Digital data radio transmission system

A digital data radio transmission system for velocity-modulating input frame data, adding signals having a predetermined number of bits to said input frame data, and transmitting the resulting data as radio frame data, said system comprising:

• means for generating frame position pulses;
• writing means for dividing write clock pulses under control of the frame position pulses generated by said means for generating frame position pulses and for outputting the divided write clock pulses as write pulses;
• storing means for receiving said write pulses from said writing means and for temporarily storing said input frame data and said frame position pulses according to said write pulses and outputting output frame data and frame position pulses;
• timing pulse generating means for receiving said frame position pulses from said storing means and for outputting first and second control pulses in response to a supply of read clock pulses, the operation of said timing pulse generating means being controlled by said frame position pulses;
• reading means for dividing said read clock pulses by the same number as the write clock pulses under control of said first control pulses and for outputting the divided read clock pulses as read pulses to said storing means;
• and
• pulse inserting means for receiving the output frame data from said storing means and said second control pulses from said timing pulse generating means and for generating the radio frame data by inserting auxiliary pulses under control of said timing pulse generating means into the output frame data output from said storing means in response to said write pulses.