# US 2018/0027705 A1 · Methods, devices, and systems for filtering electromagnetic interference > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0027705 A1 - Document ID: US20180027705A1 - Status: Published application - Kind: A1 - Application number: 15/713,447 - Filed: 2017-09-22 - Published: 2018-01-25 - Earliest claimed: 2010-02-03 - Assignees: Djm Electronics, Inc. - Applicants: Djm Electronics, Inc. - Inventors: Stephen D. McNally - Web page: https://patentgrep.com/patent/US20180027705A1 ## CPC - H05K 9/002: {with localised screening} - H03H 1/0007: {of radio frequency interference filters} - H05K 9/0066: {Constructional details of transient suppressor} - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) ## Abstract Provided herein are methods, devices, and systems that relate to electromagnetic interference (EMI) filters that, in certain embodiments, comprise: (a) a housing comprising a substantially enclosed first compartment and a substantially enclosed second compartment; (b) a first circuit card located in the first compartment of the housing that converts a signal transmitted on a conductive based medium to a signal transmitted on a non-conductive based medium; (c) a second circuit card located in the second compartment of the housing that converts a signal transmitted on a non-conductive based medium to a signal transmitted on a conductive based medium; (d) at least one non-conductive based medium that transmits a signal from the first circuit card to the second circuit card; and (e) at least one waveguide through which the non-conductive based medium passes from the first compartment to the second compartment. ## Claims ### Claim 1 An electromagnetic interference (EMI) filter comprising: (a) a housing comprising a substantially enclosed first compartment and a substantially enclosed second compartment; (b) a first circuit card located in the first compartment of the housing that converts a signal transmitted on a conductive based medium to a signal transmitted on a non-conductive based medium; (c) a second circuit card located in the second compartment of the housing that converts a signal transmitted on a non-conductive based medium to an Ethernet signal that is compliant with the IEEE 802.3 family of standards; (d) at least one non-conductive based medium that transmits a signal from the first circuit card to the second circuit card; and (e) at least one waveguide through which the non-conductive based medium passes from the first compartment to the second compartment; the filter providing a radiated electromagnetic emission amplitude (dBμV/m) versus frequency (Hz) graph having a largest peak within a frequency range of about 30 MHz to about 1 GHz that is equal to or less than about 44 dBμV/m when measured at a distance of about 3 meters from the filter. ### Claim 2 (depends on 1) The filter of claim 1 where the Ethernet signal is compliant with the IEEE 802.3u standard (100BASE-TX) and that provides a radiated electromagnetic emission amplitude (dBμV/m) versus frequency (Hz) graph having a largest peak within the frequency range of about 30 MHz to about 1 GHz that is equal to or less than about 40 dBμV/m when measured at a distance of about 3 meters from the filter. ### Claim 3 (depends on 1) The first or second compartment of claim 1 that incorporates at least one solid or braided shield to separate all or a portion of at least one circuit card from a conductor based medium. ### Claim 4 (depends on 1) The conductive based medium of claim 1 that that passes through one or more ferrites having an initial permeability that is equal to or less than about 100. ### Claim 5 (depends on 1) The conductive based medium of claim 1 that passes through at least one additional electromagnetic interference filter before exiting the compartment. ### Claim 6 An electromagnetic interference (EMI) filter comprising: (a) a housing comprising a substantially enclosed first compartment and a substantially enclosed second compartment; (b) a first circuit card that converts a signal transmitted on a conductive based medium to a signal transmitted on a non-conductive based medium and located in the first compartment of the housing; (c) a second circuit card located in the second compartment of the housing that converts a signal transmitted on a non-conductive based medium to a signal transmitted on a conductive based medium; (d) at least one non-conductive based medium that transmits a signal from the first circuit card to the second circuit card; and (e) at least one waveguide through which the non-conductive based medium passes from the first compartment to the second compartment; wherein the filter utilizes, passes, or provides a digital signal compliant with a specification that provides for integrated power. ### Claim 7 (depends on 6) The housing of claim 6 that has a volume that is equal to or less than about 150 cubic inches. ### Claim 8 (depends on 6) The signal of claim 6 that is a network or peer-to-peer protocol. ### Claim 9 (depends on 6) The signal of claim 6 that is a communication protocol between a host and peripheral device. ### Claim 10 An electromagnetic interference (EMI) filter comprising: (a) a housing comprising a substantially enclosed first compartment and a substantially enclosed second compartment; (b) a first circuit card located in the first compartment of the housing that converts a signal transmitted on a conductive based medium to a signal transmitted on a non-conductive based medium; (c) a second circuit card located in the second compartment of the housing that converts a signal transmitted on a non-conductive based medium to a signal transmitted on a conductive based medium that conveys data at a rate faster than one gigabit per second; (d) at least one non-conductive based medium connector that transmits a signal from the first circuit card to the second circuit card; and (e) at least one waveguide through which the non-conductive based medium connector passes from the first compartment to the second compartment. ### Claim 11 (depends on 10) The signal of claim 10 that is a network or peer-to-peer protocol. ### Claim 12 (depends on 10) The signal of claim 10 that is a communication protocol between a host and peripheral device. ### Claim 13 An electromagnetic interference (EMI) filter comprising: (a) a housing comprising a substantially enclosed first compartment and a substantially enclosed second compartment; (b) a first circuit card located in the first compartment of the housing that converts a signal transmitted on a conductive based medium to a signal transmitted on a non-conductive based medium; (c) a second circuit card located in the second compartment of the housing that converts a signal transmitted on a non-conductive based medium to a signal transmitted on a conductive based medium; (d) at least one non-conductive based medium that transmits a signal from the first circuit card to the second circuit card; and (e) at least one waveguide through which the non-conductive based medium passes from the first compartment to the second compartment; that is characterized by one or more of the following: (i) the filter being designed to meet or exceed at least a portion of a military specification or standard; (ii) the housing being designed to meet or exceed at least a portion of a military specification or standard; (iii) at least one of the conductive based media being embodied in a connector that is designed to meet or exceed at least a portion of a military specification or standard; (iv) at least one of the compartments being designed to meet or exceed at least a portion of a military specification or standard; or (v) at least one of the circuit cards being designed to meet or exceed at least a portion of a military specification or standard. ### Claim 14 (depends on 13) The filter of claim 13 that complies with at least one of the following standards or specifications MIL-STD-810, MIL-STD-461, MIL-DTL-26482, TEMPEST, DEF STAN 00-35, AECTP-100, or IP50. ### Claim 15 (depends on 13) The first or second compartment of claim 13 that has been completely or partially filled with a non-conductive solid compound, a ferrite loaded compound or a conformal coating. ### Claim 16 (depends on 13) The housing of claim 13 that further comprises an antichafe material. ### Claim 17 (depends on 1, 6) The filter of claims 1, 6, and 10 that further comprises an AC/DC power transformer that is located in at least the first or second compartments. ### Claim 18 (depends on 6, 10) The filter of claims 6 and 10 that further comprises a power source that is supplied by the same cable transmitting a communication signal. ### Claim 19 (depends on 13) The filter of claim 13 that further comprises a power supply that is a battery or fuel cell. ### Claim 20 (depends on 13) The housing of claim 13 that that has a volume that is equal to or less than about 40 cubic inches. ### Claim 21 (depends on 1, 6, 10) The waveguide of claim 1, 6, 10, or 13 that has an inner diameter that is equal to or less than about 1 inch.