Digital radio communication
By adjusting the periodic transmission timing under the Bluetooth™ protocol, the timing uncertainty caused by device clock drift is resolved, enabling offset adjustment between Bluetooth™ protocol transmission and other communication protocol transmissions to meet user needs or specific applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NORDIC SEMICONDUCTOR
- Filing Date
- 2021-04-01
- Publication Date
- 2026-05-12
AI Technical Summary
Under the Bluetooth™ protocol, the device’s internal clock drift causes timing uncertainty in periodic connection events, making it difficult to accurately align with periodic connection events under other communication protocols, especially when the device is communicating with external devices simultaneously via Bluetooth™.
By adjusting the periodic transmission timing under the Bluetooth™ protocol, its offset is kept within the difference between the inherent timing uncertainty and the transmission timing tolerance, ensuring that the offsets of other periodic actions conform to the protocol specifications.
It enables offset adjustment between Bluetooth™ protocol transmission and other communication protocol transmissions to meet user needs or specific applications, while maintaining protocol compliance and adapting to periodic events of different communication protocols.
Smart Images
Figure CN115669007B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to short-range, self-organizing radio communication networks. Such networks (including, for example, Bluetooth) TM It has many uses for transferring data between various different devices and controlling various different devices. Background Technology
[0002] Bluetooth TM Under this protocol, there are periodic connection events comprising specified time slots, during which the central device can send and receive data packets to / from peripheral devices. The start time of the connection event is set by the timing of the initial transmission from the central device to the peripheral device, and is specified in Bluetooth. TM This is referred to as an anchor point under the protocol.
[0003] The internal clock of the radio transceiver is not perfect and is configured for Bluetooth. TM The devices operating under this protocol will differ, having different oscillator frequencies and clock drift rates. Therefore, they are configured for Bluetooth. TM Devices operating under this protocol are required to accept Bluetooth. TM The tolerance in the timing of the specified anchor point. More specifically, Bluetooth. TM The specification stipulates that, in addition to the inherent timing uncertainty caused by its own clock drift, the device must also allow for a + / -16μS variation in the timing of connected events.
[0004] Deployed in Bluetooth TM Devices operating under this specification typically also support communication with other external devices via other means. For example, devices can be configured to communicate via wired connections (such as Ethernet, Serial Peripheral Interface (SPI), Universal Asynchronous Receiver / Transmitter (UART), etc.) and / or other wireless connections (such as Wi-Fi, 5G, LTE, etc.). Under these external connection protocols, there may be protocols very similar to Bluetooth. TM The protocol specifies those periodic connection events, and these external connection events can be shared with Bluetooth. TM Periodic connection events have the same period.
[0005] The applicant acknowledges the existence of a situation where the device is configured to operate via Bluetooth. TM It communicates with peripheral devices, and simultaneously communicates with different external devices via different communication protocols. In these cases, it might be desirable to choose Bluetooth. TM The offset between periodic connection events under a certain protocol and periodic connection events with different external devices under different communication protocols, for example, introduced from each Bluetooth... TM The wait time between connection events and each external connection event, to allow for connection events in Bluetooth. TMData received during a connection event may be transmitted via an external interface in subsequent connection events. Summary of the Invention
[0006] From a first aspect, the present invention provides a method for operating a digital radio transmitter device according to a predetermined communication protocol that defines transmission timing tolerances, the method comprising:
[0007] Multiple first periodic transmissions are sent according to the predetermined communication protocol, wherein the first periodic transmissions have a first period and an inherent timing uncertainty less than the transmission timing tolerance;
[0008] Perform multiple second-cycle actions with a second cycle, wherein the first cycle and the second cycle are equal to or integer multiples of each other;
[0009] The timing of one or more of the first periodic transmissions is adjusted by an amount greater than the inherent timing uncertainty but less than or equal to the difference between the inherent timing uncertainty and the transmission timing tolerance, so as to temporarily change the first period by an amount less than or equal to the transmission timing tolerance, thereby changing the offset between the first transmission and the second action.
[0010] The present invention extends to a computer-readable medium comprising instructions configured to cause a digital radio transmitter device to operate in accordance with the method described above.
[0011] The invention also extends to a digital radio transmitter device configured to operate according to a predetermined communication protocol defining transmission timing tolerances, wherein the device is configured to:
[0012] Multiple first periodic transmissions are sent according to the predetermined communication protocol, wherein the first periodic transmissions have a first period and an inherent timing uncertainty less than the transmission timing tolerance;
[0013] Perform multiple second-cycle actions with a second cycle, wherein the first cycle and the second cycle are equal to or integer multiples of each other;
[0014] The timing of one or more of the first periodic transmissions is adjusted by an amount greater than the inherent timing uncertainty but less than or equal to the difference between the inherent timing uncertainty and the transmission timing tolerance, so as to temporarily change the first period by an amount less than or equal to the transmission timing tolerance, thereby changing the offset between the first transmission and the second action.
[0015] Therefore, those skilled in the art will see that, according to the present invention, the offset between periodic digital radio protocol transmissions and other periodic actions can be adjusted to suit user needs or specific applications by utilizing the difference between the lower actual transmission uncertainty achievable by the device and the tolerances allowed in the protocol specification. By introducing such an intentional change in the timing of the protocol transmission, the offset between the protocol transmission and a second periodic action not normally specified according to the protocol can be altered while maintaining protocol compliance.
[0016] The offset between the first and second periodic transmissions can change by increasing or decreasing. The offset can initially be zero, or it can be adjusted to zero. For example, a user might want to reduce the latency between the first and second periodic actions. Alternatively, a user might want to adjust the offset between the first and second periodic actions to a specific, known value. Of course, the offset can also change from one non-zero value to another.
[0017] Although one cycle can be an integer multiple of another cycle, in one set of implementations, the first and second cycles are equal.
[0018] The timing of more than one of the first periodic transmissions can be adjusted to obtain an offset between the first transmission and the second action. This offset is greater than the difference between the inherent timing uncertainty and the transmission timing tolerance, i.e., greater than the offset that could be obtained by adjusting the timing of only one of the first periodic transmissions. In other words, the timing of more than one of the first periodic transmissions can be adjusted to gradually build up any desired offset, which may therefore result in a relatively large offset. In the case of adjusting more than one of the first periodic transmissions, these first periodic transmissions can be continuous. This allows for the gradual application of changes in the offset.
[0019] In one set of implementations, the first predetermined communication protocol is with Bluetooth. TM Protocol-compatible protocols, such as Bluetooth TM Low power consumption. In one set of implementations, the second periodic action is triggered by an event in another subsystem of the device. For example, the second periodic action may include sending or receiving signals according to another radio protocol such as LTE, WiFi, Zigbee, etc., or a proprietary radio protocol or wired communication protocol such as SPI or UART. In a particular example, the second periodic action includes receiving a synchronization signal from a sensor via SPI.
[0020] In one set of implementations, the first periodic transmission includes the initial transmission of periodic connection events according to a predetermined communication protocol. Such connection events may include designated time slots for sending and receiving data packets between the central device and connected peripheral devices. The start time of each connection event may be determined by the timing of the previous connection event.
[0021] In one set of implementations, the transmission timing tolerance specified in the protocol is + / - 16 μS. This means that, in addition to inherent timing uncertainties (e.g., caused by clock drift), the total timing uncertainty on the transmitting side will be 16 μS. On the receiver side, the total uncertainty will further depend on the receiver's inherent timing uncertainty or clock drift.
[0022] In one set of implementations, the inherent timing uncertainty that the device can achieve is between 1 μS and 10 μS, for example, between 2 μS and 8 μS. Attached Figure Description
[0023] Embodiments of the invention will now be described with reference to the accompanying drawings, in which:
[0024] Figure 1 This is a schematic diagram illustrating a typical radio communication system;
[0025] Figure 2 It shows Bluetooth. TM A schematic diagram of low energy emission (BLE) anchor points and related timing tolerances;
[0026] Figure 3 This is a schematic diagram illustrating the comparison between BLE tolerance and actual timing uncertainty;
[0027] Figure 4a and Figure 4b This is a schematic diagram illustrating how the timing of periodic connection events is adjusted over several cycles according to the present invention;
[0028] Figure 5 This shows how periodic Bluetooth can be adjusted. TM A schematic diagram of the offset between the connection event and a periodic external event with the same nominal period; and
[0029] Figure 6 It is similar to Figure 5 The diagram illustrates that the period of external events is Bluetooth. TM Twice the period of the connection event. Detailed Implementation
[0030] Figure 1 A radio system is shown, the radio system including Bluetooth Low Energy... TMThe central radio transceiver device 10, also based on Bluetooth Low Energy, is operated. TM The system includes an operating peripheral radio transceiver device 12 and an external device 13. Hereinafter, these will be referred to as central device 10, peripheral device 12, and external device 13. Central device 10 includes an antenna 14, and peripheral device 12 includes an antenna 18. Central device 10 and external device 13 are coupled via an external connection 16. External connection 16 may include a wireless connection (e.g., WiFi) or a wired connection (e.g., Ethernet, serial bus, etc.), and data can be transmitted from central device 10 to external device 13 and / or from external device 13 to central device 10. External devices may include any device capable of communicating via external connection 16, such as a router, server, computer, tablet, smartphone, etc.
[0031] Those skilled in the art will also readily understand that many standard modules, such as processors, oscillators, filters, amplifiers, digital-to-analog converters (DACs), and analog-to-digital converters (ADCs), are provided in radio transceivers 10 and 12, but for the sake of brevity, descriptions of these modules are omitted.
[0032] Figure 1 Bluetooth Low Energy was also demonstrated. TM The radio signal paths are 20 and 22. Signal path 20 runs from a central device 10, which acts as a transmitter via its antenna 14, to a peripheral device 12, which acts as a receiver via its antenna 18. Signal path 22 runs from a peripheral device 12, which acts as a transmitter via its antenna 18, to a central device 10, which acts as a receiver via its antenna 14.
[0033] Figure 2 It shows the Bluetooth Low Energy... TM The (BLE) specification defines nominal anchor points 24, 25, and 26 for periodic connection events 31, 32, and 33 of duration 29 for central device 10, and their associated timing tolerances 30. Nominal anchor points 24, 25, and 26 occur periodically and specify the nominal start time of connection events 31, 32, and 33. Figure 2 The nominal period 39 is shown between anchor points 24, 25 and 26.
[0034] The duration of connection event 29 is less than the period 39 between anchor points, and it will be understood that the duration 29 of each connection event 31, 32, and 33 need not be the same; each event may have a different duration, as long as the duration is less than the period 39. Connection events may include any combination of signal transmission from central device 10 to peripheral device 12 and signal reception from peripheral device 12 to central device 10.
[0035] like Figure 2As shown, the BLE specification allows the actual start times of the corresponding connection events 31, 32, and 33 (t) to be determined by using timing tolerance 30. 开始 Small deviations from the corresponding nominal anchor points 24, 25, and 26, while still maintaining compliance with specifications. The start times of connection events 35, 36, and 37 are subject to the maximum permissible deviation (TOL) from the corresponding nominal anchor points 24, 25, and 26. max The following formula is given:
[0036] TOL max =±(16μs+drift) 时钟 (1)
[0037] Among them drift 时钟 It is the drift of the internal clock of the central device 10.
[0038] Therefore, the actual start times 35, 36, and 37 of connection events 31, 32, and 33 are allowed to be anywhere within the following range:
[0039] t 锚 -|TOL max |≤t 开始 ≤t 锚 +|TOL max |, (2)
[0040] Where t 锚 It is the time of the corresponding anchor point 24, 25, or 26 for each connection event 31, 32, or 33.
[0041] When the start time of connection events 31, 32, or 33 deviates from the nominal anchor point 24, 25, or 26 within the allowable range, a new anchor point is defined as the actual start time of the connection event. The start time of the first connection event 31 is the same as the nominal anchor point 24, therefore no new anchor point is defined. However, the second connection event 32 is slightly delayed, so its start time 36 deviates from the nominal anchor point 25. The central device 10 and the peripheral device 12 therefore consider the start time 36 of the second connection event 32 as the new anchor point 34. Therefore, the new anchor point 34 is offset by an amount 23 from the nominal anchor point 25. The timing of the next nominal anchor point 26 is based on this new anchor point 34. In other words, the next nominal anchor point 26 is separated from the new anchor point 34 by a nominal period 39.
[0042] However, the third connection event 33 is slightly advanced, causing its start time 37 to deviate from the nominal anchor point 26. This again provides a new anchor point 38 at the start time 37 of the third connection event 33. Therefore, the new anchor point 38 is offset 28 away from the nominal anchor point 26. It should be understood that subsequent nominal anchor points ( Figure 2 The timing (not shown) will be based on a new anchor point 38 with a nominal period of 39, unless any other intentional offset is applied.
[0043] Figure 3 This illustrates the actual uncertainty 40 (TOL) in the start time 35 of the connection event 31 of anchor point 24 according to the BLE specification, where tolerance 30 is equal to duration 29. 实际 A comparison between them can be made by providing a comparison with Bluetooth. TM The specification requires specific transmission hardware to implement better timing drift and jitter. In this example, the implementation used allows for guaranteeing the start time of connection events with higher precision than the BLE specification tolerance of 30, resulting in TOL. 实际 <TOL max .
[0044] Therefore, the actual start time of 35 can be intentionally adjusted to fall within the maximum adjustment range of 42 (ADJ). max Any position within ) while still satisfying the BLE specification. The maximum adjustment range of 42 is given by the following formula:
[0045] ADJ max =±(TOL) max -TOL 实际 (3)
[0046] Therefore, the connection event 31 with actual uncertainty 40 can be selected as having an actual start time at any position within the following range:
[0047] t 锚 -|ADJ max |≤t 开始 ≤t 锚 +|ADJ max |, (4)
[0048] It still meets the BLE specification.
[0049] Figure 4a and Figure 4b The diagram illustrates how the corresponding start times 35, 36, 37, and 38 of the periodic connection events 31, 32, 33, and 34 of duration 29 can be adjusted within the aforementioned maximum adjustment range 42 to achieve the desired offset 44 by adjusting the nominal anchor points 24a, 25a, 26a, and 27a. For comparison, markers 80, 81, 82, and 83, separated by the nominal period 39, show the position of the anchor points without adjustment. In this example, the desired offset 44 between connection events 31, 32, 33, and 34 and comparison markers 80, 81, 82, and 83 is equal to +ADJ. max .
[0050] Figure 4aAn example is shown where the desired offset 44 is reached within a single cycle. The start time 35a of connection event 31a is equal to the time of its nominal anchor 24a. The start time 36a of the subsequent connection event 32a is intentionally delayed by a delay time (t). 延迟 46a, the delay time has the same value as the desired offset 44. Therefore, the start time 36a of connection event 32a is offset from its anchor point 25a by the desired offset 44. The anchor point is then reset to a new point 85a for subsequent events. The start times 37a and 38a of subsequent connection events 33a and 34a are not intentionally further delayed, meaning that the subsequent connection events are transmitted according to their respective anchor points 26a and 27a, but remain offset from their original anchor points 82 and 83 by the desired offset 44.
[0051] Figure 4b An example is shown where the desired offset 44 is reached within three cycles. The start time 35b of connection event 31b is equal to the time of anchor point 24b. The start time 36b of the subsequent connection event 32b is intentionally delayed by a delay of 46b, the value of which is 1 / 3 of the desired offset 44. This defines a new anchor point 85b for central device 10 and peripheral device 12, meaning that the start time 36b of connection event 32b is delayed by an amount of 46b relative to the original time of anchor point 81.
[0052] The nominal anchor 26b of the next connection event 33b starts from the new anchor 85b after the nominal period 39, but the start time 37b of this connection event 32b is then further delayed by the same delay time 46b, giving a modified anchor 86b again and delaying the start time 37b from the original anchor 82 by twice the amount of this delay 99.
[0053] Finally, the start time 38b of the last connection event 34b is then further delayed by the same delay time 46b from the nominal anchor point 27b to create another new anchor point 87b, which sets the nominal period starting from the previous anchor point 86b. This results in the total offset between the start time 38b of the last connection event 34b and the original anchor point 83 being equal to OFF. des OFF des This is the expected offset value of 44. Subsequent connection events (not shown) will not be further delayed, meaning they will occur based on their respective anchors, according to the nominal period 39 and the last reset anchor point 87b.
[0054] Those skilled in the art will understand that the number of cycles that can achieve the desired offset is not limited to three, but can be any number. Furthermore, the time delays added to each connection event need not be equal as in this example: the individual time delays may differ. Those skilled in the art will also understand that the offset between the start time of a connection event and its nominal anchor point can be negative; that is, the start time of a connection event can be advanced, such that the connection event occurs before its nominal anchor point.
[0055] Delaying the start time of a connection event can be considered equivalent to temporarily reducing the frequency of the connection event for several cycles and then returning to the original frequency. The result is that the phase of the connection events is delayed relative to their original phase. Similarly, advancing the start time of a connection event can be considered equivalent to temporarily increasing the frequency of the connection event for several cycles and then returning to the original frequency. The result is that the phase of the connection events is advanced relative to their original phase.
[0056] Figure 5 This illustrates how an offset can be added between the start time of BLE connection events and their respective nominal anchor points to adjust the offset between the BLE connection events and other periodic events in central device 10. In this example, the other periodic events include external connection events 55, 56, 57, and 58 via external connection 16 to external device 13. In this example, external connection events 55, 56, 57, and 58, as well as BLE connection events 31, 32, 33, and 34, have the same nominal period 39, and the durations 29 and 62 of the BLE connection events and external connection events are respectively less than period 39.
[0057] In this example, a wait time of 69 is expected from the start times 50, 51, 52, and 53 of periodic external communication events 55, 56, 57, and 58 to the start times 35, 36, 37, and 38 of periodic BLE connection events 31, 32, 33, and 34, for example, to avoid processor latency or mutual RF interference.
[0058] In this example, firstly, the start time of the periodic external connection event is slightly later than the anchor point of the BLE connection event. This is indicated by offset 60: the start time 35 of BLE connection event 31 (which is the same as the nominal anchor point 24 of the BLE connection event) precedes the start time 50 of external connection event 55. Assuming that the start time of the BLE connection event is actually expected to be after the start time of the external connection event, the start time 36 of the next BLE connection event 32 is delayed by a delay of 46. Therefore, although the nominal anchor point 25 of BLE connection event 32 remains before the start time 51 of external connection event 56, the start time 36 of BLE connection event 32 is offset by offset 61 from the start time 51 of external event 56.
[0059] The start time 37 of the subsequent BLE connection event 33 is also delayed by the same delay time 46. Therefore, although the nominal anchor 26 of BLE connection event 33 is already after the start time 52 of the external connection event 57, the start time 37 of BLE connection event 33 is further delayed from the start time 52 of the external event 57 to give the desired wait time 69 and define a new nominal anchor 86. By adjusting the start times of multiple BLE connection events (two consecutive connection events 32 and 33 in this example), the offset 69 obtained between BLE connection event 33 and external event 57 (and subsequent BLE connection events and external events) is greater than the difference 42 between the inherent timing uncertainty 30 and the transmission timing tolerance 40 (i.e., the offset 69 is greater than the maximum amount that the start time of a single BLE connection event can be adjusted). Therefore, by adjusting the start time of multiple BLE connection events (each of which may be consecutive or discontinuous), the central device 10 is able to adjust the offset between the BLE connection events and external events to any desired value, particularly to a value greater than the offset that could be obtained by adjusting the timing of only one BLE connection event.
[0060] The start time 38 of the final BLE connection event 34 was not intentionally further delayed, meaning its nominal anchor 27 is separated from the previous new anchor 86 by a nominal period 39. Therefore, the start time of subsequent BLE connection events continues to be offset from the start time of the external connection event by the expected waiting time 69. Those skilled in the art will understand that this method can be used to adjust the offset between periodic BLE connection events and other periodic events (with the same period) to the desired value while still satisfying the BLE specification. It will also be understood that if the desired offset is within the maximum permissible adjustment range of the anchor, the desired offset can be achieved within a single period, but if… Figure 4b As shown, larger offsets can be achieved over any number of periods.
[0061] Figure 6Another example is shown where adding an offset between the start time of BLE connection events and their nominal anchor point can be used to adjust the offset between BLE connection events and other periodic events in central device 10. In this example, other periodic events include external connection events 64 and 65 via external connection 16 to external device 13. In this example, external connection events 64, 65 and BLE connection events 31, 32, 33, and 34 have different periods, where the period 72 of the external connection event is twice the period of BLE connection event 39. The durations 29 and 70 of the BLE connection events and external connection events are respectively less than the periods 39 and 72 of the BLE connection events and external connection events. The ratio of period 72 to period 39 is not limited to two in this example, but can be any integer (therefore, period 72 is a multiple of period 39). Alternatively, the period of the BLE connection event can be an integer multiple of the period of the external event.
[0062] In this example, a shorter wait time 76 is expected from the start times 66 and 67 of periodic external communication events 64 and 65 to the start times 35 and 37 of periodic BLE connection events 31 and 33.
[0063] Similarly, the start time of periodic external connection events is slightly later than the nominal anchor point of the BLE connection event. This is indicated by offset 74: the start time 35 of the first BLE connection event 31 (which is the same as the nominal anchor point 24) precedes the start time 66 of the first external connection event 64. It is expected that the start time of every other BLE connection event will be after the start time of the most recent external connection event. To achieve this, the start time 36 of the next BLE connection event 32 is delayed by a delay of 46. This sets a new anchor point 85 at the start time 36 of the next BLE connection event 32. The timing of the subsequent nominal anchor point 26 is separated from the newly set anchor point 85 by one period 39. Therefore, the start time 37 of the subsequent BLE connection event 33 is separated from the start time 67 of the corresponding external connection event 65 by the expected waiting time 76.
[0064] Those skilled in the art will understand that the examples given above are not limiting, and many modifications and variations are possible within the scope of this invention.
Claims
1. A method for operating a digital radio transmitter device according to a predetermined communication protocol that defines transmission timing tolerances, the method comprising: Multiple first periodic transmissions are sent according to the predetermined communication protocol, wherein the first periodic transmissions have a first period and an inherent timing uncertainty less than the transmission timing tolerance; Perform multiple second-cycle actions with a second cycle, wherein the first cycle and the second cycle are equal to or integer multiples of each other; The timing adjustment of one or more of the first periodic transmissions in the first periodic transmissions is greater than the inherent timing uncertainty but less than or equal to the difference between the inherent timing uncertainty and the transmission timing tolerance by an amount that temporarily changes the first period by an amount that is less than or equal to the transmission timing tolerance, thereby changing the offset between the first periodic transmission and the second periodic action. as well as The timing of more than one of the first periodic transmissions in the first periodic transmission is adjusted to obtain an offset between the first periodic transmission and the second periodic action, the offset being greater than the difference between the inherent timing uncertainty and the transmission timing tolerance.
2. The method of claim 1, wherein each first periodic transmission includes an initial transmission of a periodic connection event, each connection event including a designated time slot for sending and receiving data packets between a central device and a connected peripheral device in accordance with a predetermined radio communication protocol.
3. The method of claim 2, wherein the timing of each connection event is determined by the timing of the previous connection event.
4. The method according to any one of claims 1 to 3, wherein the adjusted more than one first periodic transmission is continuous.
5. The method according to any one of claims 1 to 3, wherein the predetermined communication protocol is Bluetooth. TM Low energy consumption.
6. The method according to any one of claims 1 to 3, wherein the inherent timing uncertainty achievable by the device is between 1 µS and 8 µS.
7. The method according to any one of claims 1 to 3, wherein each of the first periodic transmissions in the first periodic transmissions is triggered by a first subsystem of the device, and each of the second periodic actions in the second periodic actions is triggered by a second subsystem of the device.
8. The method according to any one of claims 1 to 3, wherein each of the second periodic actions comprises transmitting or receiving signals according to another predetermined radio communication protocol.
9. The method according to any one of claims 1 to 3, wherein each of the second periodic actions comprises sending or receiving signals according to a predetermined wired communication protocol.
10. A non-transitory computer-readable medium comprising instructions configured to cause a digital radio transmitter device to operate in accordance with the method as described in any of the preceding claims.
11. A digital radio transmitter device configured to operate according to a predetermined communication protocol defining transmission timing tolerances, wherein the device is configured to: Multiple first periodic transmissions are sent according to the predetermined communication protocol, wherein the first periodic transmissions have a first period and an inherent timing uncertainty less than the transmission timing tolerance; Perform multiple second-cycle actions with a second cycle, wherein the first cycle and the second cycle are equal to or integer multiples of each other; The timing adjustment of one or more of the first periodic transmissions in the first periodic transmissions is greater than the inherent timing uncertainty but less than or equal to the difference between the inherent timing uncertainty and the transmission timing tolerance by an amount that temporarily changes the first period by an amount that is less than or equal to the transmission timing tolerance, thereby changing the offset between the first periodic transmission and the second periodic action. as well as The timing of more than one of the first periodic transmissions in the first periodic transmission is adjusted to obtain an offset between the first periodic transmission and the second periodic action, the offset being greater than the difference between the inherent timing uncertainty and the transmission timing tolerance.
12. The device of claim 11, wherein the inherent timing uncertainty achievable by the device is between 1 µS and 10 µS.
13. The device according to claim 11 or 12, wherein each of the first periodic transmissions in the first periodic transmissions is triggered by a first subsystem of the device, and each of the second periodic actions in the second periodic actions is triggered by a second subsystem of the device.