Artificial neural systems with dynamic synapses

• US 20030208451A1
• Filed: 05/05/2003
• Published: 11/06/2003
• Est. Priority Date: 05/03/2002
• Status: Abandoned Application

• Current Assignee: University of Southern California
• Original Assignee: University of Southern California
• Inventors: Liaw, Jim-Shih
• Application Number:
  US10/429,995
• Publication Number:
  US 20030208451A1
• Time in Patent Office: Days
• US Class Current: 706/8
• CPC Class Codes: G06N 3/049 Temporal neural networks, e.g. delay elements, oscillating neurons or pulsed inputs

Abstract

Artificial neural network systems where each signal processing junction connected between signal processing elements is operable to, in response to a received impulse action potential, operate in at least one of three permitted manners: (1) producing one single corresponding impulse, (2) producing no corresponding impulse, and (3) producing two or more corresponding impulse. A preprocessing module may be used to filter the input signal to such networks. Various control mechanism may be implemented.

Claims

1. An artificial neural network system, comprising a network of signal processing elements operating like neurons to process signals and a plurality of signal processing junctions distributed to interconnect said signal processing elements, said signal processing junctions operating like synapses,

wherein each signal processing junction is operable to process and is responsive to either or both of a non-impulse input signal and an input impulse signal from a neuron within said network, and each signal processing junction is operable to respond to a received impulse action potential in at least one of three permitted manners:

(1) producing one single corresponding impulse, (2) producing no corresponding impulse, and (3) producing two or more corresponding impulses.

2. The system as in claim 1, further comprising at least one signal path connected to one signal processing junction to send an external signal to said one signal processing junction, wherein said one signal processing junction is operable to respond to and process both said external signal and an input signal from a neuron in said network.

3. The system as in claim 2, wherein said external signal is one of a temporal signal, a spatial signal, and a spatio-temporal signal.

4. The system as in claim 1, further comprising a preprocessing module coupled to filter an input signal to said network, said preprocessing module comprising a plurality of filters of different characteristics operable to filter said input signal to produce filtered input signals to said network.

5. The system as in claim 4, wherein one of said filters is one of a bandpass filter, a highpass filter, a lowpass filter, a Gabor filter, a wavelet filter, a Fast Fourier Transform (FTT) filter, and a Linear Predictive Code filter.

6. The system as in claim 4, wherein two of said filters are filters based on different filtering mechanisms.

7. The system as in claim 4, wherein two of said filters are filters based on the same filtering mechanism but have different spectral properties.

8. The system as in claim 4, further comprising a first controller configured to control a filter configuration in said preprocessing module in response to a first control signal.

9. The system as in claim 8, further comprising:

a second controller configured to control said signal processing elements and said signal processing junctions in said network in response to at least one of an output from said preprocessing module and a second control signal; and

a third controller configured to control a filter configuration in said preprocessing module and said signal processing elements and said signal processing junctions in said network in response to at least one of an output from said network and a third control signal.

10. The system as in claim 9, further comprising an optimization module coupled to receive output signals from said first, said second, and said third controllers, and from said preprocessing module and said network, said optimization module operable to process said output signals to produce control signals to said first, said second, said third controllers, and said preprocessing module and said network.

11. The system as in claim 4, further comprising a second controller configured to control said signal processing elements and said signal processing junctions in said network in response to at least one of an output from said preprocessing module and a second control signal.

12. The system as in claim 4, further comprising a third controller configured to control a filter configuration in said preprocessing module and said signal processing elements and said signal processing junctions in said network in response to at least one of an output from said network and a third control signal.

13. The system as in claim 4, further comprising an optimization module coupled to receive an external signal generated outside said network, a first output signal from said preprocessing module, and a second output signal from said network, wherein said optimization module is operable to adjust a property of said network in response to said external signal, said first and said second output signals.

14. The system as in claim 1, further comprising an optimization module coupled to receive an external signal generated outside said network and an output signal from said network, wherein said optimization module is operable to adjust a property of said network in response to said external signal and said output signal.

15. An artificial neural network system, comprising:

a network of signal processing elements operating like neurons to process signals and a plurality of signal processing junctions distributed to interconnect said signal processing elements, said signal processing junctions operating like synapses, wherein each signal processing junction is operable to, in response to a received impulse action potential, operate in at least one of three permitted manners;

(1) producing one single corresponding impulse, (2) producing no corresponding impulse, and (3) producing two or more corresponding impulses; and

a preprocessing module to filter an input signal to said network, said preprocessing module comprising a plurality of filters of different characteristics operable to filter said input signal to produce filtered input signals to said network.

16. The system as in claim 15, further comprising:

a first controller configured to control a filter configuration in said preprocessing module in response to a first control signal;

a second controller configured to control said signal processing elements and said signal processing junctions in said network in response to at least one of an output from said preprocessing module and a second control signal; and

a third controller configured to control a filter configuration in said preprocessing module and said signal processing elements and said signal processing junctions in said network in response to at least one of an output from said network and a third control signal.

17. The system as in claim 16, further comprising an optimization module coupled to receive output signals from said first, said second, and said third controllers, and from said preprocessing module and said network, said optimization module operable to process said output signals to produce control signals to said first, said second, said third controllers, and said preprocessing module and said network.

18. The system as in claim 15, further comprising an optimization module coupled to receive an external signal generated outside said network, a first output signal from said preprocessing module, and a second output signal from said network, wherein said optimization module is operable to adjust a property of said network in response to said external signal, said first and said second output signals.

19. A method for signal processing, comprising:

filtering an input signal to produce multiple filtered input signals with different frequency characteristics; and

feeding the filtered input signals into a network of signal processing elements operating like neurons to process signals and a plurality of signal processing junctions distributed to interconnect the signal processing elements, said signal processing junctions operating like synapses, wherein each signal processing junction is operable to, in response to a received impulse action potential, operate in at least one of three permitted manners;

(1) producing one single corresponding impulse, (2) producing no corresponding impulse, and (3) producing two or more corresponding impulses.

20. The method as in claim 19, further comprising directing an external signal from a source outside the network to a signal processing junction and using the signal processing junction to process the external signal to produce an output to a neuron in the network.

21. The method as in claim 19, further comprising adjusting the filtering when processing different input signals.

22. The method as in claim 19, further comprising adjusting the filtering in response to an output of the network.

23. The method a sin claim 19, further comprising adjusting property of the network in response to an output of the network.