SE1651312A1 - Improved ability to interact with passive beacon receiver devices in a short-range wireless beacon communication system - Google Patents

Abstract

A beacon communication system has a plurality of beacon transmitter devices (BTD, BTD, BTD, 700; 900), each beacon transmitter device comprising a controller (710; 910) and a short-range wireless beacon transmitter (732; 932). The controller causes a first transmission (SI 2) of a short-range wireless beacon signal (BA1) by the beacon transmitter, the beacon signal identifying a beacon region, then waits during a beacon delay time period (BDTP), and causes a second transmission (S32) of the short-range wireless beacon signal (BA1) by the beacon transmitter. The beacon delay time period (BDTP) is sufficiently long to allow a short-range wireless beacon receiver device (PI), when being in a passive mode, being in range of the beacon region and having received the first transmission of the beacon signal, to receive and react (S34) on the second transmission of the beacon signal. The first transmission of the short-range wireless beacon signal (BA-BA), the waiting during the beacon delay time period (BDTP), and the second transmission of the short-range wireless beacon signal occur essentially concurrently at the respective beacon transmitter devices. The beacon communication system further has an external device (SS, SP), and each beacon transmitter device (BTD, BTD, BTD, 700; 900) has a communication interface (734; 934) for data communication. The external device periodically sends a beacon transmission synchronization signal (BTSS) to the beacon transmitter devices (BTD, BTD, BTD, 700; 900). The controller (710; 910) of each beacon transmitter device (BTD, BTD, BTD, 700; 900) receives a first beacon transmission synchronization signal (510) from the external device (SS, SP) via the communication interface, causes the first transmission of the short-range wireless beacon signal (BA-BA) by the beacon transmitter (732; 932), receives a second beacon transmission synchronization signal (530) from the external device (SS, SP) via the communication interface, and causes the second transmission of the short-range wireless beacon signal by the beacon transmitter (732; 932).To be published with Fig 5 A

Description

CF 030~Div 1 IMPROVED ABILITY TO INTERACT WITH PASSIVE BEACON RECEIVERDEVICES IN A SHORT-RANGE WIRELESS BEACON COMMUNICATIONSYSTEM TECHNICAL FIELD The present invention generally relates to the field of beacon communicationand short-range wireless beacon transmitter devices. More specifically, the inventionrelates to a short-range wireless beacon transmitter device, beacon communicationsystem and associated method with improved ability to detect passive beacon receiver devices.

BACKGROUND Short-range wireless beacon transmitter devices are used at various sites, suchas shops, restaurants, cultural venues and sport arenas, to attract attention from nearbyusers of mobile communication devices such as mobile terrninals like smartphones ortablets. The abbreviated notion mobile devices will be used herein when referring tosuch mobile communication devices.

For instance, the iBeacon technology from Apple allows for mobile devices tounderstand their location on a micro-local scale, and also allows delivery of hyper-contextual content to the users of mobile devices based on their current location. TheiBeacon technology is based on the Bluetooth Low Energy (BLE) standard, and moreparticularly on Generic Access Profile (GAP) advertising packets. There are severalother kinds of short-range wireless beacon technologies, for instance AltBeacon,URIBeacon and Eddystone, which are also based on BLE and GAP.

A basic short-range wireless beacon communication system is shown in Fig1A. A beacon transmitter device Bl repeatedly broadcasts a short-range wireless beaconsignal (also known as a beacon advertisement signal) BA1 in a 31-byte GAP BLEpacket. The beacon signal BA1 contains a 128-bit universally unique identifier, UUID.The beacon signal BA1 may also include a 16-bit major portion and a 16-bit minorportion. The beacon signal BA1 identifies a beacon region associated with the beacontransmitter device B1. Whereas, as is commonly known, a geographical region is an areadefined by a circle of a specified radius around a known point on the Earth”s surface, abeacon region is in contrast an area defined by a mobile device°s proximity to one or more beacon transmitter devices.

CF 030~Div 1 In some implementations, the beacon region is represented by the UUID, themajor portion and the minor portion in the beacon signal BA1_ In other implementations,the beacon region is represented by the UUID and the major or minor portion in thebeacon signal BA1. In still other implementations, the beacon region is represented bythe UUID alone.

In Fig 1A, a second beacon transmitter device B; also repeatedly broadcasts ashort-range wireless beacon signal BA; for the same beacon region as the first beacontransmitter device B1.

A conventional beacon transmitter device is typically static in the sense that itis perrnanently placed at a stationary location at a site for which beacon-triggeredservices are to be provided. Mobile devices nearby may receive the short-range wirelessbeacon signal BA1 if they are within range of the beacon transmitter device B1.

To this end, each mobile device is provided with an application program, app,which is configured to detect and react on short-range wireless beacon signals, such asbeacon signal BA1, with support from the underlying operating system. In one knownbeacon technology, the apps in mobile devices can detect and react on beacons in twoways, monitoring and ranging. Monitoring enables the app to detect movement in andout of the beacon region (i.e., whether the mobile device is within or outside of therange of any of the beacon transmitter devices with which the beacon region isassociated). Hence, monitoring allows the app to scan for beacon regions. Ranging ismore granular and provides a list of beacon transmitter devices in range, together withtheir respective received signal strength, which may be used to estimate a distance toeach of them. Hence, ranging allows the app to detect and react on individual beacontransmitter devices in a beacon region.

These apps may be handled by the operating system of the mobile device indifferent modes. The most prominent mode is the active mode, in which the appexecutes in the foreground and is typically capable of interacting with the user of themobile device and also to communicate with an extemal device such as a server via theshort-range wireless beacon interface and/or another communication interface. Asregards short-range wireless beacon communication, ranging only works when the appis in active mode.

In Fig 1A, two mobile devices in the active mode are shown as A1 and A2.When, for instance, mobile device A1 receives the beacon signal BA1, the app in themobile device A1 may detect that it has entered the beacon region from the UUID (and the maj or/minor as the case may be) contained in the beacon signal BA1, and react as CF 030~Div l appropriate in some way which is beneficial to the user and/or the host of the beacontransmitter device B1 and which often involves interaction between the app in themobile device A1 and a service provider SP over a communication network NW. Asystem server SS may also be included in some implementations.

Examples of such benef1cial use include, without limitation, deterrnining acurrent approximate position of the mobile device A1 by retrieving a predef1ned positionof the beacon transmitter device B1 from the service provider SP or by cross referencewith local lookup data, or retrieving a content from the service provider SP.

A mobile device where the app is in active mode is referred to as an activemobile device in this document. An active mobile device A1, A2 may receive and reactto additional transmissions of the beacon signal BA1 from the beacon transmitter deviceB1; this may be useful for instance if the content associated with the host of the beacontransmitter device B1 is updated or changed.

Furthermore, an active mobile device may receive and react to beacon signalsfrom other beacon transmitter devices nearby, such as beacon transmitter device B; inFig lA, provided of course that they are within range of the respective beacon trans-mitter device (see mobile device A2 with respect to beacon transmitter device B; in FiglA), or move closer to it (mobile device A1 and beacon transmitter device Bg). This isso irrespective of whether the different beacon transmitter devices B1 and B; advertisethe same beacon region (i.e. contain the same UUID and maj or/minor in the respectivebeacon signals BA1 and BAg, like in Fig lA), or different beacon regions (provided thatthe app is configured to monitor for such different beacon regions). It is to be noticedthat the same beacon region (e. g. same UUID) is very often used for different beacontransmitter devices hosted by the same host, such as within the same superrnarket,arena, fastfood restaurant, etc.

The operating system of the mobile devices may also handle apps in a passivemode. A purpose of the passive mode is power preservation, since the mobile devicesare typically powered by batteries and since it is a general technical ambition tomaximize the operational time of a mobile device between successive charging sessions.In the passive mode, the app executes in the background or is only installed on themobile device. Unlike ranging which only works when the app is in active mode,monitoring works when the app is in active mode as well as when the app is in passive mode.

CF 030~Div l Transitions between active mode and passive mode may be based on userinteraction, user preference settings in the app or the operating system, or program logicin the app or the operating system.

A mobile device where the app is in passive mode is referred to as a passivemobile device in this document. In the passive mode, the app typically cannot interactwith the user via the user interface, nor communicate with a server or another device -except for the following. Just like active mobile devices, a nearby passive mobile device(such as P1 in Fig lA) may monitor for a beacon region and hence receive a short-rangewireless beacon signal (such as BA1 or BAg) if it is within range of the beacon trans-mitter device in question (e. g. B1 or Bg). However, unlike active mobile devices, after ashort beacon scanning period in the monitoring, during which the beacon transmitterdevice B1 or Bg is discoverable and also communication with a server or another deviceis possible, and unless it switches to active mode, the passive mobile device P1 will gbe able to react to additional beacon signals for the same beacon region from the beacontransmitter device B1 or Bg.

Instead, after the short beacon scanning period (which typically lasts for someseconds, such as about l0 seconds), the passive mobile device P1 will be ““ignorant” or“deaf to”, i.e. not react on, additional beacon signals for the same beacon region for aslong as it stays in passive mode and continues to detect such beacon signals, forinstance because it remains within range of the beacon transmitter device B1 (or Bg) andcontinues to detect its beacon signal. Only once the passive mobile device P1 has notreceived the beacon signal BA1 or BAg, or any other beacon communication whichadvertises the same beacon region, for a certain time, such as l-l5 minutes, the passivemobile device P1 will again be reactive to the beacon signal BA1 or BAg, or any otherbeacon communication which advertises the same beacon region.

An example situation to illustrate the above is given as a schematic timelinediagram in Fig lB. The beacon transmitter device (BTD) B1 transmits the beacon signalBA1 at a certain periodicity, with a short time At between each transmission of thebeacon signal BA1 at steps S12, S22, S24 and S32. The time At between successivetransmissions of the beacon signal BA1 is typically in the order of l second. A beaconmarket analysis performed by the present applicant has found that the beacontransmission periodicity is at about l Hz or higher for a number of beacon transmitterdevices from different manufacturers, which means that the time At between successive transmissions of the beacon signal is l second or less.

CF 030~Div 1 During the short beacon scanning period S10 of the monitoring, the passivemobile device P1 in Fig 1B will therefore be able to detect and react on the firsttransmission S12 of the beacon signal BA1. The reaction may, for instance, involvereporting to an extemal device such as a server SS that the beacon region identified bythe beacon signal BA1 has been entered, see steps S14 and S16. Following this, thepassive mobile device P1 will enter into a “deafened out” state S20 in which it will notbe capable to react on the subsequent transmissions of the beacon signal BA1, see stepsS22, S24, The “deafened out” state S20 will last for a certain time, which in a typicalprior art implementation is at least 30 seconds to avoid false positives due to effects inthe radio signal environment (e. g. multi-propagation delay). The “deafened out” stateS20 will often last substantially longer than 30 seconds, sometimes as long as about 15minutes depending on operational factors such as, for instance, battery level, powerconsumption or operating system scheduling in the passive mobile device.

When the “deafened out” state S20 is ended, there will again be a short beaconscanning period S30 of the monitoring performed by the passive mobile device P1. Anexit event may be reported, as seen at S26, and processed by the receiving extemaldevice (e.g. the server SS) in step S28. During the beacon scanning period S30, thepassive mobile device P1 will again be capable of detecting and reacting on asubsequent transmission S32 of the beacon signal BA1, but all of the interrnediatetransmissions S22, S24, will have been ignored.

The present inventors have identified several problems associated with theabove.

It is a problem for the host of the beacon transmitter device B1, since it willprevent the host from advertising for new or updated content. It is also a problem to thepassive mobile device P1, since it will be deprived of an opportunity to react on thebeacon signal BA1 during the period when it is “deafened out”.

This also means that when there are several beacon transmitter devices in thebeacon region, a passive mobile device will be locked to the beacon transmitter devicewhich it first discovered in the beacon region for as long as it stays within range of thatbeacon transmitter device°s beacon signal. In the example of Fig 1A, the passive mobiledevice P1 has first discovered the first beacon transmitter device B1_ It then movestowards and enters into range of the second beacon transmitter device Bg whileremaining within range of the first beacon transmitter device B1_ Since the two beacon transmitter devices B1 and Bg broadcast their beacon signals BA1 and BA; for the same CF 030~Div l beacon region (same UUID), the passive mobile device P1 will not be able to discoverthe second beacon transmitter device B; and react to its beacon signal BA;.

This is, again, problematic both from the point of view of the passive mobiledevice P1 itself and for the host of the beacon transmitter devices, for the reasonsexplained above. In addition to this, the host of the beacon transmitter devices will notbe able to track the movement of the passive mobile device P1 and broadcast an adaptedservice offer to the user of the passive mobile device P1 as a result of the movement(such as, for instance, offering a first content when the user is in a first subarea wherethe first beacon transmitter device B1 is located and a different, second content when theuser is in a second subarea where the second beacon transmitter device B; is located).

Moreover, when the mobile device app uses beacon-based localizationfunctionality for the purpose of deterrnining the location of the user with a high degreeof accuracy by means of triangulation based on several stationary beacon transmitterdevices covering the same beacon region, for instance indoors, there might be a problemif the mobile device is in passive mode. The passive mobile device P1 will not be able toupdate its estimated location caused by the movement, since the second beacon trans-mitter device B; will not be detected when the passive mobile device P1 is still withinrange of the first beacon transmitter device B1.

In recent time, applications have been introduced which are based on mobilebeacon transmitter devices rather than stationary. For instance, the present applicant hastaken leadership in developing a new beacon-based technology which considerablyfacilitates for users of mobile devices which are proximate to each other to interact by,for instance, sharing content or conducting social media interaction.

The technology, which can be referred to as a “bubble” concept, is based onshort-range wireless beacon broadcast messaging for establishing a dynamic, proximity-based network. Interaction between the users of the mobile devices in the network issupported by broadband communication with a server. Details are disclosed in theSwedish patent applications SE 1451203-2 “COMMUNICATION DEVICE FORIMPROVED SHARING OF CONTENT”, SE 1400535-9 “SELECTIVE USERINTERACTION IN A DYNAMIC, PROXIMITY-BASED GROUP OF WIRELESSCOMMUNICATION DEVICES”, SE 1451433-5 “DYNAMIC TIMING FORIMPROVED COMMUNICATION HANDLING BETWEEN COMMUNICATIONDEVICES”, SE l45 1509-2 “COMMUNICATION DEVICE FOR IMPROVEDESTABLISHING OF A CONNECTION BETWEEN DEVICES”, SE 1550486-3“TEMPORARY PROXIMITY BASED LICENSE FOR APPLICATION ACCESS” CF 030~Div 1 and SE 1551329-4 “IMPROVED ABILITY TO DETECT PASSIVE BEACONRECEIVER DEVICES IN A SHORT-RANGE WIRELESS BEACONCOMMUNICATION SYSTEM”, the contents of which are incorporated herein in theirentirety.

A short-range wireless beacon system based on mobile beacon transmitterdevices is shown in Fig 1C. While it can generally be used for various differentpurposes, the system in Fig lC is advantageously used for implementing the above-mentioned bubble concept. To this end, each mobile device A1, A2, A3, P1 is providedwith an app which (together with the operating system and hardware in the mobiledevice) is configured to handle transmission as well as reception of short-range wirelessbeacon signals. Hence, unlike the basic static beacon system in Fig 1A, in the bubblesystem of Fig lC, each mobile device can act as a beacon transmitting device as well asa beacon receiving device. In Fig lC, the mobile device A1 is in active mode andrepeatedly broadcasts its short-range wireless beacon signal BA1, containing a l28-bituniversally unique identifier UUID and a device identifier uidAl within the 32-bitmaj or/minor portion of the beacon signal.

Other active mobile devices A2, A3 within a proximity zone (range) PZ1 of themobile device BA1 can receive the beacon signal BA1, read the UUID and the uidAl,and as a result contact a system server SS over a communication network NW. The appin the receiving mobile device may decide, for instance based on user interaction, userpreference settings and/or program logic in the app, to join the bubble of the mobiledevice A1, wherein the system server SS will register the receiving mobile device asbelonging to the bubble of the mobile device A1. This is seen for the active mobiledevices A2 and A3 in Fig 1C. The users of the bubble members A1-A3 may then, forinstance, share content or conduct social media interaction supported by a system serverSS and/or a service provider SP over the communication network NW.

There may also be passive mobile devices within the proximity zone PZ1 of theactive mobile device A1. This is seen for a passive mobile device P1 in Fig 1C. Thepassive mobile device P1 will also receive the beacon signal BA1 as identified by theUUID. However, if the mobile device P1 remains in passive mode, it will not be able toreact to additional transmissions of the beacon signal BA1 from the active mobile deviceA1 for the reasons explained above with respect to Figs 1A and 1B. The passive mobiledevice P1 will therefore not be susceptive of additional tranmissions of the beacon signal BA1 from the active mobile device A1 during the “deafened out” state.

CF 030~Div 1 This problematic situation is complicated further by the fact that in a bubblesystem, all active mobile devices are potential senders as well as receivers of beaconsignals. As seen in Fig 1D, the other active mobile devices A; and A3 may also sendrespective beacon signal BA; and BA3 to generate a respective bubble of nearby mobiledevices within their respective proximity zones PZ; and PZ3. These transmissionstypically use the same common UUID, wherein the transmissions are individualized byincluding a respective device identifier uidA2 and uidA3 within the 32-bit major/minorportion of the respective beacon signal BA; and BA3.

While the active mobile devices A1 and A3 may react to the beacon signal BA;and hence join the bubble of the active mobile devices A; (and correspondingly for theactive mobile devices A1 and A; with respect to the active mobile device A3), this is notso for the passive mobile device P1 since it has already detected the beacon signal BA1of the first active mobile device A1 and thus been deafened out.

A problem from the point of view of the passive mobile device P1 is that it willnot have any opportunity to hear the beacon signals BA; or BA3 as identified by thecommon UUID and as a result not be given any opportunity to join other bubbles thanthe bubble of the first active mobile device A1. A problem from the point of view of theactive mobile devices A; and A3 is correspondingly that they will not be aware of thepresence of the passive mobile device P1 within their proximity zones PZ; and PZ3, norannounce their availability as bubble creators to the passive mobile device P1_ As is clear from the above description, the present inventor has identifiedseveral problems with beacon systems of the prior art. The inventive aspects which willbe described in the following sections of this document are generally (but notnecessarily) believed to be applicable to stationary as well as mobile beacon transmitter devices.

SUMMARY It is accordingly an object of the invention to offer improvements in thetechnical field of short-range wireless beacon communication systems, and to solve,eliminate, alleviate, mitigate or reduce at least some of the problems referred to above.

A first aspect of the present invention, not presently claimed, is a beacontransmitter device comprising a controller and a short-range wireless beacon transmitter.The controller is configured to cause a first transmission of a short-range wirelessbeacon signal by the beacon transmitter, the beacon signal identifying a beacon region, then wait during a beacon delay time period, and then cause a second transmission of CF 030~Div l the short-range wireless beacon signal by the beacon transmitter. The beacon delay timeperiod is sufficiently long to allow a short-range wireless beacon receiver device, whenbeing in a passive mode, being in range of the beacon region and having received thefirst transmission of the beacon signal, to receive and react on the second transmissionof the beacon signal.

Hence, a beacon transmitter device with improved ability to interact withpassive beacon receiver devices has been provided.

Another aspect of the present invention, not presently claimed, is a method ofbeacon transmitter device. The method involves causing a first transmission of a short-range wireless beacon signal, the beacon signal identifying a beacon region. The methodalso involves waiting during a beacon delay time period which is suff1ciently long toallow a short-range wireless beacon receiver device, when being in a passive mode,being in range of the beacon region and having received the first transmission of thebeacon signal, to receive and react on a second transmission of the beacon signal. Afterexpiry of the beacon delay time period, the method involves causing the secondtransmission of the short-range wireless beacon signal.

Accordingly, a method of operating a beacon communication system withimproved ability to interact with passive beacon receiver devices has been provided.

Still another aspect of the present invention is a beacon communication systemcomprising a plurality of beacon transmitter devices according to the first aspect of thepresent invention, wherein the first transmission of the short-range wireless beaconsignal, the waiting during the beacon delay time period, and the second transmission ofthe short-range wireless beacon signal occur essentially concurrently at the respectivebeacon transmitter devices. The beacon communication system is characterized in itsentirety by the features of any of the attached independent claims.

As a result, a beacon communication system with improved ability to interactwith passive beacon receiver devices has been provided.

Other aspects, objectives, features and advantages of the disclosed embodi-ments will appear from the following detailed disclosure, from the attached dependentclaims as well as from the drawings. Generally, all terms used in the claims are to beinterpreted according to their ordinary meaning in the technical field, unless explicitlydefined otherwise herein.

All references to "a/an/the [element, device, component, means, step, etc]" areto be interpreted openly as referring to at least one instance of the element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any CF 030~Div 1 method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

BRIEF DESCRIPTION OF DRAWINGS Figs 1A and lB illustrate a basic short-range wireless beacon system having at least one static-location beacon transmitter device and a plurality of mobile devicesacting as beacon receivers.

Figs 1C-1D illustrate an altemative short-range wireless beacon system havinga plurality of mobile devices acting as beacon transmitters as well as beacon receivers.

Figs 2A-B illustrate a general method according to the invention of operating ashort-range wireless beacon communication system with improved ability to interactwith passive beacon receiver devices, and an associated schematic timeline diagram.

Figs 3A-3C are illustrations of a chain of events occurring in a beacon systemcomprising a beacon transmitter device generally designed according to an embodimentof the system in Fig lA when being subjected to the operating method of Fig 2A.

Fig 4 is a schematic timeline diagram which illustrates an embodiment whichcan be seen as an extension of Fig 2B.

Figs 5A-5C are illustrations of a chain of events occurring in a beaconcommunication system comprising a plurality of beacon transmitter devices.

Figs 6A and 6B are schematic views of a mobile communication deviceaccording to two respective embodiments.

Fig 7 is a schematic view of components of the mobile communication devicein Figs 6A or 6B.

Fig 8 is a schematic view of a computer-readable medium.

Fig 9 is a schematic view of components of a beacon transmitter device.

DETAILED DESCRIPTION The disclosed embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the inventionare shown. This invention may, however, be embo died in many different forms andshould not be construed as limited to the embodiments set forth herein; rather, theseembodiments are provided by way of example so that this disclosure will be thoroughand complete, and will fully convey the scope of the invention to those skilled in the art.

Like numbers refer to like elements throughout.

CF 030~Div l ll Fig 2A illustrates a general method according to the invention of operating ashort-range wireless beacon transmitter device BTD1 with improved ability to interactwith passive beacon receiver devices. Fig 2B is a schematic timeline diagram for anembodiment of the method in Fig 2A. Elements in Fig 2B which contain the samereference numerals Snn as in Fig 1B have essentially the same function as alreadydescribed in the Background section for Fig lB, and the description of them is notrepeated.

The beacon transmitter device BTD1 may be a stationary beacon transmitterdevice generally of the kind shown in Figs 1A-B, or a mobile beacon transmitter devicegenerally of the kind shown in Figs lC-D, however improved in an inventive waywhich will now be explained. Exemplary implementations of the beacon transmitterdevice BTD1 are described later in this document with reference to Figs 7 and 9.

In a first step 210 in Fig 2A, the beacon transmitter device BTD1 makes a firsttransmission of a short-range wireless beacon signal BA1. This is seen at step S 12 in Fig2B. The beacon signal BAlidentifies a beacon region, as has been described in theBackground section of this document. The transmission of the short-range wirelessbeacon signal BA1 may preferably made by a short-range wireless beacon transmitter ofthe beacon transmitter device BTD1, the transmitter being implemented, for instance, bya first communication interface 732 of a wireless communication means 730 as seen inFig 7, or being implemented, for instance, by a first communication interface 932 of awireless communication means 930 as seen in Fig 9. The transmission of the short-range wireless beacon signal BA1 may be caused by a controller of the beacontransmitter device BTD1, the controller being implemented, for instance, by a controller710 as seen in Fig 7, or being implemented, for instance, by a controller 910 as seen inFig 9.

In a second step 220 in Fig 2A, (the controller of) the beacon transmitter deviceBTD1 Waits during a beacon delay time period BDTP. This is seen at S18 in Fig 2B.The beacon delay time period BDTP is sufficiently long to allow a short-range wirelessbeacon receiver device P1, when being in a passive mode, being in range of the beaconregion and having received the first transmission of the beacon signal, to receive andreact (see S34 in Fig 2B) on a second transmission of the beacon signal BA1. The short-range wireless beacon receiver device P1 is typically a passive mobile device generallyof the kind shown in and described above for Figs 1A-D.

Hence, the beacon transmitter device BTD1 makes no further transmissions of the beacon signal BA1 during the beacon delay time period BDTP, which is selected, CF 030~Div l 12 chosen, designed or otherwise defined to last at least as long as the “deafened out” stateS20 of the passive mobile device P1_ This is in contrast to the frequent subsequenttransmissions of the beacon signal at steps S22, S24, ..., in the prior art according to FiglB.

Then, after the waiting step 220, in a third step 230 in Fig 2A, the beacontransmitter device BTD1 makes a subsequent second transmission of the short-rangewireless beacon signal BA1, see step S32 in Fig 2B. Again, the transmission may becaused by the aforementioned controller.

Thanks to the waiting in step 220/ S18 during the beacon delay time periodBDTP, the subsequent second transmission of the beacon signal BA1 will - as seen atS32 in Fig 2B - occur when the “deafened out” state S20 of the passive mobile deviceP1 has ended and a new beacon scanning period S30 of the monitoring has commenced.This will allow the short-range wireless beacon receiver device P1 to receive and react(step S34) on the second transmission of the beacon signal BA1, for instance in the sameway or a way similar to how it reacted on the first transmission of the beacon signalBA1.

As will be understood from the above, the beacon delay time period BDTP isadvantageously defined to be at least equal to an expected duration it would take for theshort-range wireless beacon receiver device P1, after having received a first transmissionof the beacon signal BA1, to become capable of receiving and reacting on a subsequentsecond transmission of the beacon signal BA1.

Figs 3A-3C illustrate what happens to the beacon system as seen in Fig lA (thebeacon transmitter device BTD1 being the stationary beacon transmitter device B1) orFig lC (the beacon transmitter device BTD1 being the mobile device A1) whensubjected to the operating method of Fig 2A. The situation in step 2l0 is represented byFig 3A; the beacon transmitter device BTD1 makes the first transmission of the short-range wireless beacon signal BA1. Active mobile device A1, A2, A3 and passive mobiledevice P1 may receive and react upon the beacon signal BA1, and passive mobile deviceP1 will then be “deafened out” for some time as previously discussed.

The situation in step 220 is represented by Fig 3B. Here, the beacon transmitterdevice BTD1 suspends transmission of the short-range wireless beacon signal during thebeacon delay time period BDTP.

The situation in step 230 is represented by Fig 3C where the beacon transmitterdevice BTD1 resumes transmission of the short-range wireless beacon signal. Thanks to the waiting during the beacon delay time period BDTP, the subsequent second trans- CF 030~Div 1 13 mission of the beacon signal BA1 in Fig 3C is likely to occur When the passive mobiledevice P1 is no longer deafened out.

In one embodiment, the (controller of the) beacon transmitter device BTD1 isconfigured to operate on a periodic basis, such that after the transmission of the secondtransmission of the beacon signal BA1, the controller Will Wait during the beacon delaytime period BDTP and then cause a third transmission of the short-range Wirelessbeacon signal BA1 by the beacon transmitter, and so on.

The duration of the beacon delay time period BDTP may be configurable. Inone embodiment, this may be done by the (controller of the) beacon transmitter deviceBTD1 receiving beacon delay control data BDCD from an extemal device (such as aservice provider SP or a system server SS) via a communication interface. See 310 inFig 3A. The communication interface may, for instance, be implemented by a secondcommunication interface 734 of the Wireless communication means 730 as seen in Fig7, or by a second communication interface 934 of the Wireless communication means930 as seen in Fig 9.

The (controller of the) beacon transmitter device BTD1 Will derive a timervalue from the received beacon delay control data, and set the duration of the beacondelay time period BDTP to the derived timer value.

In an altemative embodiment, the duration of the beacon delay time periodBDTP is not fixed a priori. Instead, the end of the beacon delay time period BDTP maybe controlled from an extemal device (such as the service provider SP or the systemserver SS) via the aforementioned communication interface. See 320 in Fig 3B. The(controller of the) beacon transmitter device BTD1 Will receive a beacon transmissionresumption command BTRC from the extemal device. In response, the (controller ofthe) beacon transmitter device BTD1 Will terrninate the beacon delay time period BDTPand cause the second transmission of the short-range Wireless beacon signal BA1 by thebeacon transmitter.

In yet an altemative embodiment, the duration of the beacon delay time periodBDTP is not fixed a priori. Instead, the end of the beacon delay time period BDTP maybe controlled by the beacon transmitter device BTD1 by enquiring an extemal device(such as the service provider SP or the system server SS) via the aforementionedcommunication interface. This is illustrated in Fig 4 Which can be seen as an extensionof Fig 2B (again, the same reference numerals represent essentially the same elements/ functionality).

CF 030~Div 1 14 In Fig 4, the (controller of the) beacon transmitter device BTD1 sends in stepS21 an inquiry Enq_heard (BTD1) to the external device SS, SP Via the communicationinterface. The inquiry is sent during the beacon delay time period BDTP.

In response, the (controller of the) beacon transmitter device BTD1 receives instep S23 a response Resp_heard from the external device SS, SP via the communicationinterface.

The (controller of the) beacon transmitter device BTD1 then deterrninesWhether the received response indicates presence of at least one short-range Wirelessbeacon receiver device, being in the passive mode, having received the firsttransmission S 12 of the beacon signal BA1, having reported S 14 an entry event for thebeacon region as identified by the beacon signal BA1 to the extemal device SS, SP butnot having reported an exit event for the beacon region to the extemal device.

If the deterrnination is affirmative, the (controller of the) beacon transmitterdevice BTD1 continues the beacon delay time period BDTP. This is seen for thereceived inquiry response Resp_heard (BTD1, P1, NoExit) in step S23 of Fig 4. Thebeacon transmitter device BTD1 is hence inforrned that there is indeed a passive mobiledevice P1 Which has reported an entry event but not an exit event for the monitoredbeacon region. The beacon transmitter device BTD1 may thus conclude that the passivemobile device P1 is probably deafened out and that the beacon delay time period BDTPshould continue.

The passive mobile device P1 then reports an exit event to the extemal deviceSS, SP in step S26, and the extemal device SS, SP registers this in step S28, aspreviously described.

The (controller of the) beacon transmitter device BTD1 then sends in step S29another inquiry Enq_heard (BTD1) to the extemal device SS, SP via the communicationinterface. The inquiry is still sent during the beacon delay time period BDTP.

In response, the (controller of the) beacon transmitter device BTD1 receives instep S31 a response Resp_heard from the extemal device SS, SP via the communicationinterface.

The (controller of the) beacon transmitter device BTD1 then deterrninesWhether the received response indicates presence of at least one short-range Wirelessbeacon receiver device, being in the passive mode, having received the firsttransmission S 12 of the beacon signal BA1, and having reported an entry event S 14 asWell as an exit event S26 for the beacon region as identified by the beacon signal BA1 tothe extemal device SS, SP.

CF 030~Div 1 If the deterrnination is aff1rmative, the (controller of the) beacon transmitterdevice BTD1 terrninates the beacon delay time period BDTP, and causes the secondtransmission S32 of the short-range Wireless beacon signal BA1 by the beacontransmitter 732; 932. This is seen for the received inquiry response Resp_heard (BTD1,P1, ExitDone) in step S31 of Fig 4. The beacon transmitter device BTD1 is henceinforrned that there is indeed a passive mobile device P1 Which has reported an entryevent as Well as an exit event for the monitored beacon region. The beacon transmitterdevice BTD1 may thus conclude that the passive mobile device P1 is not deafened outanymore and that the beacon delay time period BDTP should be terrninated.

A beacon communication system may comprise a plurality of beacontransmitter devices, each essentially operating as has been described above. Figs 5A-Cillustrates one embodiment of such a beacon communication system, comprising threebeacon transmitter devices BTD1, BTDg, BTD3 (the number of beacon transmitterdevices in a beacon communication system may of course be less than or more thanthree depending on implementation). The beacon transmitter devices BTD1, BTDQ,BTD; are operative to transmit short-range Wireless beacon signals BA1, BA; and BA3.The first transmission 210 of the respective short-range Wireless beacon signal BA1,BA; or BA3, the Waiting 220 during the beacon delay time period BDTP, and the secondtransmission 230 of the respective short-range Wireless beacon signal BA1, BA; or BA3occur essentially concurrently at the beacon transmitter devices BA1, BA; and BA3.

This is benef1cial, since it Will reduce the risk that a passive mobile device inrange of the beacon region (but not shown in Figs 5A-C for reasons of brevity) Wouldbe deafened out to an extent Where it could not be reached for a long time after itdetected the first transmission 210 of one of the short-range Wireless beacon signals,because the first transmissions 210 of the other short-range Wireless beacon signalsWould in effect prolong the deafened out period (if the passive mobile device staysWithin the beacon region).

To this end, in one embodiment an extemal device such as a server SS, SP isconfigured to periodically send a beacon transmission synchronization signal BTSS tothe beacon transmitter devices BTD1, BTDQ, BTD3. More specif1cally, the afore-mentioned controller 710, 910 of each beacon transmitter device BTD1, BTDQ, BTD; isconf1gured to receive a first beacon transmission synchronization signal BTSS from theextemal device SS, SP via the aforementioned communication interface. This is seen at 510 in Fig 5A. In response, the controller of each beacon transmitter device BTD1, CF 030~Div 1 16 BTDZ, BTD3 is configured to cause the aforementioned first transmission 210 of theshort-range Wireless beacon signal BA1, BA; or BA; by the beacon transmitter 732; 932.

The beacon transmitter devices BTD1, BTDg, BTD3 Will then Wait 220 during abeacon delay time period BDTP in Which no beacon signals BA1, BA; or BA3 are sent.This is seen in Fig 5B.

The end of the beacon delay time period BDTP Will not need to be defined apriori. Instead, the controller of each beacon transmitter device BTD1, BTDZ, BTD; isconfigured to receive a second beacon transmission synchronization signal BTSS fromthe extemal device SS, SP via the communication interface, and in response cause thesecond transmission 230 of the short-range Wireless beacon signal by the beacontransmitter 732; 932 as seen in Fig 5C - thereby in effect ending the beacon delay timeperiod BDTP.

In one embodiment, the beacon transmission synchronization signal BTSS canimplement the beacon transmission resumption command BTRC Which has beendescribed above for Fig 3B.

As an altemative to extemal synchronization, the beacon transmitter devicesBTD1, BTD2, BTD3 can themselves keep track of the duration of the beacon delay timeperiod BDTP by using a current time value. In such an embodiment, the controller 710,910 of each beacon transmitter device BTD1, BTDg, BTD3 may be configured to obtaina current time value from either a local clock provided in the beacon transmitter deviceor an extemal time keeping service accessible via the communication interface. If localclocks are used, they should be synchronized by some available means, such as acommon time reference accessible via the communication interface.

The controller 710, 910 of each beacon transmitter device BTD1, BTD2, BTD3may further be configured to determine Whether the obtained time value indicates that atleast a time corresponding to the beacon delay time period BDTP has elapsed since thefirst transmission 210 of the short-range Wireless beacon signal BA1-BA3 by the beacontransmitter 732, 932. If the deterrnination is affirmative, the controller Will cause thesecond transmission 230 of the short-range Wireless beacon signal by the beacontransmitter.

One exemplary but beneficial use of a synchronized beacon communicationsystem according to the invention is to track the movement of mobile devices (includingpassive mobile devices) as they are carried around in a shop, mall, sports arena, etc.Every time the first or second transmission of the beacon signals BA1-BA3 occurs from a beacon transmitter device BTD1, BTDg, BTD; in the beacon region, the mobile CF 030~Div l 17 devices may report this to an external device such as the server SS, SP. By usinginforrnation obtained by beacon ranging, the external device may then deterrnine acurrent relative location of each mobile device in the shop, mall, sports arena, etc. (forinstance by triangulation), and in response take appropriate action. Such action may forinstance involve offering the individual mobile device a customized content dependingon the current relative location of the mobile device, its movement behavior, etc.

Figs 6A and 6B generally show a mobile, or wireless, communication device600 which may implement any of the mobile devices Al-Ag, P1 referred to above.Referring to Fig 6A, the wireless communication device is a mobile telecommuni-cations terminal in the form of a smartphone or a tablet computer (arranged with awireless communication interface), comprising a housing 6l0 in which a display 620 isarranged. In one embodiment the display 620 is a touch display. In other embodimentsthe display 620 is a non-touch display. Furthermore, the smartphone 600 comprises twokeys 63 0a, 63 0b. In this embodiment there are two keys 630, but any number of keys ispossible and depends on the design of the smartphone 600.

In one embodiment the smartphone 600 is configured to display and operate avirtual key 635 on the touch display 620. It should be noted that the number of virtualkeys 635 depends on the design of the smartphone 600 and an application that isexecuted on the smartphone 600. The smartphone 600 may also be equipped with acamera 660. The camera 660 may be a digital camera that is arranged to take video orstill photographs by recording images on an electronic image sensor (not shown). In oneembodiment the camera 660 may be an extemal camera. In one embodiment the cameramay altematively be replaced by a source providing an image stream. The smartphone600 may also be equipped with a loudspeaker 640 and a microphone 645.

Referring to Fig 6B, a laptop computer 600 comprises a display 620 and ahousing 6l0. The housing comprises a controller or CPU (not shown) and one or morecomputer-readable storage media (not shown), such as storage units and intemalmemory. Examples of storage units are disk drives or hard drives. The laptop computer600 further comprises at least one data port. Data ports can be wired and/or wireless.Examples of data ports are USB (Universal Serial Bus) ports, Ethemet ports or WiFi(according to IEEE standard 802.11) ports. Data ports are configured to enable thelaptop computer 600 to connect with other computing devices or a server.

The laptop computer 600 further comprises at least one input unit such as akeyboard 630. Other examples of input units are computer mice, touch pads, touch screens or joysticks, to name a few.

CF 030~Div l 18 The laptop computer 600 may further be equipped with a camera 660. Thecamera 660 may be a digital camera that is arranged to take video or still photographsby recording images on an electronic image sensor (not shown). In one embodiment thecamera 660 may be an extemal camera. In one embodiment the camera may altemati-vely be replaced by a source providing an image stream. The laptop computer 600 mayalso be equipped with a loudspeaker 640 and a microphone 645. The wirelesscommunication device 600 according to Fig 6A or Fig 6B may be configured to detectand track an object, for instance a hand of a user, via the camera 660.

Fig 7 shows a schematic view of the general structure of a communicationdevice according to Fig 6A or Fig 6B. The device 700 comprises a controller 7l0 whichis responsible for the overall operation of the wireless communication device 700 and ispreferably implemented by any commercially available CPU ("Central ProcessingUnit"), DSP ("Digital Signal Processor") or any other electronic programmable logicdevice. The controller 7l0 is configured to read instructions from a memory 740 andexecute these instructions to control the operation of the wireless communication device200. The memory 740 may be implemented using any commonly known technology forcomputer-readable memories such as ROM, RAM, SRAM, DRAM, CMOS, FLASH,DDR, SDRAM or some other memory technology. The memory 740 is used for variouspurposes by the controller 7l0, one of them being for storing application data andprogram instructions 750 for various software modules in the wireless communicationdevice 700. The software modules may include a real-time operating system, drivers fora user interface 720, an application handler as well as various applications 750.

The wireless communication device 700 fiarther comprises the user interface720, which in the devices 700 of Figs 6A and 6B is comprised of the display 620 andthe keys 630, 635. The user interface may also comprise the microphone 645 and theloudspeaker 644.

The wireless communication device 700 further comprises wireless com-munication means 730, which is adapted to allow the wireless communication device700 to communicate with other devices through the use of different radio frequencytechnologies. More specifically, the wireless communication means 730 comprises afirst communication interface 732 for short-range wireless beacon broadcast messaging.The first communication interface 732 may implement the short-range wireless beacontransmitter as referred to previously in this document and may, advantageously, beimplemented as an iBeacon and/or Bluetooth Low Energy (BLE)/Bluetooth 4.0 compliant communication interface.

CF 030~Div 1 19 Moreover, the wireless communication means 730 comprises a secondcommunication interface 734 for communicating with a server like the system server SSand/or the service provider SP via the communication network NW. The communi-cation with the server typically occurs at a substantially higher bandwidth than theshort-range wireless beacon broadcast messaging. The server may be a standalonecomputing resource extemal to the wireless communication device 700, a cloud-based(distributed) computing resource, or, in alternative embodiments, implemented at leastpartly in and by the wireless communication device 700. The second communicationinterface 734 may, advantageously, be implemented as a communication interfacecompliant with IEEE 802.11, IEEE 802.15, ZigBee, WirelessHART, WiFi, Bluetooth®,WCDMA, HSPA, GSM, UTRAN, UMTS, and LTE, to name a few. It should be notedthat, as is commonly known, the wireless communication means 730 may be arrangedto communicate according to more than one technology and many differentcombinations may therefore be available; for example, a smartphone is commonlyarranged to communicate according to the Bluetooth® standard, the WiFi standard andthe LTE standard.

The wireless communication device 700 is further equipped with a camera 760.The camera 760 is a digital camera that is arranged to take video or still photographs byrecording images on an electronic image sensor (not shown). The camera 760 isoperably connected to the controller 710 to provide the controller with a video stream765, i.e. the series of images captured, for further processing possibly for use in and/oraccording to one or several of the applications 750. In one embodiment the camera 760is an extemal camera or source of an image stream.

Fig 9 shows a schematic view of the general structure of a communicationdevice 900 which may implement any of the beacon transmitter devices B1 or B1 asdescribed herein. The device 900 comprises a controller 910 which is responsible for theoverall operation of the wireless communication device 900 and is preferablyimplemented by any commercially available CPU ("Central Processing Unit"), DSP("Digital Signal Processor") or any other electronic programmable logic device. Thecontroller 910 is configured to read instructions from a memory 940 and execute theseinstructions to control the operation of the wireless communication device 900. Thememory 940 may be implemented using any commonly known technology forcomputer-readable memories such as ROM, RAM, SRAM, DRAM, CMOS, FLASH,DDR, SDRAM or some other memory technology. The memory 940 is used for variouspurposes by the controller 910, one of them being for storing application data and CF 030~Div 1 program instructions 750 for software which def1nes the device°s 900 operating as abeacon transmitting device.

The wireless communication device 900 fiarther comprises wireless com-munication means 930, which is adapted to allow the wireless communication device900 to communicate with other devices. More specifically, the wireless communicationmeans 930 comprises at least a first communication interface 932 which supports short-range wireless beacon broadcast messaging and may, advantageously, be implementedas an iBeacon® and/or Bluetooth Low Energy (BLE)/Bluetooth 4.0 compliantcommunication interface. The first communication interface 932 may implement theshort-range wireless beacon transmitter as referred to previously in this document.

The wireless communication means 930 may also comprise a second com-munication interface 934 for communicating with a server like the system server SSand/or the service provider SP via the communication network NW. The second com-munication interface 934 will receive the refresh control data RCD when applicable andmay, advantageously, be implemented as a communication interface compliant withIEEE 802.11, IEEE 802.15, ZigBee, WirelessHART, WiFi, Bluetooth®, WCDMA,HSPA, GSM, UTRAN, UMTS, and LTE, to name a few.

References to 'computer-readable storage medium', 'computer programproduct', 'tangibly embodied computer program' etc. or a 'controller', 'computer','processor' etc. should be understood to encompass not only computers having differentarchitectures such as single /multi- processor architectures and sequential (VonNeumann)/parallel architectures but also specialized circuits such as field-programmable gate arrays (FPGA), application specific circuits (ASIC), signalprocessing devices and other devices. References to computer program, instructions,code etc. should be understood to encompass software for a programmable processor orfirmware such as, for example, the programmable content of a hardware device whetherinstructions for a processor, or configuration settings for a fixed-fianction device, gatearray or programmable logic device etc.

Fig 8 shows a schematic view of a computer-readable medium as described inthe above. The computer-readable medium 830 is in this embodiment a data disc 830. Inone embodiment the data disc 830 is a magnetic data storage disc. The data disc 830 isconfigured to carry instructions 831 that when loaded into a controller, such as aprocessor, executes a method or procedure according to the embodiments disclosedabove. The data disc 830 is arranged to be connected to or within and read by a reading device 832, for loading the instructions into the controller. One such example of a CF 030~Div l 21 reading device 832 in combination with one (or several) data disc(s) 830 is a hard drive.It should be noted that the computer-readable medium can also be other media such ascompact discs, digital video discs, flash memories or other memory technologiescommonly used.

The instructions 83l may also be downloaded to a computer data readingdevice 834, such as a laptop computer or other device capable of reading computercoded data on a computer-readable medium, by comprising the instructions 83l in acomputer-readable signal 833 which is transmitted via a wireless (or Wired) interface(for example via the Intemet) to the computer data reading device 834 for loading theinstructions 83l into a controller. In such an embodiment the computer-readable signal833 is one type of a computer-readable medium 830. The instructions may be stored ina memory (not shown explicitly in Fig 8, but referenced as 740 in Fig 8) of thecomputer data reading device 834.

References to computer program, instructions, code etc. should be understoodto encompass software for a programmable processor or firmware such as, for example,the programmable content of a hardware device whether instructions for a processor, orconfiguration settings for a fixed-function device, gate array or programmable logicdevice etc.

The various functionality described in this document may be performed in partor fully in a wireless communication device 700 or 900 comprising a controller asdisclosed above with reference to Figs 6A, 6B, 7 and 9, and/or caused to be performedby executing instructions stored on a computer-readable medium as disclosed withreference to Fig 8.

The location of applications programs, or apps, as referred to in this documentwith respect to a hierarchical software model is not critical; hence, they may be locatedat an application layer or altematively at a lower layer, such as for instance being part ofan operating system.

Even though the embodiments described above are based on beacon systemswhere a beacon region is represented by a universally unique identifier (UUID), theinvention may be applied also to other types of beacon systems. For instance, theinvention may be applied to beacon system like AltBeacon, URIBeacon and Eddystone,which do not use a UUID but another form of identity (such as a tiny URL) in the 3 l-byte GAP BLE packet for the beacon signal.

The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other CF 030~Div l 22 ernbodirnents than the ones disclosed above are equally possible Within the scope of the invention, as defined by the appended patent clairns.

Claims (8)

1. A beacon communication system comprising a plurality of beacontransmitter devices (BTD1, BTDQ, BTD3, 700; 900), each beacon transmitter devicecomprising a controller (710; 910) and a short-range Wireless beacon transmitter (732;932), the controller being conf1gured to cause a first transmission (S12) of a short-rangeWireless beacon signal (BA1) by the beacon transmitter, the beacon signal identifying abeacon region, Wait during a beacon delay time period (BDTP), and cause a secondtransmission (S32) of the short-range Wireless beacon signal (BA1) by the beacontransmitter, Wherein the beacon delay time period (BDTP) is suff1ciently long to alloW ashort-range Wireless beacon receiver device (P1), When being in a passive mode, beingin range of the beacon region and having received the first transmission of the beaconsignal, to receive and react (S34) on the second transmission of the beacon signal,Wherein the first transmission of the short-range Wireless beacon signal (BA1-BA3), theWaiting during the beacon delay time period (BDTP), and the second transmission ofthe short-range Wireless beacon signal occur essentially concurrently at the respectivebeacon transmitter devices, the beacon communication system further comprising anextemal device (SS, SP), each beacon transmitter device (BTD1, BTDQ, BTD3, 700;900) having a communication interface (734; 934) for data communication, Wherein: the extemal device is configured to periodically send a beacon transmissionsynchronization signal (BTSS) to the beacon transmitter devices (BTD1, BTDQ, BTD3,700; 900); and Wherein the controller (710; 910) of each beacon transmitter device (BTD1, BTDz,BTDg, 700; 900) is further configured to: receive a first beacon transmission synchronization signal (510) from theextemal device (SS, SP) via the communication interface; cause the first transmission of the short-range Wireless beacon signal (BA1-BA3) by the beacon transmitter (732; 932); receive a second beacon transmission synchronization signal (530) from theextemal device (SS, SP) via the communication interface; and cause the second transmission of the short-range Wireless beacon signal by thebeacon transmitter (732; 932).

2. A beacon communication system comprising a plurality of beacontransmitter devices (BTD1, BTDQ, BTD3, 700; 900), each beacon transmitter device CF 030~Div 1 24 comprising a controller (710; 910) and a short-range Wireless beacon transmitter (732;932), the controller being conf1gured to cause a first transmission (S12) of a short-rangeWireless beacon signal (BA1) by the beacon transmitter, the beacon signal identifying abeacon region, Wait during a beacon delay time period (BDTP), and cause a secondtransmission (S32) of the short-range Wireless beacon signal (BA1) by the beacontransmitter, Wherein the beacon delay time period (BDTP) is sufficiently long to alloW ashort-range Wireless beacon receiver device (P1), When being in a passive mode, beingin range of the beacon region and having received the first transmission of the beaconsignal, to receive and react (S34) on the second transmission of the beacon signal,Wherein the first transmission of the short-range Wireless beacon signal (BA1-BA3), theWaiting during the beacon delay time period (BDTP), and the second transmission ofthe short-range Wireless beacon signal occur essentially concurrently at the respectivebeacon transmitter devices, each beacon transmitter device (BTD1, BTDQ, BTD3, 700;900) having a communication interface (734; 934) for data communication, Wherein:the controller (710; 910) of each beacon transmitter device (BTD1, BTDz,BTDg, 700; 900) is further configured to:obtain a current time value from either a local clock provided in the beacontransmitter device or an extemal time keeping service accessible via the communicationinterface;determine Whether the obtained time value indicates that at least a timecorresponding to the beacon delay time period (BDTP) has elapsed since the firsttransmission of the short-range Wireless beacon signal (BA1-BA3) by the beacontransmitter (732; 932); andif the deterrnination is affirmative, cause the second transmission of the short- range Wireless beacon signal by the beacon transmitter.

3. The beacon communication system according to claim 1 or 2, Wherein thebeacon delay time period (BDTP) is defined to be at least equal to an expected durationit Would take for the short-range Wireless beacon receiver device (P1), after havingreceived the first transmission of the beacon signal, to become capable of receiving and reacting on the second transmission of the beacon signal.

4. The beacon communication system according to any of claims 1 to 3,Wherein the controller (710; 910) is configured to operate on a periodic basis, such that after the transmission of the second transmission of the beacon signal, the controller CF 030~Div 1 Waits during the beacon delay time period (BDTP) and then causes a third transmissionof the short-range Wireless beacon signal (BA1) by the beacon transmitter (732; 932), and so on.

5. The beacon communication system according to claim 1 or 2, Wherein thecontroller (710; 910) is further configured to: receive beacon delay control data (BDCD) from an extemal device (SS, SP)via the communication interface; derive a timer value from the received beacon delay control data; and set the duration of the beacon delay time period (BDTP) to the derived timer value.

6. The beacon communication system according to claim 1 or 2, Wherein thecontroller (710; 910) is further configured to: receive a beacon transmission resumption command (BTRC) from an extemaldevice (SS, SP) via the communication interface; terrninate the beacon delay time period (BDTP); and cause the second transmission of the short-range Wireless beacon signal (BA1)by the beacon transmitter (732; 932).

7. The beacon communication system according to claim 1 or 2, Wherein thecontroller (710; 910) is further configured to: send (S21) an inquiry (Enq_heard) to an extemal device (SS, SP) via thecommunication interface; receive (S23) a response (Resp_heard) from the extemal device (SS, SP) viathe communication interface; determine Whether the received response indicates presence of at least oneshort-range Wireless beacon receiver device (P1), being in the passive mode, havingreceived the first transmission of the beacon signal, having reported an entry event forthe beacon region as identified by the beacon signal to the extemal device but nothaving reported an exit event for the beacon region to the extemal device; and if the deterrnination is affirmative, continue (S18) the beacon delay time period(BDTP). CF 030~Div 1 26

8. The beacon communication system according to claim 1 or 2, Wherein thecontroller (7 l 0; 910) is further configured to: send (S29) an inquiry (Enq_heard) to an extemal device (SS, SP) via thecommunication interface; receive (S31) a response (Resp_heard) from the extemal device (SS, SP) viathe communication interface; determine Whether the received response indicates presence of at least oneshort-range Wireless beacon receiver device (P1), being in the passive mode, havingreceived the first transmission of the beacon signal, and having reported an entry eventas Well as an exit event for the beacon region as identified by the beacon signal to theextemal device; and if the deterrnination is affirmative: terrninate the beacon delay time period (BDTP); andcause (S32) the second transmission of the short-range Wirelessbeacon signal (BA1) by the beacon transmitter (732; 932).