Transient and spurious signal filter

• US 10,348,418 B1
• Filed: 05/19/2015
• Issued: 07/09/2019
• Est. Priority Date: 07/22/2014
• Status: Active Grant

• Current Assignee: Esker Technologies, LLC
• Original Assignee: Esker Technologies, LLC
• Inventors: Olmstead, Brian S
• Primary Examiner(s): Hiltunen, Thomas J.
• Application Number:
  US14/716,380
• Time in Patent Office: 1,512 Days
• Field of Search: None
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04B 15/005 Reducing noise, e.g. humm, from the supply
• CPC Class Codes: H04B 3/542 the information being in digital form

Abstract

An improved filter for communications over a power bus may provide it to or minimize the effect of voltage spikes on a power line and/or may filter a power line signal with high pass and low pass filters to allow communicative signal reception on noisy power lines, and/or may filter a communicative signal transmitted from a radio modem with low pass filters to prevent high frequency harmonics and spurious signals from being conducted into and thereafter radiated from the power line.

Claims

1. An electrical circuit comprising:

a signal wire configured to conduct an electrical signal, said signal wire conducting power and communications and transient signals;

high-pass filter coupled to a transmitter and a receiver, said high-pass filter connected to the signal wire, the high-pass filter being capable of removing low-frequency components of the electrical signal below a predetermined low-frequency threshold;

a low-pass filter connected to the high-pass filter, the low-pass filter protected from transient signal a second clamp capable of clamping electrically fast transient pulse components of the electrical signal being capable of removing high-frequency components of the electrical signal above a predetermined high-frequency threshold;

a first voltage clamp connected to the low-pass filter, the first voltage clamp being capable of clamping a voltage level of the electrical signal at a maximum predetermined threshold voltage;

said second clamp protecting said low-pass filter from transient signals and,

a common mode choke protected from said transient signals by the first voltage clamp.

2. An electrical circuit according to claim 1, further comprising a radio modem coupled to the choke.

3. An electrical circuit according to claim 1, wherein the low-frequency threshold is about 1 MHz.

4. An electrical circuit according to claim 1, wherein the high-frequency threshold is about 10 MHz.

5. An electrical circuit according to claim 4, wherein the low frequency threshold is about 1 MHz.

6. An electrical circuit according to claim 1, further comprising a direct current isolator connected to the signal line and capable of supplying a direct current to a load.

7. A system comprising:

a plurality of electrical circuits according to claim 1, wherein each signal line of each of the plurality of electrical circuits is electrically connected to the signal line of every other electrical circuit.

8. A system according to claim 7, comprising three of the electrical circuits according to claim 1.

9. A system according to claim 8, wherein all of the electrical circuits are carried by a vehicle.

10. A system according to claim 9, wherein the vehicle is a military vehicle.

11. A system according to claim 9, wherein the vehicle is an emergency response vehicle.

12. A system according to claim 9, wherein at least one of the electrical circuits is capable of controlling the operation of lamp power on the vehicle.