Microwave sensing device and method for avoiding transmission collision in unlicensed frequency band

Abstract

The invention relates to a microwave sensing device and method for avoiding transmission collision in an unlicensed frequency band. A microwave sensing device includes a generating circuit configured to generate a microwave sensing packet according to a wireless communication protocol; the detection circuit is used for detecting whether a channel is idle; a transmitting circuit, coupled to the generating circuit and the detecting circuit, for transmitting the microwave sensing packet in response to the channel being idle; a receiving circuit, coupled to the detection circuit, for receiving a received microwave sensing packet corresponding to the microwave sensing packet; and a processing circuit, coupled to the receiving circuit, for determining whether the received microwave sensing packet contains an interference.

Description

TECHNICAL FIELD

[0001] The present application relates to a microwave sensing device and method for a wireless communication system, and more particularly to a microwave sensing device and method for avoiding transmission collision in an unlicensed band. BACKGROUND

[0002] The microwave sensing device usually operates in an unlicensed band. In the unlicensed band, there are other communication devices of wireless communication systems. When the microwave sensing device and the communication devices use the same frequency band and are close in physical location, transmission collision occurs, so that the microwave sensing device and the communication devices cannot identify signals. In the prior art, a dynamic frequency selection mechanism defines that the priority of the microwave sensing device is higher than that of the communication device to avoid transmission collision. However, the frequency at which the microwave sensing device transmits signals is low and the duration of transmitting signals is short, resulting in low utilization of the unlicensed band. Therefore, how to effectively use the unlicensed band and avoid transmission collision is a problem to be solved. SUMMARY

[0003] One of the purposes of the present application is to provide a microwave sensing device and method for avoiding transmission collision in an unlicensed band to solve the above problems.

[0004] An embodiment of the present application discloses a microwave sensing device, comprising a generating circuit configured to generate a microwave sensing packet according to a wireless communication protocol; a detecting circuit configured to detect whether a channel is idle; a transmitting circuit coupled to the generating circuit and the detecting circuit, and configured to transmit the microwave sensing packet in response to the channel being idle; a receiving circuit coupled to the detecting circuit, and configured to receive a received microwave sensing packet corresponding to the microwave sensing packet; and a processing circuit coupled to the receiving circuit, and configured to determine whether the received microwave sensing packet contains an interference.

[0005] The present application also discloses a method for avoiding transmission collision in an unlicensed band. The method comprises generating a microwave sensing packet according to a wireless communication protocol; detecting whether a channel is idle; transmitting the microwave sensing packet to respond to the idle channel; receiving a received microwave sensing packet corresponding to the microwave sensing packet; and determining whether the received microwave sensing packet contains an interference.

[0006] In summary, the present application provides a microwave sensing device and method for avoiding transmission collision in an unlicensed band. The microwave sensing device generates and transmits a microwave sensing packet according to a wireless communication protocol. After receiving the microwave sensing packet, the communication device uses the envelope of the microwave sensing packet to obtain the packet information (e.g. the length of the microwave sensing packet) of the microwave sensing packet according to the wireless communication protocol. According to the packet information, the communication device does not perform data transmission during the packet transmission. Therefore, the microwave sensing device does not collide with the communication device when transmitting the microwave sensing packet. BRIEF DESCRIPTION OF DRAWINGS

[0007] Figure 1 A schematic diagram of a microwave sensing device according to an embodiment of the present application.

[0008] Figure 2 A schematic diagram of a microwave sensing packet according to an embodiment of the present application.

[0009] Figure 3 A schematic diagram of a microwave sensing packet according to an embodiment of the present application.

[0010] Figure 4 A flowchart of a flow according to an embodiment of the present application.

[0011] LIST OF SYMBOLS

[0012] 10: microwave sensing device

[0013] 100: generating circuit

[0014] 110: detecting circuit

[0015] 120: transmitting circuit

[0016] 130: receiving circuit

[0017] 140: processing circuit

[0018] 20, 30: microwave sensing packet

[0019] WP: envelope

[0020] SG: single frequency signal

[0021] PB: preamble

[0022] PHY HD: physical layer header

[0023] MAC HD: media access control layer header

[0024] 40: flow

[0025] S400, S402, S404, S406, S408, S410, S412: step DETAILED DESCRIPTION

[0026] Figure 1 A schematic diagram of a microwave sensing device 10 according to an embodiment of the present application. The microwave sensing device 10 can operate in an unlicensed band (e.g., but not limited to 2.4G or 5.8G) and is an electronic device that uses microwave radiation to sense motion, presence, or distance. The microwave sensing device 10 can be widely used in various applications, such as, but not limited to, weather measurement, military use, security system, traffic management, non-contact switch, lighting control, and parking sensor, etc. In Figure 1 In an embodiment, the microwave sensing device 10 includes a generating circuit 100, a detecting circuit 110, a transmitting circuit 120, a receiving circuit 130, and a processing circuit 140. In detail, the generating circuit 100 is configured to generate a microwave sensing packet according to a wireless communication protocol. The detecting circuit 110 is configured to detect whether a channel is idle. The transmitting circuit 120 is coupled to the generating circuit 100 and the detecting circuit 110 and is configured to transmit the microwave sensing packet in response to the channel being idle. The receiving circuit 130 is coupled to the detecting circuit 110 and is configured to receive a received microwave sensing packet corresponding to the transmitted microwave sensing packet. In an embodiment, the transmitted microwave sensing packet is reflected by an object to generate the received microwave sensing packet after the transmitting circuit 120 transmits the microwave sensing packet. The processing circuit 140 is coupled to the receiving circuit 130 and is configured to determine whether the received microwave sensing packet includes interference.

[0027] In an embodiment, the wireless communication protocol includes a communication protocol of a local area network (LAN) (e.g., WiFi), a communication protocol of a personal area network (PAN) (e.g., Bluetooth), or a ZigBee protocol, but is not limited thereto. In an embodiment, the detecting circuit continues to detect whether the channel is idle in response to the channel not being idle. In an embodiment, the transmitting circuit does not transmit the microwave sensing packet in response to the channel not being idle.

[0028] In one embodiment, the microwave sensing package includes a wrapper and a single-tone signal. In one embodiment, the contents of the wrapper are fixed. That is, the wrapper can be pre-generated (e.g., by hardware or software). In one embodiment, the single-tone signal includes, but is not limited to, a continuous wave (CW) or a frequency modulated continuous wave (FMCW).

[0029] In one embodiment, the envelope includes a preamble and a physical (PHY) layer header. Figure 2 .exist Figure 2 In the embodiment, the microwave sensing packet 20 includes a wrapper WP and a single frequency signal SG. The wrapper WP includes a preamble PB and a physical layer header PHY_HD. In one embodiment, the physical layer header indicates the length of the single frequency signal.

[0030] In one embodiment, the envelope includes a preamble, a physical layer header, and a medium access control (MAC) layer header. Figure 3 .exist Figure 3 In the embodiment, the microwave sensing packet 30 includes a wrapper WP and a single-frequency signal SG. The wrapper WP includes a preamble PB, a physical layer header PHY_HD, and a media access control layer header MAC_HD. In one embodiment, the physical layer header indicates the combined length of the media access control layer header and the single-frequency signal (i.e., the length of the physical layer payload), and the media access control layer header indicates the length of the single-frequency signal.

[0031] In one embodiment, the transmitting circuit 120 transmits at least one packet to a communication device utilizing a wireless communication protocol. In one embodiment, the at least one packet is used to announce channel occupation. In other words, based on the at least one packet, the communication device learns that the microwave sensing device 10 is occupying the channel (e.g., the duration of the channel being occupied by the microwave sensing device 10). In one embodiment, the at least one packet includes a request to send packet and / or a confirmation to send packet, but is not limited thereto.

[0032] In an embodiment, the operation of the detection circuit 110 to detect whether the channel is idle includes: generating a local sequence according to the preamble; matching the local sequence with a received signal received in the channel to generate a matching result; determining that the channel is not idle in response to the matching result being greater than (or not less than) a first threshold; and determining that the channel is idle in response to the matching result being not greater than (or less than) the first threshold. In an embodiment, the received signal is received by the receiving circuit 130.

[0033] In an embodiment, the operation of the detection circuit 110 to detect whether the channel is idle includes: calculating (or detecting) a power of a received signal received in the channel; determining that the channel is not idle in response to the power being greater than (or not less than) a second threshold; and determining that the channel is idle in response to the power being not greater than (or less than) the second threshold. In an embodiment, the received signal is received by the receiving circuit 130.

[0034] In an embodiment, the processing circuit 140 discards the received microwave sensing packet in response to the received microwave sensing packet including interference. In an embodiment, after the processing circuit 140 discards the received microwave sensing packet, the transmitting circuit 120 retransmits the microwave sensing packet in the case that the channel is idle. In an embodiment, the operation of the processing circuit 140 to determine whether the received microwave sensing packet includes interference includes: calculating (or detecting) a signal power out of band; determining that the received microwave sensing packet includes interference in response to the signal power being greater than (or not less than) a third threshold; and determining that the received microwave sensing packet does not include interference in response to the signal power being not greater than (or less than) the third threshold. For example, assuming that a sampling frequency Fs of an analog-to-digital converter (ADC) (not labeled in the figures) of the microwave sensing device 10 is greater than an effective bandwidth Fcof the microwave sensing packet, the processing circuit 140 can calculate (or detect) a signal power between a frequency band Figure 1 and a frequency band . If the signal power is greater than (or not less than) the third threshold, the processing circuit 140 determines that the received microwave sensing packet includes interference and discards the received microwave sensing packet. If the signal power is not greater than (or less than) the third threshold, the processing circuit 140 determines that the received microwave sensing packet does not include interference and continues to process the received microwave sensing packet. The aforementioned operation of the microwave sensing device 10 can be summarized as a flow 40 of

[0035] . The flow 40 includes the following steps: Figure 4

[0036] Step S400: Start. ​

[0037] Step S402: generating a microwave sensing packet according to a wireless communication protocol.

[0038] Step S404: detecting whether a channel is idle.

[0039] Step S406: transmitting the microwave sensing packet to respond that the channel is idle.

[0040] Step S408: receiving a received microwave sensing packet corresponding to the microwave sensing packet.

[0041] Step S410: determining whether the received microwave sensing packet contains an interference.

[0042] Step S412: ending.

[0043] Flow 40 is used to illustrate the operation of microwave sensing device 10, respectively. Detailed description and variations can refer to the foregoing, and will not be repeated here.

[0044] It should be noted that the implementation of microwave sensing device 10 (and the generation circuit 100, detection circuit 110, transmission circuit 120, receiving circuit 130 and processing circuit 140 therein) can be in many ways. For example, the above-mentioned devices (circuits) can be integrated into one or more devices (circuits). In addition, microwave sensing device 10 can be implemented in hardware (such as circuit), software, firmware (combination of hardware device and computer instructions and data, and computer instructions and data belong to read-only software on hardware device), electronic system, or combination of the above devices, not limited thereto.

[0045] The term "preamble" used in the above description can be replaced with "training field". The term "determining" used in the above operation can be replaced with "computing", "calculating", "obtaining", "generating", "outputting", "using", "choosing / selecting", "deciding", or "being configured to". The term "detecting" used in the above operation can be replaced with "monitoring", "receiving", "sensing", or "obtaining". The term "according to" used in the above operation can be replaced with "in response to". The term "corresponding to" used in the above description can be replaced with "of" or "associated with". The term "via" used in the above description can be replaced with "on", "in", or "at". The term "when" used in the above description can be replaced with "in response to".

[0046] In summary, the present application provides a microwave sensing device and method for avoiding transmission collision in unlicensed frequency band. According to a wireless communication protocol, the microwave sensing device generates and transmits a microwave sensing packet. After receiving the microwave sensing packet, a communication device using the wireless communication protocol obtains packet information (e.g. length of the microwave sensing packet) of the microwave sensing packet according to the envelope of the microwave sensing packet. According to the packet information, the communication device does not perform data transmission during packet transmission. Therefore, when transmitting the microwave sensing packet, the microwave sensing device does not collide with the communication device.

[0047] The above description is only the preferred embodiment of the present application, and any equivalent changes and modifications made according to the claims of the present application shall be within the scope of the present application.

Claims

1. A microwave sensing device comprising: a generating circuit for generating a microwave sensing packet according to a wireless communication protocol; a detection circuit for detecting whether a channel is idle; a transmitting circuit coupled to the generating circuit and the detecting circuit, for transmitting the microwave sensing packet in response to the channel being idle; a receiving circuit coupled to the detecting circuit, configured to receive a received microwave sensing packet corresponding to the microwave sensing packet; as well as A processing circuit is coupled to the receiving circuit and is used to determine whether the received microwave sensing packet contains an interference. 2 . The microwave sensing device as claimed in claim 1 , wherein the detection circuit continues to detect whether the channel is idle in response to the channel not being idle. 3 . The microwave sensing device as claimed in claim 1 , wherein the transmitting circuit does not transmit the microwave sensing packet in response to the channel being not idle. 4 . The microwave sensing device as claimed in claim 1 , wherein the microwave sensing package comprises an envelope and a single-frequency signal. The microwave sensing device as claimed in claim 4 , wherein the envelope comprises a preamble and a physical layer header. The microwave sensing device as claimed in claim 5 , wherein the physical layer header indicates a length of the single frequency signal. 7 . The microwave sensing device as claimed in claim 4 , wherein the envelope comprises a preamble, a physical layer header, and a media access control layer header. 8 . The microwave sensing device as claimed in claim 7 , wherein the physical layer header indicates a sum of the lengths of the media access control layer header and the single frequency signal, and the media access control layer header indicates a length of the single frequency signal. 9 . The microwave sensing device as claimed in claim 1 , wherein the processing circuit discards the received microwave sensing packet in response to the received microwave sensing packet containing the interference.

10. A method for avoiding transmission collisions in an unlicensed frequency band, comprising: generating a microwave sensing packet according to a wireless communication protocol; Detect whether a channel is idle; sending the microwave sensing packet in response to the channel being idle; receiving a received microwave sensing packet corresponding to the microwave sensing packet; as well as Determining whether the received microwave sensing packet contains an interference.

Images