Loop filter for data converter in wireless communication system and method of implementing corresponding loop filter

A method of implementing a loop filter, the method comprising:

• forming a loop filter for a continuous time signal delta modulator (SDM), in a feedback loop structure;
• configuring the loop filter in the feedback loop structure to enable the loop filter to be entirely expressed by a first single transfer function
• substituting a feedforward loop structure for the loop filter in the feedback loop structure;
• and
• configuring the loop filter in the feedforward loop structure obtained through substitution to enable the loop filter to be entirely expressed by a second single transfer function.

A loop filter for a data converter in a wireless communication system, the loop filter comprising:

• third and first resistors sequentially connected to an input end;
• a second resistor, one end of which is connected to an inverting input end;
• first and second capacitors sequentially connected to between another end of the first resistor and an output end;
• a third capacitor connected to between the other end of the first resistor and the output end;
• a fourth capacitor connected to between another end of the second resistor and an inverting output end;
• and
• an operational amplifier configured to output an operational amplifier response to the output end, wherein an inverting end of the operational amplifier is connected to another end of the third resistor and a non-inverting end of the operational amplifier is connected to ground.

A method of implementing a loop filter, the method comprising:

• forming a loop filter for a third order continuous time SDM, in a feedback loop structure by using at least three operational amplifiers and capacitors;
• configuring the loop filter in the feedback loop structure to enable the loop filter to be entirely expressed by a first single transfer function;
• substituting a feedforward loop structure for the loop filter in the feedback loop structure;
• and
• configuring the loop filter in the feedforward loop structure obtained through substitution to enable the loop filter to be entirely expressed by a second single transfer function.