Method for coordination of wireless transceivers of a network node and network node

• US 8,902,917 B2
• Filed: 05/29/2009
• Issued: 12/02/2014
• Est. Priority Date: 05/29/2009
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Europe Ltd (NEC Corporation)
• Inventors: Le, Long, Baldessari, Roberto, Festag, Andreas, Zhang, Wenhui
• Primary Examiner(s): Masur, Paul H
• Application Number:
  US13/322,999
• Publication Number:
  US 20120134342A1
• Time in Patent Office: 2,013 Days
• Field of Search: 370/338, 370/431, 370/445
• US Class Current: 370/435
• CPC Class Codes: H04W 72/52 based on load
• CPC Class Codes: H04W 72/566 of the information or information source or recipient

Abstract

A method for coordination of wireless transceivers of a network node, in particular for application in communication nodes of a vehicular network, wherein the network node is equipped with one or more wireless transceivers that are capable of simultaneously generating and/or receiving electromagnetic signals on different electromagnetic channels, the electromagnetic signals being potentially able to interfere with each other, is characterized in the steps of, for each pending packet transmission on a particular of the electromagnetic channels, checking the presence of ongoing and/or scheduled activity on one or more of the other of the electromagnetic channels, and deferring the pending packet transmission in case ongoing and/or scheduled activity is detected on one or more of the other of the electromagnetic channels, at least until the detected ongoing and/or scheduled activity on one or more of the other of the electromagnetic channels is completed. Furthermore, a corresponding network node is disclosed.

Claims

1. A method for coordination of wireless transceivers of a network node, wherein said network node is equipped with one or more wireless transceivers that are capable of simultaneously generating and/or receiving electromagnetic signals on different electromagnetic channels, comprising the steps of:

for each pending packet transmission on a particular of said electromagnetic channels, checking the presence of ongoing and/or scheduled activity on one or more of the other of said electromagnetic channels; and

deferring said pending packet transmission in case ongoing and/or scheduled activity is detected on one or more of the other of said electromagnetic channels, at least until said detected ongoing and/or scheduled activity on one or more of the other of said electromagnetic channels is completed,

wherein a scheduling of packet transmissions on said electromagnetic channels is realized with packet-level granularity by applying the deferring step before the packet has reached the physical layer, either at the Medium Access Control (MAC) layer or at a layer above the MAC layer, and

wherein said deferring of a pending packet transmission is applied after the MAC layer access contention is completed and said network node has acquired the right to transmit.

2. The method according to claim 1, wherein said pending packet transmission on a particular of said electromagnetic channels is carried out as soon as said detected ongoing and/or scheduled activity on one or more of the other of said electromagnetic channels is completed.

3. The method according to claim 2,

wherein said deferring of a pending packet transmission is realized by deferring the passing down of said packet from the network layer or a generic upper layer to the MAC layer, and/or

wherein said deferring of a pending packet transmission and said packet transmission are both carried out in the same transmission opportunity obtained by said network node.

4. The method according to claim 2,

wherein said checking of ongoing and/or scheduled activity is restricted to checking the presence of any transmissions on one or more of the other of said electromagnetic channels, or

wherein said ongoing and/or scheduled activity that is checked includes the presence of transmissions and receptions on one or more of the other of said electromagnetic channels.

5. The method according to claim 1,

wherein said deferring of a pending packet transmission is realized by deferring the passing down of said packet from the network layer or a generic upper layer to the MAC layer, and/or

wherein said deferring of a pending packet transmission and said packet transmission are both carried out in the same transmission opportunity obtained by said network node.

6. The method according to claim 1,

wherein said checking of ongoing and/or scheduled activity is restricted to checking the presence of any transmissions on one or more of the other of said electromagnetic channels, or

wherein said ongoing and/or scheduled activity that is checked includes the presence of transmissions and receptions on one or more of the other of said electromagnetic channels.

7. The method according to claim 1,

wherein said electromagnetic channels include at least one channel with high priority and at least one channel with low priority, and wherein pending packet transmissions via said at least one low-priority channel are deferred until transmission of all packets waiting to be sent via said at least one high-priority channel is completed,

wherein pending packet transmissions via said at least one low-priority channel may be deferred until transmission of all packets newly arriving for said at least one high-priority channel during active transmission via that channel is completed, and/or

wherein transmissions via said at least one low-priority channel may be restricted in that after each single packet transmission completion, the packet transmissions pending for the low-priority channels yield those pending for the high-priority channels.

8. The method according to claim 1, wherein said electromagnetic channels contain at least one control channel and one service channel, and the transmission and/or reception of said control channel is prioritized to the transmission and/or reception of said service channel.

9. The method according to claim 1, wherein said electromagnetic channels contain at least one channel allocated for safety-related communication and another channel allocated for non-safety-related communication, and the transmission and/or reception of said channel allocated for safety-related communication is prioritized to the transmission and/or reception of said channel allocated for non-safety-related communication.

10. The method according to claim 1, wherein the completion of said detected ongoing and/or scheduled activity triggers the provision of a respective inter-channel notification by the physical layer.

11. The method according to claim 1,

wherein said network node is configured to maintain counters to keep track of ongoing and pending transmissions at the physical layer on each of said different electromagnetic channels, and

wherein said counter for an electromagnetic channel may be incremented when a packet is passed down to the physical layer for transmission on that electromagnetic channel, and wherein said counter may be decremented when the transmission of a packet on that electromagnetic channel is completed.

12. The method according to claim 1, wherein a shared data structure is provided in which each of said different electromagnetic channels has a status entry.

13. A network node, comprising:

one or more wireless transceivers that are capable of simultaneously generating and/or receiving electromagnetic signals on different electromagnetic channels,

wherein said wireless transceivers include detection means that check for each pending packet transmission on a particular one of said electromagnetic channels, the presence of ongoing and/or scheduled activity on one or more other of said electromagnetic channels,

wherein said wireless transceivers are configured to defer said pending packet transmission in case ongoing and/or scheduled activity is detected on the one or more of the other of said electromagnetic channels, at least until the completion of said detected ongoing and/or scheduled activity on the one or more of the other of said electromagnetic channels is completed,

wherein a scheduling of packet transmissions on said electromagnetic channels is realized with packet-level granularity by deferring packet transmission before the packet has reached the physical layer, either at the Medium Access Control (MAC) layer or at a layer above the MAC layer, and

wherein said pending packet transmission is deferred by deferring said pending packet transmission after the MAC layer access contention is completed and said network node has acquired the right to transmit.

14. The network node according to claim 13, wherein said transceivers include multiple wireless LAN (local area network) transmitters, in particular based on the IEEE 802.11 standard family.

15. The network node according to claim 14, further comprising:

a single wide-band transmitter that is capable of simultaneously transmitting two or more signals on two or more different electromagnetic channels.

16. The network node according to claim 14, further comprising:

an on-board unit for vehicular communication that is equipped with two or more transceivers,

wherein said two or more transceivers may be temporarily or permanently tuned to adjacent or near electromagnetic channels, and/or

wherein at least two of said transceivers may be tuned to different electromagnetic channels in the same frequency band, and/or

wherein at least two of said transceivers may share a single antenna.

17. The network node according to claim 13, further comprising:

a single wide-band transmitter that is capable of simultaneously transmitting two or more signals on two or more different electromagnetic channels.

18. The network node according to claim 13, further comprising:

an on-board unit for vehicular communication that is equipped with two or more transceivers,

wherein said two or more transceivers may be temporarily or permanently tuned to adjacent or near electromagnetic channels, and/or

wherein at least two of said transceivers may be tuned to different electromagnetic channels in the same frequency band, and/or

wherein at least two of said transceivers may share a single antenna.

19. The network node according to claim 17,

wherein one or more of said transceivers are tuned to two different electromagnetic channels in the frequency band allocated by the European Commission for Intelligent Transport System (ITS) applications or allocated by the Federal Communications Commission (FCC) of the United States of America, belonging to the frequency range 5.855-5.925 GHz,

wherein at least one of said transceivers may be tuned to the Control Channel as defined by the ETSI TC ITS specifications, and wherein at least one of said transceivers may be tuned to one of the Service Channels as defined by the ETSI TC ITS specifications.