Digital transmission system with a double analog integrator Delta Sigma coder and a double digital integrator Delta Sigma decoder

In an analog to PCM coding and a PCM to analog decoding system, a Delta-Sigma noise-shaping codec operating at a sampling rate of substantially 2 MHz, said codec comprising:

• a Delta-Sigma noise-shaping coder including a single operational amplifier;
• an adding means receiving an analog signal and connected to said operational amplifier;
• two analog integrators in the feedback loop of said operational amplifier;
• a first and second cascaded flipflops operated at said sampling rate;
• a first resistor means connecting the output of said first flipflop to said adding means;
• a second resistor means connecting the output of said second flipflop to said adding means;
• and
• output means connected to said second flipflop;
• and
• a Delta-Sigma decoder including two digital integrators;
• an adding means receiving a digital signal coded by said coder and connected to said digital integrators;
• a first and second cascaded flipflops operating at said sampling rate;
• a first amplifier means connecting the output of said first flipflop to said adding means;
• a second amplifier means connecting the output of said second flipflop to said adding means;
• and
• output means connected to said second flipflop.