current limiter for TIA, reducing the problem of distortion in over limit input
From the patent you cited,


  [0024] The function of the diode-connected transistor 52 is
  to supply additional current to the current source I1 during
  the overdrive condition. During the overdrive condition, the
  current source I1 in the exemplary circuit arrangement
  shoWn by the FIGURE requires a current of 1000\$\times\$10 uA or
  10 mA. 


In order for this to happen, you need to either use a p-channel JFET instead of n-channel, or you need to reverse the polarity of your input source (I1), so that it can draw current through the diode-connected FET when the overdrive occurs.

Basically, this circuit only works for one polarity of input current. That's okay, because a lot of typical use cases for TIA's (like amplifying photodetector signals) only involve one polarity of input current.


  even though the excess current is limited i want the waveform not to distort, kindly point out flaws in the design


This is not possible. A limiting circuit inherently introduces distortion into a signal. Imagine you input a large-amplitude sine wave into a limiting circuit. The output would be closer to a square wave. This is a textbook case of distortion, and is the expected and desired result when you use a limiting circuit.

Possibly you should consider an automatic gain control (AGC) amplifier instead of a limiter.