阅读说明：本技术 时分双工通信中的干扰 (Interference in time division duplex communication ) 是由 哈南·莱泽罗维奇 阿萨夫·蒙萨彻蒙 于 2019-07-17 设计创作，主要内容包括：提出了一种用于断开两个节点之间的无线时分双工通信链路的方法。第一节点在分配给第一节点的时隙期间传输,并且第二节点在分配给第二节点的单独的时隙期间传输。该第一节点在其时隙期间在不同的相应频带处传输。该方法包括：将分配给第一节点的时隙细分成连续时间间隔；以及在该时间间隔期间传输相应的断开信号。每个断开信号在由第一节点使用的频带上传输。在该时间间隔中的至少两个时间间隔期间,该断开信号在不同的频带上传输。(A method for disconnecting a wireless time division duplex communication link between two nodes is presented. The first node transmits during the time slot assigned to the first node and the second node transmits during a separate time slot assigned to the second node. The first node transmits at different respective frequency bands during its time slot. The method comprises the following steps: subdividing the time slot allocated to the first node into successive time intervals; and transmitting a corresponding disconnect signal during the time interval. Each disconnect signal is transmitted on a frequency band used by the first node. The disconnect signal is transmitted on different frequency bands during at least two of the time intervals.)

1. A method for breaking a wireless time division duplex communication link between a first node and a second node, the first node transmitting during a time slot assigned to the first node, the second node transmitting during a separate time slot assigned to the second node, the first node transmitting at a respective one of a plurality of frequency bands during each of the time slots assigned to the first node, the method comprising:

subdividing a time slot allocated to the first node into successive time intervals;

transmitting, using a transmitter, respective turn-off signals during a plurality of said time intervals, each said turn-off signal being transmitted on a respective one of said plurality of frequency bands, wherein for at least two of said time intervals, said turn-off signals are transmitted on different frequency bands.

2. The method of claim 1, wherein the turn-off signal is data modulated for at least one of the time intervals.

3. The method of claim 1, wherein the turn-off signal is modulated by a turn-off command for the second node for at least one of the time intervals.

4. The method of claim 1, wherein the turn-off signal is modulated by a pseudo-random data sequence for at least one of the time intervals.

5. The method of claim 1, wherein for at least one of the time intervals, the turn-off signal comprises one of:

predefining an interference signal; and

a random noise signal.

6. The method of claim 1, further comprising:

monitoring transmissions by the second node; and

predicting an upcoming time slot of the first node based on the monitored transmissions.

7. The method of claim 1, further comprising initiating the transmission of the disconnect signal upon detecting that transmission by the second node ceased.

8. The method of claim 1, further comprising:

analyzing transmissions by the second node to identify a disconnection of communications between the first node and the second node; and

establishing direct communication with the second node when the disconnection is identified.

9. The method of claim 1, further comprising selecting the respective frequency band from a specified list of frequency bands.

10. The method of claim 1, wherein a disconnect signal is transmitted during a single time slot over an entire frequency range used by the first node.

11. The method of claim 1, wherein the first node transmits in a known order of the frequency bands, further comprising:

transmitting the disconnect signals in the known sequence; and

changing the phase of the sequence of transmitted disconnect signals by transmitting one of the disconnect signals at a frequency band outside of the known sequence and continuing subsequent disconnect signal transmissions in the known sequence.

12. The method of claim 1, wherein the entire frequency range used by the first node is interfered by the disconnect signal during a single time slot of the first node.

13. The method of claim 1, further comprising transmitting at least two disconnect signals in parallel on a respective one of the frequency bands for at least one of the time intervals, wherein the number of disconnect signals transmitted in parallel is less than the total number of frequency bands.

14. The method of claim 1, further comprising transmitting a first subset of the frequency bands during the time slot of the first node and transmitting a second subset of the frequency bands during a subsequent time slot of the first node.

15. A method for controlling an apparatus of interfering wireless time division duplex communication between a first node and a second node, the first node transmitting during a time slot allocated to the first node, the second node transmitting during a separate time slot allocated to the second node, the first node transmitting at a respective one of a plurality of frequency bands during each of the time slots allocated to the first node, the method comprising:

receiving a wireless transmission from the second node using a receiver;

determining a time slot allocated to the first node based on the received transmission and subdividing the determined time slot into successive time intervals; and

instructing the apparatus to transmit respective turn-off signals during a plurality of the time intervals, each of the turn-off signals for transmission on a respective one of the plurality of frequency bands, wherein the turn-off signals are transmitted on different frequency bands for at least two of the time intervals.

16. The method of claim 15, further comprising providing at least one signal parameter to the apparatus for generating the disconnect signal.

17. The method of claim 16, wherein the at least one signal parameter comprises:

the type of disconnect signal to be transmitted;

data for modulating onto the disconnect signal;

a duration of the time slot;

a respective duration of the time interval;

the respective frequency band of the disconnect signal;

a respective transmission power of the turn-off signal; and

the number of disconnect signals to be transmitted in parallel.

18. The method of claim 15, wherein the indicating comprises instructing the apparatus to transmit a disconnect command on at least one of the disconnect signals to disconnect the second node from the first node.

19. The method of claim 15, further comprising:

detecting a disconnection of communication between the first node and the second node from the received transmission; and

instructing the apparatus to establish direct communication with the second node.

20. An apparatus for breaking a wireless time division duplex communication link between a first node and a second node, the first node transmitting during a time slot assigned to the first node, the second node transmitting during a separate time slot assigned to the second node, the first node transmitting at a respective one of a plurality of frequency bands during each of the time slots assigned to the first node, the apparatus comprising:

a signal generator adapted to:

subdividing a time slot allocated to the first node into successive time intervals; and

generating respective turn-off signals for a plurality of said time intervals, each of said turn-off signals occupying a respective one of said plurality of frequency bands, wherein for at least two of said time intervals, said turn-off signals occupy different frequency bands; and

a wireless transmitter associated with the signal generator adapted to transmit the disconnect signal at the respective time interval.

21. The apparatus of claim 20, wherein for at least one of the time intervals, the turn-off signal is modulated by one of:

a disconnect command for the second node;

a pseudo-random data sequence;

predefining an interference sequence; and

a noise signal.

22. The apparatus of claim 20, wherein the signal generator is further adapted to select the respective frequency band of the disconnect signal from a specified list of frequency bands.

23. The apparatus according to claim 20, wherein the signal generator is further adapted to select the respective frequency band of the disconnect signal as a succeeding frequency band within a frequency range used by the first node.

24. The apparatus of claim 20, wherein an entire frequency range used by the first node is interfered with by the disconnect signal during a single time slot of the first node.

25. A controller for a wireless disconnect device for interfering with a wireless time division duplex communication link between a first node and a second node, the first node transmitting during a time slot assigned to the first node, the second node transmitting during a separate time slot assigned to the second node, the first node transmitting at a respective one of a plurality of frequency bands during each of the time slots assigned to the first node, the controller comprising:

a receiver adapted to receive a wireless transmission from the second node;

a signal analyzer associated with the receiver adapted to:

determining a time slot allocated to the first node based on the received transmission;

subdividing the time slot into successive time intervals; and

instructing the disconnect device to transmit respective disconnect signals during a plurality of the time intervals, each of the disconnect signals for transmission on a respective one of the plurality of frequency bands, wherein the disconnect signals are transmitted on different frequency bands for at least two of the time intervals.

26. The controller of claim 25, further adapted to instruct the disconnect device to transmit a disconnect signal for disconnecting the second node from the first node on at least one of the disconnect signals.

27. The controller of claim 25, further adapted to provide at least one signal parameter to the disconnect device for generating the disconnect signal, the at least one signal parameter comprising:

the type of disconnect signal to be transmitted;

data for modulating onto the disconnect signal;

a duration of the time slot;

a respective duration of the time interval;

the respective frequency band of the disconnect signal; and

the respective transmission power of the turn-off signal.

28. The controller of claim 25, wherein the signal analyzer is further adapted to:

detecting a disconnection of communication between the first node and the second node from the received transmission; and

instructing the disconnecting means to establish direct communication with the second node.

Field and background of the invention

In some embodiments thereof, the present invention relates to time division duplex communication (time division duplex communication), and more particularly, but not exclusively, to interfering with time division duplex communication.

In Time Division Duplex (TDD) communications, transmissions by a network node are divided into different time slots. In some cases, the nodes use different transmission schemes. For example, during their respective time slots allocated to one node transmits a frequency-hopping packet, while a second node transmits a fixed-frequency packet.

Time division duplexing has a strong advantage in case the uplink and downlink data rates are not symmetric. More communication capacity may be dynamically allocated as the amount of uplink data increases, and capacity may be taken away as traffic load changes are light.

In some cases, a wideband jamming signal is used to interrupt communication uplink and/or downlink communications. To interfere with the node B's reception of the transmission from node a, a broadband interference signal is transmitted towards the node B. The interference signal may be a high Bandwidth (BW) noise signal, such as white gaussian noise, or any other wideband signal, such as actual data or chirp signal.

One drawback of broadband interference solutions is the possible interference to other communication links in the area. Another disadvantage is power loss, since power is distributed over the entire bandwidth. Furthermore, interference solutions do not use a disconnect command and therefore can only cause two nodes to disconnect by increasing the Bit Error Rate (BER) in the reception of node a by node B.

Another approach to this problem is to transmit pulsed interfering signals in parallel at all known frequencies used by node a during the node a time slot. The drawback of the above solution is still power loss, since the power is distributed over the entire frequency range of node a. Also, as with the previous solution, this jamming technique does not include a disconnect command.

Additional background art includes:

[1] "Jamming a TDD Point-to-Point Link Using sensitivity-Based MIMO" by Karlsson et al, IEEE Transactions on Information strategies and Security,12(12), pp.2957-2970,2017, 11/7.

[2] International patent application publication No. WO 93/26124.

[3] Grover et al, "Jamming and Anti-Jamming Techniques in Wireless Networks A Survey", International Journal of Ad Hoc and Ubiquitous Computing, Vol.17, No. 4, p.197 and 215, 2014 12.

[4] International patent application publication No. WO 93/22850.

[5] Parlin, "Jamming OF Spread Spectrum Communications Used in UAV Remote Control Systems," TALLINN UNIVERSITY OF TECHNOLOGY School OF Information Technologies, 2017.

Disclosure of Invention

Embodiments of the present invention are directed to disconnecting and/or interfering with communications between nodes in a TDD communication link in which at least one node (denoted herein as node a) transmits at different respective frequency bands during different time slots (i.e., frequency hopping) allocated thereto. Transmissions by node a are interfered with by transmitting a series of high power short turn-off signals during each time slot assigned to node a. Each disconnect signal is transmitted during a respective time interval within a node a time slot. Because the disconnect device transmits only within a single node a frequency band at any given time interval, the transmit power of the disconnect signal may be maximized at each frequency band during a portion of the node a time slot. Optionally, the disconnect signal is modulated with a disconnect command that, when received by node B, causes node B to disconnect from node a. Optionally, the disconnect signal may be a predefined pattern and/or noise signal intended to interfere with communication between node a and node B.

In some embodiments, the disconnect signal is transmitted in more than one frequency band during a given time interval. Although in this embodiment the transmission power is allocated among a plurality of frequency bands, the transmission power is still higher than in the case where the turn-off signal covers the entire node a frequency range.

According to a first aspect of some embodiments of the present invention there is provided a method for breaking a wireless time division duplex communication link between a first node and a second node, the first node transmitting during a time slot allocated to the first node and the second node transmitting during a separate time slot allocated to the second node. The first node transmits at different respective frequency bands during its time slot. The method comprises the following steps:

subdividing the time slot allocated to the first node into successive time intervals; and transmitting a respective disconnect signal during the time interval.

Each disconnect signal is transmitted on a frequency band used by the first node. The disconnect signal is transmitted on different frequency bands during at least two of the time intervals.

According to a second aspect of some embodiments of the present invention there is provided an apparatus for disconnecting a wireless time division duplex communication link between a first node transmitting during a time slot allocated to the first node and a second node transmitting during a separate time slot allocated to the second node. The first node transmits at different respective frequency bands during its time slot. The apparatus includes a signal generator and a wireless transmitter. The signal generator subdivides the time slot allocated to the first node into successive time intervals and generates respective turn-off signals for a plurality of time intervals. Each of the disconnect signals occupies a respective one of the frequency bands. The disconnect signal is on different frequency bands for at least two of the time intervals. The wireless transmitter transmits a disconnect signal at corresponding time intervals.

According to some embodiments of the first or second aspect of the present invention, the turn-off signal is data modulated for at least one of the time intervals.

According to some embodiments of the first or second aspect of the present invention, the switch-off signal is modulated by a switch-off command for the second node for at least one of the time intervals.

According to some embodiments of the first or second aspect of the present invention, the turn-off signal is modulated by a pseudo-random data sequence for at least one of the time intervals.

According to some embodiments of the first or second aspect of the present invention, for at least one of the time intervals, the turn-off signal is one of: a predefined disturbing signal (predefined jamming signal) and a random noise signal.

According to some embodiments of the first or second aspect of the present invention, transmissions by the second node are monitored and an upcoming time slot of the first node is predicted based on the monitored transmissions.

According to some embodiments of the first or second aspect of the present invention, the transmission of the disconnect signal is initiated when a cessation of transmission by the second node is detected.

According to some embodiments of the first or second aspect of the present invention, the transmission by the second node is analysed to identify a disconnection of communication between the first and second nodes, and when such a disconnection is identified, direct communication is established with the second node.

According to some embodiments of the first or second aspect of the present invention, the respective frequency band is selected from a specified list of frequency bands.

According to some embodiments of the first or second aspect of the present invention, the disconnect signal is transmitted during a single time slot over the entire frequency range used by the first node.

According to some embodiments of the first or second aspect of the present invention, the first node transmits in a known order of frequency bands and transmits the disconnect signal in the known order. The phase of the sequence of transmitted disconnect signals is changed by transmitting one of the disconnect signals at a frequency band outside the known sequence and continuing subsequent disconnect signal transmissions in the known sequence. This phase change may be performed multiple times while interfering with the transmission.

According to some embodiments of the first or second aspect of the present invention, the entire frequency range used by the first node is interfered by the disconnect signal during a single time slot of the first node.

According to some embodiments of the first or second aspect of the present invention, the respective frequency band of the turn-off signal is selected as a contiguous frequency band (contiguous frequency bands) within a frequency range used by the first node.

According to some embodiments of the first or second aspect of the present invention, for at least one of the time intervals, at least two disconnect signals are transmitted in parallel on respective ones of the frequency bands. The number of parallel transmitted disconnect signals is less than the total number of frequency bands.

According to some embodiments of the first or second aspect of the present invention, the first subset of the frequency band is transmitted during a time slot of the first node and the second subset of the frequency band is transmitted during a subsequent time slot of the first node.

According to a third aspect of some embodiments of the present invention, there is provided a method for controlling an apparatus of interfering wireless time division duplex communication. The time division duplex communication is between a first node transmitting during a time slot assigned to the first node and a second node transmitting during a separate time slot assigned to the second node. The first node transmits at different respective frequency bands during its time slot. The method comprises the following steps:

receiving a wireless transmission from the second node using a receiver;

determining a time slot allocated to the first node based on the received transmission and subdividing the determined time slot into successive time intervals; and

instructing the apparatus to transmit a respective turn-off signal during a plurality of the time intervals, each of the turn-off signals for transmission on a respective one of the plurality of frequency bands, wherein the turn-off signal is transmitted on a different frequency band for at least two of the time intervals.

According to a fourth aspect of some embodiments of the present invention there is provided a controller for a wireless disconnect device for interfering with a wireless time division duplex communication link. The time division duplex communication is between a first node transmitting during a time slot assigned to the first node and a second node transmitting during a separate time slot assigned to the second node. The first node transmits at different respective frequency bands during its time slot. The device includes:

a receiver that receives a wireless transmission from the second node;

a signal analyzer, the signal analyzer:

determining a time slot allocated to the first node based on the received transmission;

subdividing the time slot into successive time intervals; and

instructing the disconnect device to transmit a respective disconnect signal during a plurality of the time intervals, each disconnect signal for transmission on a respective one of the plurality of frequency bands, wherein the disconnect signal is transmitted on a different frequency band for at least two of the time intervals.

According to some embodiments of the third or fourth aspect of the present invention, at least one signal parameter for generating the disconnect signal is provided to the apparatus. According to some further embodiments of the third or fourth aspect of the present invention, the signal parameter comprises:

the type of disconnect signal to be transmitted;

data for modulating onto the disconnect signal;

the duration of the time slot;

the respective duration of the time interval;

the respective frequency band of the turn-off signal;

the respective transmission power of the turn-off signal; and

the number of disconnect signals to be transmitted in parallel.

According to some embodiments of the third or fourth aspect of the present invention, the apparatus is instructed to transmit a disconnect command for disconnecting the second node from the first node on at least one of the disconnect signals.

According to some embodiments of the third or fourth aspect of the present invention, a disconnection of communication between the first node and the second node is detected from the received transmission, and the apparatus is instructed to establish direct communication with the second node.

Unless defined otherwise, all technical and/or scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, exemplary methods and/or materials are described below. In case of conflict, the patent specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.