Analysis of essential patent portfolios via bibliometric mapping: an illustration of leading firms in the 4G era

Abstract

This study aims to analyse the essential patent portfolios of individual firms via bibliometric mapping. Based on the maps drawn via this method, important clusters of each company are analysed and two interpretations are made. As an illustration, the mobile phone industry is selected because standardisation is highly important for firms in this industry. Among others, long-term evolution (LTE) of the 4G era is chosen as a standard and Qualcomm, Nokia, Ericsson, and NTT DOCOMO are included as leading firms. As a result, firm-wise LTE essential patent portfolios were visualised. Based on the information given in these maps, two important clusters (i.e. the clusters composed of frequently emerging words and their periphery and the clusters including particularly noticeable terms) were analysed. In addition, two interpretations were made as follows. First, specialised and expandable technological clusters for each company (14 specialised/expandable clusters for Qualcomm, 8 for Nokia, 11 for Ericsson, and 10 for NTT DOCOMO) were identified. Second, appropriate cooperative strategies were devised according to the ownership patterns of technologies as follows. To begin with, if the technologies were owned by one company (e.g. multi-carriers, duplex channel, error correction), a non-cooperative strategy, such as non-exclusive licensing, was advised. Next, when the technology was owned by two companies (i.e. OFDM (orthogonal frequency-division multiplexing)), a cooperative strategy, such as cross-licensing, was recommended. Finally, if the technologies were owned by multiple companies (i.e. MIMO (multi-input and multi-output) and data transmission), then a cooperative strategy, such as a patent pool, was proposed.

Keywords:

• standardisation
• essential patents
• bibliometric mapping
• 4G
• LTE

Disclosure statement

No potential conflict of interest was reported by the author.

Funding

This research was supported by the Sookmyung Women's University Research Grants [number 1-1403-0226].

Notes on contributors

Yoo-Jin Han is currently associate professor in the Department of Entrepreneurship, the School of Global Service, Sookmyung Women's University. She holds B.Sc. in Industrial Management from the Korea Advanced Institute of Science & Technology (KAIST) and MBA in International Business and Ph.D. in the Management of Technology from Seoul National University. Her research interests lie in technology management, patent analysis, bibliometric analysis and entrepreneurship, and relevant articles were published in various journals such as World Patent Information, Economics of Innovation and New Technology and Journal of Informetrics.

Notes

1. Patents needed to produce standards-compliant goods. The relationship between standardisation and essential patents is described in Section 2.2.

2. The acronym for the European Telecommunications Standards Institute.

3. Subjects that own patents for licensing or litigation and not for commercialisation (e.g. Interdigital).

4. Given that firms cannot demand additional rights once patent documents have been finalised, they tend to take sufficient time to consider which elements should be incorporated into these documents.

5. The concept similar to essential patents, that is, seminal patents, was adopted for the analysis.

6. Strictly speaking, LTE corresponds to the category of 3.9 standards because it does not meet the requirements of International Mobile Telecommunications (IMT)-Advanced, which is the 4G technology specification proposed by the International Telecommunication Union (ITU). However, this standard can be adopted, given that major mobile phone companies incorporate LTE into the 4G standards category for their technological strategy formulation (Verizon 2012; GSMA 2014).

7. The acronym for Worldwide Interoperability for Microwave Access. Technologies are implemented similarly to those in LTE because WiMax is also based on orthogonal frequency-division multiplexing (OFDM) and multi-input and multi-output (MIMO) technologies (Verizon 2012). However, WiMax cannot cover various frequencies and can only enable roaming in limited countries. Although it was commercialised ahead of the LTE in 2007, few major telecommunications companies participate in its standardisation (Actiontec 2010). Therefore, its market growth rate has stagnated compared with that of the LTE.

8. The numbers of LTE standards and essential patents owned by each company at the end of 2013 are shown in Table 3.

9. For example, International Standards Organization (ISO), ITU, European Technology Institute of Electrical and Electronic Engineers (IEEE), and World Wide Web Consortium (W3C).

10. Established in 1988, it has played a crucial role in the standardisation of telecommunication-related equipment and devices, electronic parts, and protocols in the European region. It currently has 750 members from 63 countries.

11. Fair, reasonable, and non-discriminatory. The ETSI recommends companies to license their technologies based on this principle so as to avoid unfair competition among industry players.

12. (i) As the number of NTT-DOCOMO users, which developed the first W-CDMA technology, did not increase significantly, the company was unable to decisively invest in the development of the next-generation technology (UMTS Forum 2006); (ii) because the development of the CDMA 2000 technology allowed the provision of services similar to the W-CDMA-based ones, handset manufacturers and telephone companies adopted the CDMA 2000 ahead of the W-CDMA (Saugstrup and Henten 2006; UMTS Forum 2006); and (iii) numerous telecommunication service providers hesitated to invest in the 3G technology because they anticipated the rise of the 4G era (UMTS Forum 2006).

13. Unlike cross-licensing, a patent pool was formed in 2012 (Via Licensing 2012). However, the number of participants is very limited, not including most of the leading firms (except NTT DOCOMO) selected in this research.

14. h = 0.125 in the VOSviewer by default.

15. The number of words included and the number of words displayed in the density view differ. If a researcher wishes to interpret data based on less frequently interconnected words, the VOS viewer offers a function that includes words in the overlapping regions.

16. A database of information on European standards and relevant patents.

17. The year when firms started to declare their LTE essential patents to ETSI.

18. The most recent year when data can be obtained.

19. (1) If one patent is related to several standards, it is counted once. (2) If the same patent is applied to multiple countries, it is also counted once.

20. A network should be designed according to ISO/IEC (International Electrotechnical Commission) standard 7498-1, which consists of seven layers, namely, physical, data link, network, transport, session, presentation, and application layers (ISO/IEC 1994). These layers are also bifurcated; the first three correspond to the media layer, which controls the physical delivery of a message over the network. The remaining layers belong to the host layer, which shares accurate data on devices.

21. Mechanical/electrical specifications of parts and devices, the characteristics of each device, and the condition for the connection of each device (Rumney 2013).

22. The number of words is determined by researchers in consideration of visibility and interpretability (Van Eck and Waltman 2010; Curran and Leker 2011).

23. Shown in the boxes in Figure 1. Interpretation is followed in the order of the numbers marked in each box.

24. A one-to-one transmission between a transmitter and a receiver that is easy to implement (Horak 2007). A unicast enables dialogue-based operations and provides multiple bit-rate streaming capability; however, it places considerable load on a system because it must duplicate the same information according to the number of users.

25. An operation that requests permission to send signals from a mobile station to a base station because a multitude of mobile stations compete for a limited number of radio link resources (Horak 2007).

26. The most appropriate request alternative among multiple ones that are sent from a mobile station to a base station (Horak 2007).

27. A signal that does not contain useful information and is used only to supervise, control, equalise, synchronise, and reference sub-carriers (Bahai, Saltzberg, and Ergen 2004).

28. A point-to-point system that transmits and receives information between two connected devices (Horak 2007).

29. Any part of a computer that can be controlled by an operating system (Horak 2007).

30. A channel that enables simultaneous information transmission in both directions (Horak 2007).

31. The receipt and downloading of data to a mobile device from a remote server/base station (Horak 2007).

32. A spectrum-spreading technique used for Bluetooth, which is a standard technology that enables data exchange over a short distance (Horak 2007).

33. Arrangement of the functional units of a system for random access (Horak 2007).

34. A technique that converts part of an output into an input.

35. Coordination of events to activate various units in one system or in two devices simultaneously.

36. The sending and uploading of data from a mobile device to a remote server/base station (Horak 2007).

37. Uplink.

38. Acknowledgement/Negative acknowledgement. A message used to notify to the transmitter whether the data have been successfully/unsuccessfully transmitted to the receiver (Horak 2007).

39. Forward error correction (Sesia, Toufik, and Baker 2009).

40. A scheme that enables a receiving terminal to request the retransmission of erroneous packets (Horak 2007; Sesia, Toufik, and Baker 2009).

41. A scheme that combines the ARQ and the FEC to correct errors caused by channel quality (Sesia, Toufik, and Baker 2009).

42. A signal that indicates whether a data rate is suitable for downlink transmissions (Sesia, Toufik, and Baker 2009).

43. Physical uplink control channel: an uplink physical channel that carries uplink control information including channel quality indicators (CQI), HARQ, ACK/NACK, and uplink scheduling requests (Sesia, Toufik, and Baker 2009).

44. Shown in the boxes in Figure 2. Interpretation is followed in the order of the numbers marked in each box.

45. A technique that enables numerous users to share a spectrum efficiently (Horak 2007).

46. A technique that installs multiple antennas on a transmitter (Sesia, Toufik, and Baker 2009).

47. A program that determines the order of the processes among various types of hardware (Bahai, Saltzberg, and Ergen 2004).

48. A preliminary signal used to synchronise transmission timing between or among two or more systems (Horak 2007). Without this signal, all of the information may be falsely transmitted when the data packet encounters an error (Bahai, Saltzberg, and Ergen 2004).

49. The acronym for user equipment, which refers to any device used by end users (Sesia, Toufik, and Baker 2009).

50. GSM/enhanced data rates for GSM evolution: a GSM-based technique that generates a high maximum data transmission rate of 473.6 kbps (Horak 2007).

51. High-speed downlink shared channel: an enhanced 3G communication protocol that accelerates downlink transmission by adding a new transport channel to the high-speed downlink packet access, which is an enhanced 3G standard (Rumney 2013).

52. Transmission time interval: the minimum duration of data transfer from the data-link layer to the physical layer (Sesia, Toufik, and Baker 2009).

53. A signal that permits uplink/downlink transmission (Sesia, Toufik, and Baker 2009).

54. Protocol data unit: a transmission unit in the same layer (Sesia, Toufik, and Baker 2009).

55. Enhanced general packet radio service: an improved form of GSM network that applies the EDGE technique to the GPRS, that is, a 2.5 G standard for data transmission (Horak 2007).

56. Power headroom report: a method that indicates how much power is currently used and how much transmission power remains (Sesia, Toufik, and Baker 2009).

57. A technique that amplifies power in a wireless communication system (Horak 2007).

58. Shown in the boxes in Figure 3. Interpretation is followed in the order of the numbers marked in each box.

59. An electronic switching system that enables circuit (a line for telephone communication) exchange, mobility, and GSM communication (Horak 2007).

60. The technique that maintains the connections among base stations is interchanged with the word ‘handover’ (Sesia, Toufik, and Baker 2009). Hard handoff refers to a method that reconnects two base stations after disregarding the transmission from the previous station. Soft handoff is a method that connects two base stations simultaneously (Horak 2007).

61. A network in which the same signal is transmitted simultaneously over the same frequency channel (Sesia, Toufik, and Baker 2009).

62. A prefix that denotes a factor of 10⁻¹⁵. This word refers to a micro mobile station for homes and small offices in the mobile communications sector (Horak 2007).

63. The acronym for the multimedia broadcast multicast service that refers to point-to-multipoint interface specifications in broadcast and multicast services for efficient delivery (Sesia, Toufik, and Baker 2009).

64. A technology that manages data delivery using circuit-switched networks, such as telecommunications networks, in which a dedicated channel is established between two nodes prior to communication (Horak 2007).

65. TR 36.806, TR 36.815, TR 86..871, TR 36.912, and TR 36.913.