Feature embedding method and system based on single-antenna cyclic delay diversity

Abstract

The invention provides a feature embedding method and system based on single-antenna cyclic delay diversity, and the method comprises the following steps: carrying out the cyclic delay of different cyclic delay amounts for the signals of different users at a transmitting end, so as to obtain corresponding cyclic delay signals, aliasing the signal of each user and the corresponding cyclic delay signal, and transmitting the obtained aliasing signal through a single antenna; and at a receiving end, the cyclic delay amount of each user is acquired based on the aliasing signal, and the corresponding user is identified based on the cyclic delay amount. According to the feature embedding method and system based on single-antenna cyclic delay diversity, the application of spectrum sensing based on feature detection is expanded to single-antenna equipment, and a new solution is provided for feature embedding of an Internet of Things terminal.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communications, and in particular to a feature embedding method and system based on single-antenna cyclic delay diversity. Background Art

[0002] With the freezing of 3GPP R18, mobile communication systems are accelerating from 5G-Advanced to 6G. 6G networks will face ubiquitous access to multiple types of intelligent communication terminals and massive demands for heterogeneous service data, resulting in increasingly scarce spectrum resources. On the one hand, this guides the communication system to evolve to higher frequency bands to obtain larger communication bandwidth, and on the other hand, it also puts forward new requirements for improving the utilization of spectrum resources.

[0003] The cognitive radio network based on dynamic spectrum hole discovery and opportunistic spectrum access can further improve the utilization of spectrum resources without affecting the transmission rate of the primary user through the dynamic occupation of spectrum resources by primary and secondary users. The premise of realizing opportunistic access of secondary users is that secondary users can perform efficient spectrum perception. The core of this technology is to make timely and accurate judgments on the transmission status of the primary user, that is, the idle or occupied status of the spectrum resources. On the one hand, it is necessary to improve the detection probability to avoid interference of secondary users on the transmission of the primary user, and on the other hand, it is necessary to reduce the false alarm probability to avoid idle spectrum resources.

[0004] Typical spectrum sensing technologies include the following:

[0005] (1) Signal energy detection

[0006] Signal energy detection compares the received signal energy with a preset threshold to determine whether there is signal transmission. This detection method does not require prior information about the primary user signal and is simple to implement, but the detection performance is easily affected by noise uncertainty and performance degrades in low signal-to-noise ratio environments.

[0007] (2) Matched filter detection

[0008] Matched filter detection is that the secondary user matches the detection signal with the primary user signal in the database. This technology has strong robustness in the additive white Gaussian noise channel, but requires the secondary user to have prior information about the primary user's signal, and the implementation complexity is relatively high.

[0009] (3) Signal feature detection

[0010] Signal feature detection uses the cyclostationary characteristics of the received signal to identify artificial communication signals, thereby assisting users in achieving opportunistic access to spectrum resources and improving spectrum resource utilization at the overall system level. Specifically, the signal feature is embedded through cyclic delay diversity technology, so that the secondary user only needs very little prior information (cyclic delay amount) of the primary user to complete signal feature extraction and perception discrimination, and still has good detection performance under low signal-to-noise ratio.

[0011] In summary, feature embedding technology based on cyclic delay diversity has become the key to achieve dynamic spectrum hole perception and efficient use of spectrum resources. However, existing cyclic delay diversity technologies all consider the cyclic delay of signals transmitted by different antennas based on multi-antenna configuration, which cannot be applied to user feature embedding of single-antenna devices, especially difficult to apply to uplink transmission scenarios of IoT devices in cognitive radio networks. Summary of the invention

[0012] In view of the shortcomings of the prior art mentioned above, the purpose of the present invention is to provide a feature embedding method and system based on single-antenna cyclic delay diversity, expand the application of spectrum sensing based on feature detection to single-antenna devices, and provide a new solution for feature embedding of Internet of Things terminals.

[0013] In a first aspect, the present invention provides a feature embedding method based on single-antenna cyclic delay diversity, the method comprising the following steps: at a transmitting end, performing cyclic delays of different cyclic delay amounts on signals of different users to obtain corresponding cyclic delay signals, aliasing the signal of each user with the corresponding cyclic delay signal and transmitting the obtained aliased signal through a single antenna; at a receiving end, obtaining the cyclic delay amount of each user based on the aliased signal to identify the corresponding user based on the cyclic delay amount.

[0014] In an implementation manner of the first aspect, the transmitting end includes one or more antennas; when the transmitting end includes multiple antennas, the same aliasing signal is transmitted from each antenna.

[0015] In an implementation manner of the first aspect, the transmitting end is a base station, an access point or a user equipment; when the transmitting end is a base station or an access point, multi-user downlink transmission is performed; when the transmitting end is a user equipment, uplink transmission is performed.

[0016] In an implementation manner of the first aspect, the uplink transmission and the downlink transmission adopt an orthogonal multiple access mode or a non-orthogonal multiple access mode.

[0017] In an implementation manner of the first aspect, the receiving end performs autocorrelation processing on the aliasing signal to obtain a corresponding cyclic delay amount.

[0018] In a second aspect, the present invention provides a feature embedding system based on single-antenna cyclic delay diversity, the system comprising a transmitting end and a receiving end;

[0019] The transmitting end is used to perform cyclic delays of different cyclic delay amounts on signals of different users to obtain corresponding cyclic delay signals, alias the signal of each user and the corresponding cyclic delay signal, and transmit the obtained aliased signal through a single antenna;

[0020] The receiving end is used to obtain the cyclic delay of each user based on the aliasing signal, so as to identify the corresponding user based on the cyclic delay.

[0021] In an implementation manner of the second aspect, the transmitting end includes one or more antennas; when the transmitting end includes multiple antennas, the same aliasing signal is transmitted from each antenna.

[0022] In an implementation manner of the second aspect, the transmitting end is a base station, an access point or a user equipment; when the transmitting end is a base station or an access point, multi-user downlink transmission is performed; when the transmitting end is a user equipment, uplink transmission is performed.

[0023] In an implementation manner of the second aspect, the uplink transmission and the downlink transmission adopt an orthogonal multiple access mode or a non-orthogonal multiple access mode.

[0024] In an implementation manner of the second aspect, the receiving end performs autocorrelation processing on the aliasing signal to obtain a corresponding cyclic delay.

[0025] As described above, the feature embedding method and system based on single antenna cyclic delay diversity of the present invention have the following beneficial effects:

[0026] (1) Expand the application of spectrum sensing based on feature detection to single-antenna devices, providing a new solution for feature embedding in IoT terminals;

[0027] (2) It removes the hardware constraint that the transmitter must be equipped with dual or even multiple antennas, which is required by the traditional feature embedding method based on cyclic delay diversity. This provides a freer choice of the number of transmitter antennas for feature embedding of different users in the signal sensing system.

[0028] (3) It provides a new solution for signal perception and feature detection of miniaturized devices such as single-antenna IoT terminals, thereby further improving the spectrum perception capability of single-antenna terminal systems and thereby improving the spectrum utilization of the overall network. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Shown is a flow chart of a feature embedding method based on single-antenna cyclic delay diversity in one embodiment of the present invention;

[0030] Figure 2 Shown is a schematic structural diagram of a single-antenna cyclic delay diversity system in one embodiment;

[0031] Figure 3 Shown is a schematic structural diagram of a spectrum sensing system based on feature detection in one embodiment of the present invention;

[0032] Figure 4 It is a schematic diagram showing the structure of a feature embedding system based on single-antenna cyclic delay diversity in one embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0034] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0035] The feature embedding method and system based on single-antenna cyclic delay diversity of the present invention improves the spectrum sensing capability of the single-antenna terminal system by extending the application of spectrum sensing based on feature detection to single-antenna devices, thereby improving the spectrum utilization of the overall network.

[0036] like Figure 1 As shown, in one embodiment, the feature embedding method based on single antenna cyclic delay diversity of the present invention includes steps S1 and S2.

[0037] Step S1: At the transmitting end, cyclic delays of different cyclic delay amounts are performed on signals of different users to obtain corresponding cyclic delay signals, the signal of each user is aliased with the corresponding cyclic delay signal, and the obtained aliased signal is transmitted through a single antenna.

[0038] like Figure 2As shown in the figure, in a single-antenna cyclic delay diversity system, the original data U1 and U2 of different users are encoded and modulated to obtain signals x1 and x2 respectively. After the corresponding signals are cyclically shifted by different cyclic delay amounts Δ1 and Δ2, the signals of different users and the corresponding cyclic delay signals are aliased and transmitted through a single antenna. The different cyclic delay amounts corresponding to different user signals are the user cyclic stationary feature labels.

[0039] It should be noted that the transmitting end may be configured with multiple antennas or a single antenna, that is, it includes one or more antennas. When the transmitting end includes multiple antennas, each antenna transmits the same aliased signal, which is equivalent to transmitting the same single antenna signal through multiple antennas.

[0040] In one embodiment, the transmitting end is a base station, an access point or a user equipment. When the transmitting end is a base station or an access point, multi-user downlink transmission is performed; when the transmitting end is a user equipment, uplink transmission is performed. The uplink transmission and the downlink transmission adopt an orthogonal multiple access method or a non-orthogonal multiple access method.

[0041] Step S2: At the receiving end, the cyclic delay of each user is obtained based on the aliasing signal, so as to identify the corresponding user based on the cyclic delay.

[0042] Specifically, the receiving end performs autocorrelation processing on the aliasing signal to obtain a corresponding cyclic delay, thereby determining a user corresponding to the aliasing signal according to the cyclic delay, that is, performing user identification according to a user cyclic stationary feature label.

[0043] The feature embedding method based on single-antenna cyclic delay diversity of the present invention can expand the application scenarios of feature detection type spectrum sensing technology.

[0044] like Figure 3 The feature detection spectrum sensing system shown includes two single-antenna primary users (user-PU1, user-PU2) with high transmission priority, a single-antenna secondary user (user-SU) with secondary transmission priority, and an access point (access point-AP). User-PU1 and user-PU2 establish a connection with the access point-AP in an orthogonal or non-orthogonal multiple access manner and perform uplink transmission. User-SU simultaneously senses the transmission status of user-PU1 and user-PU2, that is, determines the idle state of the frequency band occupied by user-PU1 and user-PU2, and performs opportunistic access according to the results of spectrum sensing.

[0045] As the main users in the cognitive radio system, user-PU1 and user-PU2 need to embed user characteristics (i.e., cyclic delay) when transmitting signals so that user-SU can detect characteristics as the receiving end. Specifically, user-PU1 and user-PU2 perform differential cyclic delay processing on the signals based on the single antenna configuration and then transmit aliased signals. After receiving the aliased signals of user-PU1 and user-PU2, user-SU extracts user characteristics through signal autocorrelation processing to determine the transmission status of user-PU1 and user-PU2 respectively.

[0046] When the user-SU detects that the user-PU1 or the user-PU2 is in a non-transmitting state, the user-SU will dynamically occupy the spectrum resources of the user-PU1 or the user-PU2 and perform uplink transmission with the transmitting user in an orthogonal or non-orthogonal multiple access manner.

[0047] like Figure 4 As shown, in one embodiment, the feature embedding system based on single-antenna cyclic delay diversity of the present invention includes a transmitting end 41 and a receiving end 42.

[0048] The transmitting end 41 is used for performing cyclic delays of different cyclic delay amounts on signals of different users to obtain corresponding cyclic delay signals, aliasing the signal of each user with the corresponding cyclic delay signal and transmitting the obtained aliased signal through a single antenna.

[0049] like Figure 2 As shown in the figure, in a single-antenna cyclic delay diversity system, the original data U1 and U2 of different users are encoded and modulated to obtain signals x1 and x2 respectively. After the corresponding signals are cyclically shifted by different cyclic delay amounts Δ1 and Δ2, the signals of different users and the corresponding cyclic delay signals are aliased and transmitted through a single antenna. The different cyclic delay amounts corresponding to different user signals are the user cyclic stationary feature labels.

[0050] It should be noted that the transmitting end may be configured with multiple antennas or a single antenna, that is, it includes one or more antennas. When the transmitting end includes multiple antennas, each antenna transmits the same aliased signal, which is equivalent to transmitting the same single antenna signal through multiple antennas.

[0051] In one embodiment, the transmitting end is a base station, an access point or a user equipment. When the transmitting end is a base station or an access point, multi-user downlink transmission is performed; when the transmitting end is a user equipment, uplink transmission is performed. The uplink transmission and the downlink transmission adopt an orthogonal multiple access method or a non-orthogonal multiple access method.

[0052] The receiving end 42 is used to obtain the cyclic delay of each user based on the aliasing signal, so as to identify the corresponding user based on the cyclic delay.

[0053] Specifically, the receiving end performs autocorrelation processing on the aliasing signal to obtain a corresponding cyclic delay, thereby determining a user corresponding to the aliasing signal according to the cyclic delay, that is, performing user identification according to a user cyclic stationary feature label.

[0054] In summary, the feature embedding method and system based on single-antenna cyclic delay diversity of the present invention expands the application of spectrum sensing based on feature detection to single-antenna devices, providing a new solution for feature embedding of IoT terminals; removing the hardware constraint that the transmitter must be equipped with dual or even multiple antennas required by the traditional feature embedding method based on cyclic delay diversity, providing a freer choice of the number of transmitter antennas for feature embedding of different users in the signal sensing system; providing a new solution for signal sensing and feature detection of miniaturized devices such as single-antenna IoT terminals, thereby further improving the spectrum sensing capability of the single-antenna terminal system, and further improving the spectrum utilization of the overall network. Therefore, the present invention effectively overcomes the various shortcomings in the prior art and has a high industrial utilization value.

[0055] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A feature embedding method based on single-antenna cyclic delay diversity, characterized in that: The method comprises the following steps: At the transmitting end, cyclic delays of different cyclic delay amounts are performed on signals of different users to obtain corresponding cyclic delay signals, the signal of each user is aliased with the corresponding cyclic delay signal, and the obtained aliased signal is transmitted through a single antenna; At the receiving end, the cyclic delay of each user is obtained based on the aliasing signal, so as to identify the corresponding user based on the cyclic delay.

2. The feature embedding method based on single antenna cyclic delay diversity according to claim 1, characterized in that: The transmitting end includes one or more antennas; when the transmitting end includes multiple antennas, the same aliasing signal is transmitted from each antenna.

3. The feature embedding method based on single antenna cyclic delay diversity according to claim 1, characterized in that: The transmitting end is a base station, an access point or a user equipment; when the transmitting end is a base station or an access point, multi-user downlink transmission is performed; When the transmitting end is a user equipment, uplink transmission is performed.

4. The feature embedding method based on single antenna cyclic delay diversity according to claim 3, characterized in that: The uplink transmission and the downlink transmission adopt an orthogonal multiple access mode or a non-orthogonal multiple access mode.

5. The feature embedding method based on single antenna cyclic delay diversity according to claim 1, characterized in that: The receiving end performs autocorrelation processing on the aliased signal to obtain a corresponding cyclic delay.

6. A feature embedding system based on single-antenna cyclic delay diversity, characterized in that: The system includes a transmitting end and a receiving end; The transmitting end is used to perform cyclic delays of different cyclic delay amounts on signals of different users to obtain corresponding cyclic delay signals, alias the signal of each user and the corresponding cyclic delay signal, and transmit the obtained aliased signal through a single antenna; The receiving end is used to obtain the cyclic delay of each user based on the aliasing signal, so as to identify the corresponding user based on the cyclic delay.

7. The feature embedding system based on single antenna cyclic delay diversity according to claim 6, characterized in that: The transmitting end includes one or more antennas; when the transmitting end includes multiple antennas, the same aliasing signal is transmitted from each antenna.

8. The feature embedding system based on single antenna cyclic delay diversity according to claim 6, characterized in that: The transmitting end is a base station, an access point or a user equipment; when the transmitting end is a base station or an access point, multi-user downlink transmission is performed; When the transmitting end is a user equipment, uplink transmission is performed.

9. The feature embedding system based on single antenna cyclic delay diversity according to claim 8, characterized in that: The uplink transmission and the downlink transmission adopt an orthogonal multiple access mode or a non-orthogonal multiple access mode.

10. The feature embedding system based on single antenna cyclic delay diversity according to claim 6, characterized in that: The receiving end performs autocorrelation processing on the aliased signal to obtain a corresponding cyclic delay.

Images