-by-frame basis (step S 2 ). Once the numerical value data (i.e., code analysis data  23 ) of one frame are obtained (step S 3 ), the CPU  30  stores the code analysis data  23  into a transfer standby buffer memory (not shown) (step S 4 ). 
         [0036]    When the time T 1  or more has passed after the last transmission, to the wired transmission path  20 , of the code analysis data  23  (S 5 ) and if the code analysis data  23  are currently stored in the transfer standby buffer memory (S 6 ), the code analysis data  23  are read out from the transfer standby buffer memory (S 6 ) and transferred to the wired transmission path  20  via the transmission path interface  32  (step S 7 ). If code analysis data  23  of the next frame are acquired prior to the passage of the time T 0  after the acquisition of the code analysis data  23  of the last frame, the transfer standby buffer memory is updated with the code analysis data  23  of the next frame (steps S 1 , S 2 , S 3 , and S 4 ). If, on the other hand, the code analysis data  23  of the next frame are not acquired or established prior to the passage of the time T 0  after the acquisition of the code analysis data  23  of the last frame (step S 8 ), the transfer standby buffer memory is cleared (step S 9 ). 
         [0037]    If continuous depressing operation is performed on the infrared remote control transmitter  12 , and when a corresponding infrared remote control signal  22  has been received by the infrared remote control receiver  14 , the leading operation code C 0  of the signal is analyzed and then resultant code analysis data  23  are stored into the above-mentioned transfer standby buffer memory (step S 4 ). Then, the code analysis data  23  are read out from the transfer standby buffer memory (steps S 5  and S 6 ) and transmitted to the wired transmission path  20  via the transmission path interface  32  (step S 7 ). Once the time T 0  passes after the analysis of the leading operation code C 0 , the repeat codes C 1  of the second and subsequent frames are analyzed at intervals of the time T 0 , so that the transfer standby buffer memory is updated with the code analysis data  23  every predetermined time T 0  (S 1 , S 2 , S 3  and S 4 ). Then, once the time T 1  passes from the last transmission (step S 7 ), to the wired transmission path  20 , of the code analysis data (step S 5 ), the code analysis data  23  stored in the transfer standby buffer memory at that time (i.e., code analysis data of the repeat code C 1 ) are read out (step S 6 ) and transmitted to the wired transmission path  20  via the transmission path interface  32  (step S 7 ). In the aforementioned manner, the code analysis data of the code data C 0 , C 1 , C 1 , . . . are sequentially transmitted from the infrared remote control receiver  14  to the wired transmission path  20  as shown in (b) of  FIG. 1  at intervals of the cyclic period T 1  as long as the continuous depressing operation lasts. Once the continuous depressing operation is terminated and the time T 0  passes after the establishment of the last frame (step S 3 ) (YES determination at step S 8 ), the transmission of the code analysis data  23  is brought to an end, and the transfer standby buffer memory is cleared (step S 9 ). 
         [0038]    Now, a description will be given about control performed by the CPU  34  of the infrared remote control re-transmitter  16  shown in  FIG. 5 . Once code analysis data  23  are received from the wired transmission path  20  (step S 11 ), and if the received code analysis data  23  are those of an operation code C 0 , the CPU  34  restores, from the code analysis data  23 , the corresponding operation code C 0  (i.e., the same operation code C 0  as included in the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 ) and then stores the restored operation code C 0  into a buffer memory (not shown) within the CPU  34  (steps S 12  and S 13 ). Then, upon passage of the time T 0  after the last transmission of the infrared remote control signal  24  (YES determination at step S 14 ), the operation code C 0  is read out from the buffer memory and transmitted, as code data  35 , to the infrared emitting unit  36  (step S 15 ). The infrared emitting unit  36  AM-modulates the transmitted operation code C 0  with a carrier wave and transmits the thus-modulated code as an infrared remote control signal  24 . 
         [0039]    If the code analysis data  23  received from the wired transmission path  20  are those of a repeat code C 1  (YES determination at step S 12 ), and when the time T 0  has passed after the last transmission of the infrared remote control signal  24  (YES determination at step S 16 ), the corresponding repeat code C 1  is transmitted to the infrared emitting unit  36  (S 17 ). Because the repeat code C 1  is a code common to each operation key, the repeat code C 1  is prestored in a not-shown memory within the infrared remote control re-transmitter  16 , so that the repeat code C 1  is read out and transmitted to the infrared emitting unit  36  when the repeat code C 1  is to be transmitted one or more times upon receipt of the code analysis data of the repeat code C 1  and prior to receipt of the first repeat code C 1  following receipt of the leading operation code C 0 . The infrared emitting unit  36  AM-modulates the repeat code C 1  with a carrier wave and transmits the thus-modulated code as an infrared remote control signal  24 . Therefore, when the code analysis data of the repeat code C 1  have been received, no operation is performed here for storing the repeat code C 1  into the buffer memory. 
         [0040]    After receiving the code analysis data  23  (S 11 ) and transmitting the operation code C 0 , corresponding to the received code analysis data, to the infrared emitting unit  36  (S 15 ), the CPU  34  performs the following operations in accordance with a type of the operation code C 0 . Namely, if the operation code C 0  is the operation code C 0  of the code pattern C 0 , C 1 , C 1 , . . . (i.e., operation code C 0  followed by repeat codes C 1 ) generated in response to continuous depressing operation, the CPU  34  reads out, from the not-shown memory, the repeat code C 1  as an interpolating code and sends the read-out codes to the infrared emitting unit  36  (step S 20 ) each time the time T 0  passes (step S 19 ). If the operation code C 0  is the operation code C 0  of the code pattern C 0 , C 0 , C 0 , . . . (i.e., operation code C 0  followed by operation codes C 0 ) generated in response to continuous depressing operation, the CPU  34  reads out, from, the buffer memory, the operation code C 0  as an interpolating code and sends the read-out code to the infrared emitting unit  36  (step S 20 ) each time the time T 0  passes (step S 19 ). 
         [0041]    In order to perform such case-specific control according to the type of the operation code C 0 , a memory (not shown) of the infrared remote control re-transmitter  16  has prestored therein information indicating which one of 1) the operation code C 0  of the code pattern C 0 , C 1 , C 1 , . . . (i.e., operation code C 0  followed by repeat codes C 1 ) generated in response to continuous depressing operation and 2) the operation code C 0  of the code pattern C 0 , C 0 , C 0 , . . . (i.e., operation code C 0  followed by operation codes C 0 ) generated in response to continuous depressing operation the operation code C 0  corresponding to the received code analysis data is. When the code analysis data  23  of the operation code C 0  have been received (step S 11 ), the CPU  34  performs the corresponding control with reference to the memory. 
         [0042]    If next code analysis data  23  have not been received before the time T 1  passes after the receipt of the code analysis data  23  as determined at step S 18 , the CPU  34  clears the buffer memory at step S 21 . 
         [0043]    When code analysis data  23  of code data C 0 , C 1 , C 1 , . . . have been sequentially sent from the infrared remote control receiver  14  to the wired transmission path  20  at intervals of the cyclic period T 1  in response to continuous depressing operation on the infrared remote control transmitter  12 , the CPU  34  first receives the code analysis data of the leading operation code C 0  (steps S 11  and S 12 ), then restores the corresponding operation code C 0  (i.e., the same operation code as included in the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 ) and then stores the restored operation code C 0  into the buffer memory within the CPU  34  (S 13 ). Then, upon passage of the time T 0  after the last transmission of the infrared remote control signal  24  as determined at step S 14 , the CPU  34  reads out the operation code C 0  from the buffer memory (step S 15 ) and transmits a corresponding remote control signal  24  via the infrared emitting unit  36 . 
         [0044]    The infrared remote control re-transmitter  16  does not receive the code analysis data of the repeat code C 1  before the time T 1  passes from the receipt of the code analysis data of the operation code C 0 . Thus, before the code analysis data of the repeat code C 1  are received, the CPU  34  reads out the repeat code C 1  as an interpolating code from the not-shown memory (step S 20 ) each time the time T 0  passes (step S 19 ) after the transmission of the operation code C 0  (step S 19 ), and then it transmits a corresponding remote control signal  24  via the infrared emitting unit  36 . Then, when the code analysis data of the repeat code C 1  have been received (step S 11 ), and upon passage of the time T 0  after the last infrared emission (step S 16 ), the CPU  34  reads out the repeat code C 1  from the not-shown memory (step S 17 ) and transmits a corresponding remote control signal  24  via the infrared emitting unit  36 . In this manner, code data C 0 , C 1 , C 1 , . . . are transmitted from the infrared remote control re-transmitter  16  at intervals of the cyclic period T 0 , as shown in (c) of  FIG. 1 , as long as the continuous depressing operation lasts. After termination of the continuous depressing operation, and upon passage of the time T 1  after the receipt of the last code analysis data C 1  (step S 18 ), the transmission of the repeat code C 1  as the interpolating code is terminated, the buffer memory is cleared (step S 21 ), and the transmission of the remote control signal  24  via the infrared emitting unit  36  is terminated. 
         [0045]    The following paragraphs describe control performed by the infrared remote control receiver  14  and infrared remote control re-transmitter  16  in the case where the infrared remote control transmitter  12  is of the type that transmits an infrared remote control signal  22 , generated by modulating code data C 0 , C 0 , C 0 , . . . , with the predetermined cyclic period T 0  during continuous depressing operation of a continuously-depressable operation key on the transmitter  12 .  FIG. 8  shows behavior based on the control of  FIGS. 6 and 7 . 
         [0046]    First, the control performed by the CPU  30  of the infrared remote control receiver  14  will be described with reference to  FIG. 6 . When an infrared remote control signal  22  generated in response to continuous depressing operation on the infrared remote control transmitter  12  has been received by the infrared remote control receiver  14 , the leading operation code C 0  is first analyzed, and then resultant code analysis data  23  of the operation code C 0  are stored into the transfer standby buffer memory (steps S 1 , S 2 , S 3  and S 4 ). Then, the code analysis data  23  are read out from the transfer standby buffer memory (steps S 5  and S 6 ) and transmitted to the wired transmission path  20  via the transmission path interface  32  (step S 7 ). Then, upon passage of the time T 0  after the analysis of the leading operation code C 0 , the operation codes C 0  in and after the second frames are analyzed every predetermined time T 0 , and the transfer standby buffer memory is updated, every predetermined time T 0 , with the code analysis data  23  with of the operation code C 0  (steps S 1 , S 2 , S 3  and S 4 ). Then, once the time T 1  passes after the last transmission of the code analysis data  23  (step S 7 ) to the wired transmission path  20  as determined at step S 5 , the code analysis data  23  of the operation code C 0  stored in the transfer standby buffer memory at that time are read out (step S 6 ) and transmitted to the wired transmission path  20  via the transmission path interface  32  (step S 7 ). In this manner, the code analysis data  23  of the code data C 0 , C 1 , C 1 , . . . are sequentially sent from the infrared remote control receiver  14  to the wired transmission path  20  at intervals of the cyclic period T 1 , as shown in (b) of  FIG. 8 , as long as continuous depressing operation lasts. After termination of the continuous depressing operation, and upon passage of the time T 0  (step S 8 ) after the establishment of the last frame (step S 3 ), the transmission of the code analysis data  23  is terminated, and the transfer standby buffer memory is cleared (step S 9 ). 
         [0047]    Next, the control performed by the CPU  34  of the infrared remote control re-transmitter  16  will be described with reference to  FIG. 7 . When the code analysis data  23  of the code data C 0 , C 1 , C 1 , have been sequentially sent from the infrared remote control receiver  14  to the wired transmission path  20  at intervals of the cyclic period T 1  in response to continuous depressing operation on the infrared remote control transmitter  12 , the code analysis data of the leading operation code C 0  are first received (S 11  and S 12 ), and the corresponding operation code C 0  (i.e., the same operation code C 0  as included in the infrared remote control signal  22  transmitted from the infrared remote control transmitter  12 ) is restored so that the restored operation code is stored into the buffer memory within the CPU  34  (step S 13 ). Then, upon passage of the time T 0  after the last transmission of the infrared remote control signal  24  (step S 14 ), the operation code C 0  is read out from the buffer memory and transmitted via the infrared emitting unit  36 . 
         [0048]    As note above, the infrared remote control re-transmitter  16  does not receive the code analysis data of the next operation code C 0  before the time T 1  passes after the receipt of the code analysis data of the operation code C 0 . Thus, before the code analysis data of the operation code C 0  are received, the CPU  34  reads out the operation code C 0  as an interpolating code from the buffer memory (step S 20 ) each time the time T 0  passes (step S 19 ) after the transmission of the operation code C 0  (step S 15 ), and then it transmits the corresponding infrared remote control signal  24  via the infrared emitting unit  36 . Then, after receipt of the next operation code C 0  (S 11 ), and upon passage of the time T 0  after the last infrared emission (S 16 ), the CPU  34  reads out the operation code C 0  from the buffer memory (S 17 ) and transmits the corresponding infrared remote control signal  24  via the infrared emitting unit  36 . In this manner, the code data C 0 , C 0 , C 0 , . . . are transmitted from the infrared remote control re-transmitter  16  at intervals of the cyclic period T 0  as shown in (c) of  FIG. 8 . After termination of the continuous depressing operation, and upon passage of the time T 1  from receipt of the last code analysis data C 1  (step S 18 ), the transmission of the operation code C 0  as the interpolating code is terminated, the buffer memory is cleared (step S 21 ), and the transmission of the remote control signal  24  via the infrared emitting unit  36  is terminated. 
         [0049]    According to the control of  FIG. 7 , when the human operator has operated an operation key corresponding to the continuous depressing operation function, the repeat code C 1  or operation code C 0  will be transmitted, from the infrared remote control re-transmitter  16 , as an interpolating code, a particular number of times that correspond, at a maximum, to a quotient of T 1 /T 0  (i.e., an integral number m satisfying (m+1)T 0 &gt;T 1 &gt;mT 0 ), even if the operation of the key is not continuous depressing operation. Also, when the human operator has continuously operated an operation key corresponding to the continuous depressing operation function, repeat codes C 1  or operation codes C 0  are transmitted, from the infrared remote control re-transmitter  16 , as interpolating codes that correspond in number to the integral number m at a maximum. However, in either case, unless the integral number m is a very great value (i.e., unless the time T 1  is very long), the continuous depressing operation function does not last for a long time on the operated equipment  18  after termination of the operation of the key, so that the operation will not give any uncomfortable feeling to the user or human operator.