Electrical Communications Searching Best Practices

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Electrical Communications is broadly defined by the United States Patent and Trademark Office as the handling of information or intelligence and is not restricted to the conveying of the information or intelligence between geographically spaced points. By this definition, inventions in electrical communications can range from an invention as simple as a blinking LED on a CD-ROM drive to a complex cellular telephone network. Currently, most electrical communication inventions include the transmission and reception of information between two or more points. This information is transferred via digital or analog signals over wired or wireless paths. In many cases, one or more of these paths is combined to form a network for communicating information to a larger area.

Obstacles Facing the Searcher

Electrical Communications searching is often made more difficult by the complex nature of the terminology used in the field. Due to varying levels of detail present in patent drawings in this field, full-text searching using a variety of keywords is typically the most reliable way to find specific features. However, detailed knowledge of the particular technology is necessary in order to incorporate appropriate synonyms in the search. Further complicating this task is the introduction of newer terminology that implicitly includes multiple terms (e.g. "bearer" in radio networks vs. the whole set of "base station," "radio channel," "multiple access method," etc). This can make things difficult for the searcher when he or she does not have a detailed familiarity with the art.

Standards play a large role in defining how various protocols and electrical communications systems operate. Standards encourage a uniform design for purposes of interoperability and cost among other reasons. It is often cumbersome to search standards as it usually consists of reviewing white papers and multiple revision addendums to the standards. However, at some point during a search, it is recommended to identify and attempt to find any potential standards that may be applicable to the subject matter being searched. Electrical communications searches almost always have some type of standards searching incorporated into the search. Knowledge of these standards can go a long way in helping to expedite searches in this field. Organizations such as the Institute of Electrical and Electronics Engineers (IEEE) approve specifications such as 802.x that provide in-depth detail about those protocols.

Searching Patent Documents

Patent searching in the art of Electrical Communications is normally done with a combination of keyword text searching and image-based searching. Search tools that are able to perform both of these types of searches are often preferred by searchers in this field.

Searching Non-Patent Literature

Fortunately for searchers in this field, Electrical Communications and related fields such as Computer and Information Sciences and Electrical Engineering have a large number of non-patent literature resources available.

Google, and particularly Google Scholar, is a source that can be used for finding articles in very new technologies. Google Scholar accesses multiple sources, is able to retrieve scientific articles and often can be used as a source from which to retrieve PDF (Portable Document Format) versions of scientific publications.

Some additional recommended resources include: IEEE Explore, ACM, Knovel, and netLibrary which has hundreds of technical books. Furthermore, NTIS, Compendex, Ei Backfile, INSPEC, SoftBase, Dissertation Abstracts and the Gale Groups databases can be accessed from a number of sources such as Engineering Village, Questel (Qweb and QPAT), and Dialog.

IP.com prior art database is a place where hundreds of corporations publish technical disclosures including IBM, Microsoft, Motorola, Siemens, and Sony. Cambridge Scientific Abstracts (CSA) Illumina includes Electronics and Communications, Computer and Information Systems, and Communication Abstracts that covers major areas including circuits, electronics, and telecommunication systems.

Some organizations that define standards for their respective industries include:

  • The Telecommunication Standardization Sector (ITU-T) of the International Telecommunication Union is a reference for standards in the telecommunications industry that often help searchers in finding specific features, (e.g. particular frequencies, data rates, etc).
  • The USB (Universal Serial Bus) specification is full of preferred embodiments due to the fact that USB continues to evolve and requires continual tweaking as device technology advances. This resource is especially helpful when searching for information concerning serial multiple access networks with isochronous transfer support.
  • Alliance for Telecommunications Industry Solutions homepage. Its standardization activities for wireless and wireline networks include interconnection standards, number portability, improved data transmission, Internet telephony, toll-free access, telecom fraud, and order and billing issues, among others.

Specific Search Strategies

These search strategies are examples of specific best practices that can be applied during the course of a search in the area of Electrical Communications. These are steps to be taken in addition to accepted general search practices that apply to all searches. For a more general progression of search steps, please see the [General_Searching_Best_Practices|General Searching] article.

  • In the field of Electrical Communications especially, features not suspected to be novel can often be found in all-encompassing patents or standards documents. Keeping a copy of these documents handy as they are found will help in future searches on similar subject matter. Having these types of patents that will apply to more than one search will also help a searcher distinguish the novel features of an invention from what is well known in that particular art. As an example of an all-encompassing patent, US 6,693,909 B1 (Mo et al), covers several Quality of Service (QoS) concepts that are often applicable to electrical communications searches having a QoS component. The ‘909 patent discloses a switching network supporting IP and MPLS (the latter being where it’s at in the telecom world these days), run over diverse link types (col. 3-col. 4), Ethernet, frame relay, SONET, etc. All types of network technologies are disclosed. Furthermore, (col. 6), it discloses routing protocols as well as NAT and obfuscation techniques. Mo et al. also discloses “Internet protocol transport nodes” which accomplish many and sometimes all the functions of a switch.
  • In the editor’s experience, searching non-patent literature using non-patent sources identified above is often a good first step before searching any patent sources. Especially with newer technologies, journals such as IEEE and ACM as well as the IP.com prior art database often help in further understanding the technology as well as identifying potential inventors and assignees (owners) of interest. The level of activity in a technology can also be gauged based on the number of published journal articles related to the technology.
  • Review closely related patents for common assignees and inventors. Electrical Communications is an area of technology where a handful of big players are doing a large amount of research and receiving the lion’s share of patents. Keep track of the major players in the field and keep them in mind when searching.
  • Extend the search to any applicable standards. Many electrical communications inventions are anticipated or rendered obvious by standards and proprietary but published extensions to standards. A good example is “USB On-The-Go”, a technology that enables communication among USB devices without management by a host PC; anticipating serial bus interconnects in embedded devices.

Key Classification Areas

The following US, IPC, and Japanese classes are central to searching in the field of Computer and Information sciences. A phone conversation with a USPTO Examiner is recommended after identifying some initial classes and subclasses. Due to technologies becoming increasingly multidisciplinary, this is not an exhaustive list and other classes may apply.

Class Description
181 Acoustics
340 Electrical Communications
342 Directive Radio Wave Systems and Devices (e.g., Radar, Radio Navigation)
343 Radio Wave Antennas
367 Electrical Communications: Acoustic Wave Systems and Devices
370 Multiplex Communications
375 Pulse or Digital Communications
379 Telephonic Communications
381 Electrical Audio Signal Processing Systems and Devices
398 Optical Communications
455 Telecommunication
... See links in the header of this table for full class definitions

IPC on WIPO / ECLA in espacenet
Class Description
G01S Radio Direction-Finding; Radio Navigation; Determining Distance or Velocity by Use of Radio Waves; Locating or Presence-Detecting By Use of the Reflection or Reradiation of Radio Waves; Analogous Arrangements Using Other Waves
G08B Signaling or Calling Systems
H04B Transmission
H04H Broadcast Communication
H04J Multiplex Communication
H04L Transmission of Digital Information
H04M Telephonic Communication
... See links in the header of this table for full class definitions

Japanese F-Terms
Class Description
5B035 Record Carriers for Digital Markings
5C086 Alarm Apparatuses Responsive to Abnormal Conditions
5H180 Traffic Control Systems
5J104 Ciphering Device, Decoding Device and Privacy Communication
5J100 Control of Amplification and Gain Control
... See links in the header of this table for full class definitions


For further reading, searchers should reference the corresponding best practices articles covering electrical engineering and computer and information sciences and physical sciences. Due to some overlap in the fields, the best practices and sources disclosed in those articles may also be applicable to Electrical Communications searches.


  1. "Class Definition for Class 340." USPTO website, http://www.uspto.gov/web/patents/classification/uspc340/defs340.htm. Accessed on March 25, 2009.

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