Receiver and transmitter for a network having a non-centralized medium access control

• US 7,848,706 B2
• Filed: 08/27/2007
• Issued: 12/07/2010
• Est. Priority Date: 02/25/2005
• Status: Expired due to Fees

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Kusume, Katsutoshi, Vilzmann, Robert, Hartmann, Christian, Bettstetter, Christian, Bauch, Gerhard
• Primary Examiner(s): Milord; Marceau
• Application Number:
  US11/895,988
• Publication Number:
  US 20080039046A1
• Time in Patent Office: 1,198 Days
• Field of Search: 455/63.1, 455/67.11, 455/67.13, 455/69, 455/562.1, 455/412.1, 455/456.2, 455/277.1, 375/267, 375/325, 375/346, 375/348, 370/335, 370/445
• US Class Current: 455/63.1
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 74/0825 with collision detection

Abstract

A receiver includes a receiving unit for scanning a dedicated signaling channel for the presence of an announcement signal. The announcement signal indicates a transmitter willing to access a transmission medium. The receiving unit is further operative to receive a data signal from a further transmitter on a dedicated traffic channel. Furthermore, the receiver includes an interference estimator for estimating, whether an interference caused by a new transmitter is allowable or not. A processor is provided for applying an interference counter-measure, when the interference is not allowable. A transmitter can, without any limitation, transmit the announcement signal. The transmitter will start transmitting, when it receives a ready-to-receive signal from the addressed receiver and when it does not receive an objection tone from another receiver in the network.

Claims

1. A receiver for a network comprising a non-centralized medium access control, comprising:

a receiving unit for scanning a dedicated signaling channel for the presence of an announcement signal, the announcement signal indicating a transmitter willing to access the transmission medium, and for receiving a data signal from a further transmitter on a dedicated traffic channel;

an interference estimator for estimating, whether an interference on the traffic channel caused by a potential medium access of the transmitter transmitting the announcement signal is allowable or not; and

a processor for applying an interference counter-measure, when the interference is not allowable.

2. The receiver in accordance with claim 1, in which the dedicated signaling channel and the traffic channel are selected such that a channel characteristic of the traffic channel depends on a channel characteristic of the signaling channel, and

wherein the interference estimator is operative to estimate the interference based on the announcement signal scanned by the receiving unit.

3. The receiver in accordance with claim 1, in which the traffic channel occupies a frequency band of the transmission medium and the signaling channel occupies at least a part of the same frequency band of the transmission medium, the announcement signal being encoded using an encoding scheme to enable extracting the announcement signal from a superposition of the data signal and the announcement signal,

wherein the receiving unit is operative to receive a channel signal in the frequency band, to extract a signal portion from the channel signal using information on the encoding scheme, and to detect the announcement signal in the signal portion.

4. The receiver in accordance with claim 3, in which the encoding scheme is a multiple access encoding scheme reserved for encoding announcement signals, and wherein the receiving unit is adapted for extracting the signal portion by applying an inverse multiple access scheme to the channel signal.

5. The receiver in accordance with claim 4, in which the multiple access scheme is a CDMA scheme or an IDMA scheme.

6. The receiver in accordance with claim 1, wherein the receiving unit is adapted for performing a reception beam pattern comprising a main reception lobe directed to the further transmitter.

7. The receiver in accordance with claim 1, in which the interference estimator is operative to only be active, when an identifier included in the announcement signal does not identify the receiver.

8. The receiver in accordance with claim 1, in which the processor is operative to cause, as a counter-measure, a transmission of an objection tone by the receiver for informing the transmitter that the transmission is not allowed.

9. The receiver in accordance with claim 1, in which the processor is operative, as a counter-measure, to detect a direction of incidence of the announcement signal and to control the receiving unit for reducing a receiving antenna gain in the direction of incidence.

10. The receiver in accordance with claim 1, in which the processor is operative to apply, as a counter-measure, a multi-user detection scheme or an interference cancellation scheme based on a known characteristic of the transmitter, the further transmitter or the receiver.

11. The receiver in accordance with claim 1, in which the processor is operative to apply, as a counter-measure, a negotiation with the further transmitter for improved transmission robustness including a higher transmission power or a higher data redundancy.

12. The receiver in accordance with claim 1, in which the processor is operative to apply, as a counter-measure, a negotiation with the transmitter sending the announcement signal for less transmission power.

13. The receiver in accordance with claim 1, in which the interference estimator is operative to determine a power or an energy of the announcement signal and a power or an energy of the data signal and to estimate, whether the interference is allowable or not based on a relation between the determined values.

14. The receiver in accordance with claim 1, in which the interference estimator is operative to evaluate the following equation:

15. The receiver in accordance with claim 1, in which the processor is operative to transmit, as a counter-measure, an objection signal, the objection signal being transmitted within a further signaling channel, which is different from the traffic channel.

16. The receiver in accordance with claim 15, in which the further signaling channel is an out-of-band channel.

17. The receiver in accordance with claim 1, further comprising:

an identification detector for indicating that the receiver is identified by the transmitter, and

wherein the processor is further operative to cause a transmission of a ready-to-receive signal, when the receiver is not receiving data from the further transmitter via the traffic channel.

18. The receiver in accordance with claim 17, in which the receiver is operative to detect a direction of incidence of a signal from the transmitter and to control the receiving unit to increase a receiving antenna gain in the detected direction of incidence.

19. The receiver in accordance with claim 1, wherein the receiving unit is adapted for applying a direction-dependent reception characteristic for receiving the channel signal and for applying a further reception characteristic for receiving a further channel signal for deafness detection.

20. The receiver in accordance with claim 19, wherein the receiving unit is adapted for applying the direction-dependent reception characteristic during a time interval, and for applying the further reception characteristic during another time interval.

21. The receiver in accordance with claim 19, further comprising a transmission unit adapted for transmitting the deafness signal for the communication network within a further dedicated signaling channel, in order to indicate that the receiver is not capable of capturing a signal from a direction of arrival associated with the transmitter when applying the direction-dependent reception characteristic directed to the further transmitter.

22. The receiver in accordance with claim 19, in which the receiver is operative to detect a deafness situation only when the receiver is identified as a receiver addressed by the transmitter.

23. A transmitter for a network comprising a non-centralized medium access control, comprising:

a transmitting unit for transmitting an announcement signal on a dedicated signaling channel, the announcement signal indicating that the transmitter is willing to access the transmission medium and to communicate with an addressed receiver;

a receiving unit for listening for an objection signal from a non-addressed receiver; and

a processor for controlling the transmission unit to start transmitting a data signal on a dedicated data channel only when no objection signal has been received.

24. The transmitter in accordance with claim 23,

in which the receiving unit is operative to listen to a ready-to-receive signal from the addressed receiver, and

in which the processor is further operative to control the transmission unit to start transmitting a data signal on a dedicated data channel only when a ready-to receive signal from the addressed receiver has been received and no objection signal has been received.

25. The transmitter in accordance with claim 24, in which the transmitting unit is adapted for transmitting the announcement signal using the same beamforming pattern, which is to be used when transmitting the data signal.

26. The transmitter in accordance with claim 23, in which the receiving unit is adapted to receive the ready-to-receive signal in the same signaling channel as the announcement signal has been transmitted and to receive an objection signal in a different signaling channel.

27. The transmitter in accordance with claim 23, in which the receiving unit is operative to receive the objection signal in a frequency band, which is not covered by the traffic channel.

28. The transmitter in accordance with claim 23, in which the processor is operative to control the transmission unit to start transmission, when no objection signal within a predetermined time period has been received.

29. A method of receiving in a network comprising a non-centralized medium access control, comprising:

scanning a dedicated signaling channel for the presence of an announcement signal, the announcement signal indicating a transmitter willing to access the transmission medium,

receiving a data signal from a further transmitter on a dedicated traffic channel;

estimating, whether an interference on the traffic channel caused by a potential medium access of the transmitter transmitting the announcement signal is allowable or not; and

applying an interference counter-measure, when the interference is not allowable.

30. A method of transmitting in a network comprising a non-centralized medium access control, comprising:

transmitting an announcement signal on a dedicated signaling channel, the announcement signal indicating that the transmitter is willing to access the transmission medium and to communicate with an addressed receiver;

listening for an objection signal from a non-addressed receiver; and

starting a transmission of a data signal on a dedicated data channel only when no objection signal has been received.

31. A computer program for performing, when the program runs on a computer, a method of receiving in a network comprising a non-centralized medium access control, comprising:

scanning a dedicated signaling channel for the presence of an announcement signal, the announcement signal indicating a transmitter willing to access the transmission medium,

receiving a data signal from a further transmitter on a dedicated traffic channel;

estimating, whether an interference on the traffic channel caused by a potential medium access of the transmitter transmitting the announcement signal is allowable or not; and

applying an interference counter-measure, when the interference is not allowable.

32. A computer program for performing, when the program runs on a computer, a method of transmitting in a network comprising a non-centralized medium access control, comprising:

transmitting an announcement signal on a dedicated signaling channel, the announcement signal indicating that the transmitter is willing to access the transmission medium and to communicate with an addressed receiver;

listening for an objection signal from a non-addressed receiver; and

starting a transmission of a data signal on a dedicated data channel only when no objection signal has been received.