Invalidity dossier
US 5170392
Intermodulation compensation in a receiver
Current assignee: Motorola Solutions Inc
Added 9/23/2026, 5:43:21 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US 5,170,392 A
Title: Intermodulation compensation in a receiver
Patent number: US 5,170,392 A (application US07/642,102)
Inventor: Kenneth B. Riordan
Assignee: Motorola, Inc. (original assignee; current assignee listed as [Motorola Solutions Inc.](/litigations/by-defendant/Motorola%20Solutions%20Inc.))
Dates: Priority/filing date 1991-01-16; publication (grant) date 1992-12-08; anticipated expiration 2011-01-16. Legal status: Expired – Fee Related.
Purpose. In land-mobile/cellular base-stations, radio channel units (RCUs) share receive antennas through a Receiver Multicoupler Network (RMN). Sensitivity (noise figure) and intermodulation (IM) performance impose opposing design requirements: low front-end gain improves IM performance but costs sensitivity, and gain varies across RMN configurations and with frequency, temperature, and part-to-part tolerance. The patent addresses the resulting need to carry excess IM margin to guarantee sensitivity at the low end of the gain distribution.
Plain-language scope. As summarized in the supplied text, the receiver accepts at least one signal within a predetermined frequency band via at least one antenna having frequency-related characteristics, the antenna coupled to a modifying network having gain characteristic values related to the band's frequencies. The receiver stores those gain characteristic values, determines which stored value most nearly corresponds to the frequency of the input signal and the antenna's frequency-related characteristics, and provides at least one gain threshold value. The receiver compensates the input signal when the determined gain characteristic value exceeds that gain threshold. In the described embodiment (FIG. 4), a controller 205 decides when to insert or bypass an automatic intermodulation compensation (AIC) attenuator 400 ahead of receiver 200; memory 215 (RAM, with parameters initially in ROM) stores calibration values such as signal strength indicators, AGC parameters, and antenna path/frequency gain characteristic values. FIG. 5 depicts the compensation flow.
Source: https://patents.google.com/patent/US5170392/en
What the excerpt does not establish: the full claim language and count (the text is marked as an excerpt, with claim text omitted); the complete FIG. 5 steps; specific threshold values or calibration procedures; and the content of any foreign counterparts beyond their identification.
Generated 10/1/2026, 9:43:21 PM
Cases on file (0)
Specific litigation cases in our database that name US patent 5170392. The free-form analysis below may also discuss cases beyond this list.
No cases on file mention this patent. Upload a CSV or add a case manually in Admin → Manage litigation cases.
Litigation summary
Past and pending lawsuits — plaintiffs, defendants, jurisdictions, outcomes, and notable rulings.
Proceedings on file (0)
All PTAB activity →AIA trial proceedings (IPR / PGR / CBM) filed at the USPTO Patent Trial and Appeal Board against this patent. Sourced from the USPTO Open Data Portal and refreshed every six hours; each proceeding number deep-links to the PTAB E2E docket.
No PTAB proceedings on file. This patent has not been challenged via IPR, PGR, or CBM. The absence is itself a signal — well-asserted patents eventually attract IPRs. The LLM analysis below may surface filings the ODP feed hasn’t indexed yet.
PTAB challenges
AIA trial proceedings at the USPTO Patent Trial and Appeal Board — IPR, PGR, and CBM. Petitioners, judge panels, claim-level invalidation outcomes from Final Written Decisions, and Federal Circuit appeals. The single most important defensive datapoint after litigation history.
Assignment history
Inventors, original assignee, and the chain of ownership recorded with the USPTO — including the correspondent attorney who recorded each assignment, since shell-LLC chains often share one repeat-player attorney even when the entity names look unrelated. Surfaces NPE / patent-troll patterns: shell-entity transfers, known asserters in the chain, repeat correspondent fingerprints, pre-litigation assignments, and bankruptcy fire-sales.
Prior art
Earlier patents, publications, and products that may anticipate or render the claims unpatentable.
Obviousness
Combinations of prior art that suggest the claimed invention would have been obvious under 35 U.S.C. § 103.
Extensions
Patent term adjustments, term extensions, continuations, divisionals, family members, and expiration dates.
Derivative works
Defensive disclosure: derivative variations of each claim designed to render future incremental improvements obvious or non-novel.