T 2526/19 (Data-traffic-prioritisation mechanism for aircraft/THALES) 29-03-2022

1. Conducting oral proceedings by videoconference

1.1 Initially, the parties were summoned to in-person oral proceedings. Two weeks ahead of the scheduled oral proceedings before the board, the hearing was converted to VICO-based oral proceedings under Article 15a(1) RPBA.

1.2 In view of the pandemic developments and the resulting high incidences in Bavaria at the relevant time, the risk for an infection for all participants, including the board, was to be weighed up against the respondent's reservations as to holding VICO-based oral proceedings, the complexity of the case, and the suitability of the case for a hearing in this format.

1.3 The board, after having considered all these relevant criteria, came to the conclusion that a VICO-based hearing was indeed a suitable format for such proceedings under Article 15a(1) RPBA. Moreover, the compliance of Article 15a RPBA with the EPC has not been questioned by the Enlarged Board of Appeal in case G 1/21, whether or not a "general emergency" applies. Article 15a RPBA thus remains applicable, without any qualification, to these and future appeal proceedings.

2. Technical background

The patent concerns the wireless transfer of content such as weather information, voice and in-flight entertainment (IFE) between an aircraft 108 and a server 106 of a ground station while the aircraft is at a parking gate of the ground station (see Figure 1 of the patent reproduced below).

FORMULA/TABLE/GRAPHIC

A well-known system for this purpose is the so-called "Gatelink" approach. According to the patent, the implementation of this approach typically requires a modification of the airport facility. To address this, the patent proposes a mechanism to prioritise content transfer in accordance with at least the available link speed and the anticipated connection time between aircraft 108 and server 106. Via this prioritisation mechanism, the system of the invention is said to be able to adapt to the particularities of a given airport. By doing so, the proposed system purportedly operates with a minimal modification to the airport facility.

3. Main request: claim 1 - inventive step

Reasons 18 and 19 of the impugned decision are reviewed as follows in the light of the parties' arguments.

3.1 The parties contested neither the choice of E21 as the most promising starting point for the assessment of inventive step nor that E21 disclosed features (a) to (d). The board sees no reason to contest this either.

3.2 The respondent disputed that Figure 2 of E21 disclosed a traffic prioritisation mechanism as required by feature (e) because this figure showed merely to which one of radio towers 28, 30 and 32 the aircraft's client devices 46, 48, 50 and 52 and IFE server 23 were connected. The respondent argued that no traffic prioritisation took place in Figure 2 of E21 once these connections were established. By contrast, the respondent construed features (c) to (e) in the sense that the terrestrial communication link of claim 1 must already be established before the traffic prioritisation mechanism was provided, i.e. traffic was prioritised once the communication had started.

Even when adopting, arguendo, the respondent's interpretation of features (c) to (e) (although no temporal order can be derived as to the establishment of the terrestrial communication link and the application of the traffic prioritisation mechanism from the claim wording), the appellant correctly pointed out that paragraph [0021] and Figure 3 of E21 teach to establish, in a first step 74, an initial association and link by central terminal wireless LAN unit (TWLU) client 24 of aircraft 4 of Figure 2 of E21 and, in a second step 76, to search for all detectable access points. If only one access point is detected, a data transfer takes place, in a third step 78, in accordance with how a system manager prioritises the data from clients 46, 48, 50 and 52 of Figure 2 of E21. If multiple access points are detected, the system manager makes use of "a communication priority matrix" to provide for an optimised data transfer, as is explained in paragraph [0022] of E21. Either way, a traffic prioritisation mechanism is applied after the link between TWLU client 24 and one of radio towers 28, 30 and 32 was established.

3.3 As a result, paragraphs [0021] and [0022] together with Figure 3 of E21 indeed disclose feature (e).

3.4 The board acknowledges that E21 does not disclose feature (f). Instead, paragraph [0024] of E21 teaches creating the communication priority matrix by adopting the criteria of

(i) the number of available access points,

(ii) a detected signal strength and

(iii) how many clients are associated with each access point.

3.5 The board agrees with the appellant that the technical effect of feature (f) is, at best, that "an alternative implementation of the traffic prioritisation mechanism of E21 is provided".

The respondent's technical effect that a more efficient transfer of content would be provided cannot be credibly ascribed to feature (f): the use of the available link speed or the anticipated connection time to prioritise content transfer does not necessarily render this content transfer more efficient. Quite the opposite, it can be detrimental for the content transfer's efficiency if, for instance, the anticipated connection time turns out to be different than what was expected. Likewise, if the link speed changes due to interference and the content transfer prioritisation is changed accordingly, it could be that a particular content is never delivered to the aircraft. This may severely impact the transfer's efficiency, depending on which criteria are used to measure this efficiency.

3.6 Consequently, the board endorses the objective technical problem identified in Reasons 19.5.3 of the appealed decision and frames it as "how to provide for an alternative implementation of the traffic prioritisation mechanism of E21".

3.7 In contrast to the opposition division's positive assessment in Reasons 19.5.6 of the decision under appeal, in the board's view it would have been immediately apparent for the skilled person in the field of communication networks, based on their common general knowledge, to apply one of "available link speed" and "anticipated connection time" as an alternative for criteria (i) to (iii) mentioned in point 3.4 above. This can be analysed more in detail as follows:

3.7.1 Regarding the first alternative of feature (f), i.e. the criterion "available link speed", the board notes that this appears to be technically equivalent to criterion (ii) for all practical purposes. It would therefore have been obvious for the skilled person, when faced with the objective technical problem considered above, to arrive at the first one of the two alternatives mentioned in feature (f) by starting from E21 and drawing solely on their common general knowledge.

3.7.2 Concerning the second alternative of feature (f), the board will, for the sake of argument, adhere to the respondent's interpretation of the criterion "anticipated connection time" as an anticipated connection duration. In this respect, the term "airport schedules" of paragraph [0014] of E21, describing a prior-art communication system, can be seen as a rough estimate of such a duration. This is because an airport schedule will typically include an arrival and a departure time. Consequently, the skilled person would readily have considered the second alternative of feature (f) as an equally valid option based on the teaching of E21 itself.

3.8 In conclusion, the subject-matter of claim 1 of the main request does not involve an inventive step, contrary to Article 56 EPC.

4. First to third auxiliary requests: claim 1 - inventive step

4.1 Claim 1 of the first auxiliary request specifies in feature (g) that the traffic prioritisation mechanism of feature (e) operates in accordance with both criteria of feature (f), i.e. in accordance with the "available link speed" and the "anticipated connection time".

As regards inventive step, both criteria of feature (f) were known to the skilled person for the reasons set out in points 3.7.1 and 3.7.2 above. It would have been a simple routine-design measure for the skilled person to implement both criteria in the communication priority matrix of paragraph [0024] of E21. In particular, drawing upon their common general knowledge, the skilled person would have chosen either one of these criteria or a combination of those to implement the communication priority matrix of paragraph [0024] of E21, depending on how circumstances dictate.

4.2 Regarding claim 1 of the second auxiliary request, it is immediately apparent that the central TWLU client of paragraph [0021] of E21 must enable Aircraft/Ground Systems Communication device 70 shown in Figure 3 of E21 to support the type of link established by the access points, otherwise no communication would be possible. As a result, feature (h) is disclosed in paragraph [0021] of E21.

4.3 Claim 1 of the third auxiliary request is a mere juxtaposition of the features of claim 1 of the first and second auxiliary requests, which cannot lead to the acknowledgement of an inventive step either.

4.4 In conclusion, claim 1 of the auxiliary requests on file does not comply with Article 56 EPC either.