SYNCHRONIZATION OF A MOBILE DEVICE AND A PEER DEVICE FOR UWB-BASED COMMUNICATION

Abstract

It is described a method of UWB-based communication between a mobile device (101, 401) and at least one peer device (102, 402a,b,c), the method comprising while the mobile device (101, 401) is in an idle mode: a synchronizing step (410) including that the mobile device (401) sends at least one synchronization message (418) without performing full Ranging cylce; the peer device (402) receiving the synchronization message (418); and the peer device (402) synchronizing with the mobile device (410) based on the received synchronization message (418); the method comprising while the mobile device (401) is in a non-idle mode: the mobile device starting a UWB-based DS-TWR session (425, 525, 526) with the synchronized peer device, in order to control the smart-device (402c, 502c) via the mobile device.

Claims

1. Method of UWB-based communication between a mobile device, in particular hand carried device (101, 401), and at least one peer device, in particular smart device (102, 402a,b,c), the method comprising while the mobile device (101, 401) is in an idle mode: a synchronizing step (410) including that the mobile device (401) sends at least one synchronization message (418) without performing full ranging cycle, in particular DS-TWR multicast; the peer device (402) receiving the synchronization message (418); and the peer device (402) synchronizing with the mobile device (410) based on the received synchronization message (418); the method comprising while the mobile device (401) is in a non-idle mode: the mobile device starting a UWB-based ranging cycle, in particular DS-TWR session (425, 525, 526), with the synchronized peer device, in order to control the smart-device (402c, 502c) via the mobile device.

2. Method according to the preceding claim, wherein the synchronization step comprises: transmitting subsequent UWB-based synchronization control messages, in particular RCM messages (418a,b,c,d), from the mobile device to the peer device without transmitting any other messages in between, wherein the synchronization control messages include information that a standard ranging round should not be performed.

3. Method according to the preceding claim, wherein the subsequent synchronization control messages (418a,b,c,d) are transmitted at regular points in time, in order to keep the peer device synchronized with the mobile device.

4. Method according to any one of the preceding claims, further comprising: indicating at the mobile device (101) and at the peer device (102) that both devices are synchronized.

5. Method according to any one of the preceding claims, wherein the mobile device (401) enters a power saving mode, after the mobile device having transmitted the synchronization message (418); wherein the peer device (402c) enters a power saving mode, after the peer device having received the synchronization message (418).

6. Method according to any one of the preceding claims, wherein the peer device (102) comprises an IoT device, wherein the mobile device (101) comprises a smart phone.

7. Method according to any one of the preceding claims, wherein the idle mode of the mobile device (101) comprises a user interaction screen being inactive.

8. Method according to any one of the preceding claims, wherein the ranging cycle, in particular DS-TWR session (425, 525, 526), is started, while the mobile device (501) is non-idle and the mobile device is pointing to the smart-device (502c) within a defined angle range and within a defined distance range.

9. Method according to any one of the preceding claims, wherein ranging cylce (425, 525, 526) comprises: the mobile device transmitting at least one of: a RCM, a Poll-message, a Final-message, and a Final Data-message; the peer device transmitting at least one of: a response after a poll-message by the mobile device, a report-message, a RCR-message, a RIUM-message, and/or wherein the ranging cycle comprises: DS-TWR or SS-TWR.

10. Method according to the preceding claim, wherein the transmission is in a SP1-frame or SP0-frame, wherein at least one transmission frame is extended, in order to accompany application data.

11. Method according to any one of the preceding claims, the method comprising, for initial synchronization (109) during the synchronization step: the peer device (102) sending advertisement messages (112) using bluetooth-based transmission; the mobile device (101) receiving at least one of the advertisement messages (112) and connecting to the peer device via a bluetooth-based protocol; and the mobile device (101) establishing a bluetooth-based synchronization with the peer device (102).

12. Method according to the preceding claim, wherein the bluetooth-based protocol comprises a BLE-protocol, wherein the bluetooth-based synchronization between the mobile device and the peer device allows for accurate time synchronization, in particular having a timing-error being less than 5 ms.

13. Method according to any one of the preceding claims, further comprising: at least one other the peer device (402a,b) receiving the synchronization message (418); and the at least one other peer device (402a,b) synchronizing with the mobile device (401) based on the received synchronization message; the method comprising while the mobile device is in a non-idle mode: the mobile device starting a UWB-based DS-TWR session with the synchronized at least one other peer device, in order to control the at least one other smart-device via the mobile device.

14. Method according to any one of the preceding claims, further comprising: at least one other mobile device transmitting at least one other synchronization message without performing full ranging cylce; at least one peer device receiving the other synchronization message; and the peer device synchronizing with the other mobile device based on the received other synchronization message; the method comprising while the other mobile device is in a non-idle mode: the other mobile device starting a UWB-based DS-TWR session with the synchronized peer device, in order to control the smart-device via the other mobile device.

15. System (100, 400, 500) of UWB-based communication, comprising: at least one mobile device (101, 401, 501); and at least one peer device (102, 402, 502), wherein the at least one mobile device and the at least one peer device are configured to carry out a method according to one of the preceding claims.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIGS. 1 to 7 schematically illustrate particular embodiments of a system of UWB-based communication, according to embodiments, wherein the figures illustrate communication messages exchanged by the communication partners.

DETAILED DESCRIPTION OF THE DRAWINGS

[0038] Embodiments of the present technology are now described referring to the figures. The invention is not restricted to the illustrated or described embodiments.

[0039] It should be understood that features or units in the different figures which are similar or same in structure and/or function are labelled with reference signs which differ only in the first digit. A description of one element or structure not described with reference to a particular figure may be taken from the respective description according to another embodiment or figure.

[0040] The system 100 of UWB-based communication according to an embodiment of the present technology comprises at least one mobile device 101 and at least one peer device, such as smart device 102 which are both UWB-enabled. The mobile device 101 comprises a UWB controller 103 as well as a host 104. The mobile device 101 further comprises a BLE unit 105 which is enabled to perform bluetooth low energy communications. The smart device 102 comprises a UWB controller 106 as well as a host 107 and a BLE unit 108.

[0041] In the embodiment illustrated in FIG. 1, the system 100 is configured to carry out a first phase 109 and a third and fourth phase 111. A second phase including a synchronization step is omitted in FIG. 1. During the first phase 109, an initial synchronization is performed using the BLE communication technology. Thereby, the smart device 102 sends using the BLE unit 108 advertisement messages 112 using bluetooth-based transmission. The mobile device 101 (in scan mode 114) receives at least one of the advertisement messages 112 and connects to the smart device 102 via a bluetooth-based protocol. Thereby, the mobile device 101 establishes a bluetooth-based synchronization with the smart device as indicated by the message 113.

[0042] In particular, the smart device 102 may permanently send advertisement messages 112 at the BLE-link. The mobile device 101 which receives one of the advertisement messages 112 will then connect to the smart device 102, since it may send scan messages 114. The advertisement messages 112 are received at the BLE unit 105 and transmitted in response messages 115 to the host unit 104. The host unit 104 then starts a session via the BLE layer 105 (see message 116).

[0043] During the third and fourth phase 111, the mobile device may initiate first and then start a multicast DS-TWR session, in particular as soon as a single smart device is found at a defined time interval. Therein, the third and fourth phase 111 comprises a portion 117 to exchange session ID, to configure and to range, before performing a multicast DS-TWR session 126.

[0044] The smart device 102 may continuously search for additional mobile devices which may allow for multiple users to connect to the same smart device 102.

[0045] FIG. 2 schematically illustrates a system 200 according to another embodiment, in particular during a third and fourth phase 211 (and second phase 210) of a method of communication. A mobile device 201 is close to plural smart devices 202a, 202b, 202c. For synchronization, the mobile device 201 sends an RCM message 218. The synchronization or the RCM message 218 may be an example of a synchronization message sent or transmitted by the mobile device 201. Thus, the synchronization or the RCM message 218 may be transmitted during a second phase 210 providing a synchronization between the mobile device 201 and one of the smart devices 202a,b,c. In other embodiments, synchronization may be provided by the first phase 109 as depicted in FIG. 1.

[0046] The mobile device 201 may start multicast DS-TWR session, as soon as a single smart device is found at a defined time base. The block duration may be 1000 ms, the fixed slot alignment as aligned in the BLE establishment phase along with adding and removing devices may be applied. The smart device 202a,b,c may then synchronize on the multicast session. During the ranging cycle, in particular DS-TWR multicast, the RCM message 218 may be sent by the mobile device 201. Then, a Poll-message 219 may be sent by the mobile device 201. The smart device 202a may transmit a response message 220a which may be received by the mobile device 201. Other response messages 220b, 220c may be transmitted by the other smart devices 202b, 202c. The mobile device 201 may transmit a Final-message 221 to the smart device 202c and may then transmit a Final Data-message 222 to the smart device 202c.

[0047] During a reporting phase 223, the different smart devices 202a, 202b, 202c may transmit report messages 224a,b,c to the mobile device 201. Further, the smart device 202c may transmit a RCR-message 225 which is received at the mobile device 201. The mobile device 201 may transmit a RIUM-message 226, in particular including information how to control the respective smart device 202c.

[0048] The system 300 schematically illustrated in FIG. 3 provides another embodiment during the third/fourth phase 311 including DS-TWR. Thereby, non-deferred multicast DS-TWR is also possible to achieve the same use case with less over the air communication. In particular, data may be added to the RRM and MRM air frames. When including remote control message, the MRM message might limit the possibility to add AoA back to the responder. Optionally, the controller device may indicate dedicated data transfer slot to the smart devices 302a,b,c that has been selected. Device selection may be done based on the AoA measurement during the responses. The data transfer slot may be allocated directly after the Final-message of the selected device.

[0049] The system 400 schematically illustrated in FIG. 4 illustrates communication during the second phase 410 as well as during the third and fourth phase 411. The second phase comprises a synchronization step including that the mobile device 401 sends at least one synchronization message 418 which is here configured as an RCM message. The smart device 402c receives one of the plural RCM messages 418 and synchronizes with the mobile device 201 accordingly. The second phase 410 including the synchronization step may be performed while the mobile device is in an idle mode, in particular when the phone display is turned off, such that the user may not directly input any data for controlling the smart device 401a,b,c.

[0050] When the mobile device 401 is in a non-idle mode, i.e. in particular when the display of the mobile device 401 is turned on and also pointing to the particular smart device 402c, a UWB-based DS-TWR session may be established the third and fourth phase 411. The DS- TWR session includes sending a Poll-message 419 from the mobile device 401 to the smart device 402c. The smart device 402c responds with a response message 420c. Later on, the mobile device 401 transmits a Final-message 421 and then a Final Data-message 422 which is received by the smart device 402c.

[0051] In particular, when the mobile device 401 is in display off mode, the mobile device sends (during second phase 410) a blink (418) only instead of a full DS-TWR. The blink or synchronization message 418 may be the RCM message of the multicast DS-TWR with an indicator bit that the remaining of the ranging round shall not be processed.

[0052] Only when the mobile device is activated (i.e. the display is turned on), a full ranging session is started with the smart device 402 during the phases 411, i.e. the third/fourth phase.

[0053] The system 500 schematically illustrated in FIG. 5 again illustrates communications during a first phase 509 which are similar to the communications as illustrated in FIG. 1 in phase 109. In particular, the smart device 502 may be set in an advertisement mode on the BLE layer, in particular when the boards are connected to the power supply. Thereby, the mobile device 501 is in the scan mode on the BLE layer. Once the devices 501, 502 are connected, they negotiate a common time base, for example with an accuracy smaller than 5 ms. After that, the first phase 509 is completed.

[0054] FIG. 6 schematically illustrates the system 500 in the second phase 510 which established a UWB-based time synchronization. In particular, the mobile device 501 transmits the UWB-based RCM message 518a,b,c,d for example in a regular time manner. Thereby, it is noted that the synchronization phase 510 does not perform a full DS-TWR multicast but merely sends subsequent RCM messages 518a,b,c,d. This second phase 510 may be performed while the mobile device 501 is in an idle mode, for example the display is turned off. Thereby, the mobile device sends a synchronization blink 518a,b,c,d for example each second. Whenever a blink is received by one of the smart devices, for example the smart device 502c, the “blue” LED is blinking on both devices to show that the devices still keep a synchronization on the UWB layer. After receiving/transmitting the blink (in particular the RCM messages 518a,b,c,d), both devices may enter the DPD mode again (power saving mode).

[0055] FIG. 7 illustrates the system 500 during the third/fourth phase where the mobile device starts an user interaction and a user presses for example a button. The third/fourth phase 511 comprises the third phase 525 and the fourth phase 526. The third phase 525 may be similar to the third phase 425 illustrated in FIG. 4. At the end of the third phase 525, ranging information is available, in particular the distance and the angle range in which the smart device 502c is arranged relative to the mobile device 501 is determined. During the fourth phase 426, control of the smart device 402c may be performed by the mobile device 411 and reporting information about the setting of the smart device 502c may be received by the mobile device 401. In the phases illustrated in FIG. 7, a fast reaction time (for example user feedback) is needed. The initiator is switching from the blink only to the full DS-TWR multicast ranging. Thus, the mobile device 501 performs full DS-TWR multicast in the third phase 525. Further, the block duration may be shortened to obtain a ranging periodicity of for example 200 ms. In the phase as illustrated in FIG. 7 (in particular the fourth phase 526), the mobile device 501 is monitoring the AoA of all smart devices 502a,b,c. Thereby, the mobile device may wait for user input for a given smart device 502a,b,c. In case the user input is available, the subsequent ranging will biggy-pack this data to the destination smart device 502a,b,c. The user control command for the respective smart device 502c is implemented by the RIUM-message 526. After a predetermined time duration, for example 2 s, the phases 525, 526 may automatically be terminated and the mobile device 501 may again enter the display of mode.

[0056] During UWB data transfer, collision management may be managed based on adaptive hopping scheme. A session may be unique via its ID. Session parameters may include all required settings, such as PHY settings, MAC settings and the like. When the session is started, the controllee may start sending application date via dedicated data-packets. Data transfer and ranging sessions may be built up on top of the UWB communication scheme. Thereby, the UWB communication scheme is based on a strictly time multiplexed approach to optimize power consumption. The communication scheme is organized in blocks of typical size of 50-100 ms. Thereby, blocks are segmented into rounds. In a block, the actual rounds take place where UWB communication happens. Typically for a duration of 5-10 ms, the rounds themselves are segmented into slots. The round uses slots for example of 1 ms where the actual transmission is performed.

[0057] In this specification, embodiments have been presented in terms of a selected set of details. However, a person of ordinary skill in the art would understand that many other embodiments may be practiced which include a different selected set of these details. It is intended that the following claims cover all possible embodiments.