Method for channel state measurement in multi-mode multi-hop wireless networks

• US 9,125,097 B2
• Filed: 10/08/2010
• Issued: 09/01/2015
• Est. Priority Date: 10/08/2009
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Salonidis, Theodoros, Subramanian, Anand Prabhu, Lundgren, Henrik, Towsley, Don
• Primary Examiner(s): Javaid, Jamal
• Assistant Examiner(s): BUTT, WALLI Z
• Application Number:
  US13/500,507
• Publication Number:
  US 20120195225A1
• Time in Patent Office: 1,789 Days
• Field of Search: 370/230, 370/241, 370/242, 370252-258, 370/312, 370321-337, 370/345, 370/350, 370/356, 370/445, 370/503, 455/423, 455/500, 455/561, 709/242, 709/209, 709/248
• US Class Current: 1/1
• CPC Class Codes: H04W 24/10 Scheduling measurement reports ; Arrangements for measurement reports
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

The invention concerns a method for measuring channel state information of multiple transmission/reception modes in a wireless network comprising a plurality of nodes, said modes being defined by frequency channels and/or antenna patterns, said wireless network comprising a MAC (Media Access Control) layer and every node comprising at least one MAC queue, comprising the steps of:periodically sending broadcast probe packets by at least one node called transmitter node, using a pre-determined and globally known period and predetermined sequence of transmission modes, each of said probe packets containing the transmission mode used for its transmission a sequence number of the transmission mode in the pre-determined sequence of transmission modes and a timestamp value containing the time said broadcast probe packet was buffered at the MAC queue of the transmitter node; measuring, by at least one second node called receiving node receiving a broadcast probe packet , channel state information of a transmission/reception mode for the link between the transmitter node and the receiving node; storing, by said receiving node, said measured transmission/reception mode for said link; using information contained in said received broadcast probe packet, by said receiving node to determine its reception mode and the beginning and end time instants it will use this reception mode, in order to receive a further broadcast probe packet and measure the next transmission mode of transmitter node, during a next measurement period of transmitter node.

Claims

1. A method for measuring channel state information of multiple communication modes in a multi-mode wireless network comprising a plurality of nodes, the method comprising:

receiving a broadcast probe packet during a measurement period at a first node of said plurality of nodes from a second node of said plurality of nodes using a period and sequence of communication modes, wherein a communication mode is related to a transmission mode or a reception mode for a node of said plurality of nodes and is defined by at least a frequency channel and an antenna pattern, and wherein said broadcast probe packet comprises information including;

(i) an identification of a particular communication mode used for transmission of the broadcast probe packet from the second node;

(ii) a sequence number of the particular communication mode in the sequence of communication modes; and

(iii) a timestamp value representing a time at which said broadcast probe packet was buffered at a MAC queue included in the second node;

measuring, by the first node, channel state information for communication mode used in connecting the second node and the first node;

storing, by said first node, said measured channel state information for the communication mode used in connecting the first and second nodes;

determining, by said first node, the communication mode for the first node using said information in said received broadcast probe packet; and

determining a time during which said first node will use the determined communication mode in order to receive a subsequent broadcast probe packet from said second node during a next measurement period of said second node using said timestamp value from said received broadcast probe packet.

2. The method according to claim 1, wherein the plurality of nodes are capable of transmitting and receiving, wherein said transmitting by a node of the plurality includes transmitting a broadcast probe packet in accordance with a first defined communication mode, and wherein said receiving by a node of the plurality includes receiving, from neighboring nodes of the first node during a measurement period, at least one broadcast probe packet in in accordance with a second defined communication.

3. The method according to claim 1, wherein, at any one time, a node of said plurality of nodes is capable of performing one of:

transmitting the broadcast probe packet in accordance with a communication mode, or receiving the broadcast probe packet in accordance with a communication mode.

4. The method according to claim 1, wherein said channel state information is one of Received Signal Strength or Signal-to-Noise ratio.

5. The method according to claim 1, wherein said second node continuously executes successive measurement rounds, wherein each measurement round consists of M measurement periods, wherein each measurement period lasts TM time units and wherein, at the beginning of the m-th measurement period, an m-th broadcast probe packet is sent to a MAC protocol buffer associated with the second node.

6. The method according to claim 5, wherein, during a measurement period, said second node broadcasts one broadcast probe packet after having switched to the communication mode identified in said broadcast probe packet, and said second node is capable of receiving one or more broadcast probe packets from neighboring nodes of the first node in accordance with one or more different communication modes.

7. The method according to claim 1, wherein the method further includes, in response to receiving a broadcast probe packet at the first node, computing a new start time for receiving in a next measurement period using the timestamp in the broadcast probe packet.

8. The method according to claim 7, wherein the method further includes, determining, by the first node, a receiving duration for the next measurement period by computing:

broadcast probe packet transmission durations for neighboring nodes of the first node,

delay for switching to a communication mode,

a delay factor to account for MAC protocol delay, and

an estimate of a maximum clock phase difference between the first node and the neighboring nodes in the network based on the timestamps in the broadcast probe packets received by the neighboring nodes and maximum propagation delay between the first node and the neighboring nodes.

9. Receiver apparatus in a first node of a multi-mode wireless network comprising a plurality of nodes for measuring channel state information of multiple communication modes, the receiver apparatus including a memory and a processor in communication with said memory;

the processor capable of measuring channel state information of multiple communication modes in said wireless network by;

receiving a broadcast probe packet during a measurement period from a second node of said plurality of nodes using a period and sequence of communication modes, wherein a communication mode is related to a transmission mode or a reception mode for a node of said plurality of nodes and is defined by at least a frequency channel and an antenna pattern, and wherein said broadcast probe packet comprises information including;

(i) an identification of a particular communication mode used for transmission of the broadcast probe packet from the second node;

(ii) a sequence number of the particular communication mode in the sequence of communication modes; and

(iii) a timestamp value representing a time at which said broadcast probe packet was buffered at a MAC queue included in the second node;

measuring channel state information for the communication mode used in connecting the second node and the first node;

storing in the memory said measured channel state information for the communication mode used in connecting the first and second nodes;

determining the communication mode for the first node using said information in said received broadcast probe packet; and

determining a time during which said first node will use the determined communication mode in order to receive a subsequent broadcast probe packet from said second node during a next measurement period of said second node using said timestamp value from said received broadcast probe packet.

10. The receiver apparatus according to claim 9, wherein the plurality of nodes are capable of transmitting and receiving, wherein said transmitting by a node of the plurality includes transmitting a broadcast probe packet in accordance with a first defined communication mode, and wherein said receiving by a node of the plurality includes receiving, from neighboring nodes of the first node during a measurement period, at least one broadcast probe packet in in accordance with a second defined communication mode.

11. The receiver apparatus according to claim 9, wherein, at any one time, a node of said plurality of nodes is capable of performing one of:

transmitting the broadcast probe packet in accordance with a communication mode, or receiving the broadcast probe packet in accordance with a communication mode.

12. The receiver apparatus according to claim 9, wherein said channel state information is one of Received Signal Strength or Signal-to-Noise ratio.

13. The receiver apparatus according to claim 9, wherein said second node continuously executes successive measurement rounds, wherein each measurement round consists of M measurement periods, wherein each measurement period lasts TM time units and wherein, at the beginning of the m-th measurement period, an m-th broadcast probe packet is sent to a MAC protocol buffer associated with the second node.

14. The receiver apparatus according to claim 13, wherein, during a measurement period, said second node broadcasts one broadcast probe packet after having switched to the communication mode identified in said broadcast probe packet, and said second node is capable of receiving one or more broadcast probe packets from neighboring nodes of the first node in accordance with one or more different communication modes.

15. The receiver apparatus according to claim 9, wherein the processor is further capable of measuring by computing, in response to receiving a broadcast probe packet at the first node, a new start time for receiving in a next measurement period using the timestamp in the broadcast probe packet.

16. The receiver apparatus according to claim 15, wherein the processor is further capable of measuring by determining, by the first node, a receiving duration for the next measurement period by computing:

broadcast probe packet transmission durations for neighboring nodes of the first node,

delay for switching to a communication mode,

a delay factor to account for MAC protocol delay, and

an estimate of a maximum clock phase difference between the first node and the neighboring nodes in the network based on the timestamps in the broadcast probe packets received by the neighboring nodes and maximum propagation delay between the first node and the neighboring nodes.

17. Receiver apparatus in a first node of a multi-mode wireless network comprising a plurality of nodes for measuring channel state information of multiple communication modes, the receiver apparatus including an antenna and a processor in communication with said antenna;

the processor capable of measuring channel state information of multiple communication modes in said wireless network by;

receiving, using said antenna, a broadcast probe packet during a measurement period from a second node of said plurality of nodes using a period and sequence of communication modes, wherein a communication mode is related to a transmission mode or a reception mode for a node of said plurality of nodes and is defined by at least a frequency channel and an antenna pattern, and wherein said broadcast probe packet comprises information including;

(i) an identification of a particular communication mode used for transmission of the broadcast probe packet from the second node;

(ii) a sequence number of the particular communication mode in the sequence of communication modes; and

(iii) a timestamp value representing a time at which said broadcast probe packet was buffered at a MAC queue included in the second node;

measuring channel state information for the communication mode used in connecting the second node and the first node;

storing said measured channel state information for the communication mode used in connecting the first and second nodes;

determining the communication mode for the first node using said information in said received broadcast probe packet; and

determining a time during which said first node will use the determined communication mode in order to receive a subsequent broadcast probe packet from said second node during a next measurement period of said second node using said timestamp value from said received broadcast probe packet.

18. The receiver apparatus according to claim 17, wherein the plurality of nodes are capable of transmitting and receiving, wherein said transmitting by a node of the plurality includes transmitting a broadcast probe packet in accordance with a first defined communication mode, and wherein said receiving by a node of the plurality includes receiving, from neighboring nodes of the first node during a measurement period, at least one broadcast probe packet in in accordance with a second defined communication mode.

19. The receiver apparatus according to claim 17, wherein, at any one time, a node of said plurality of nodes is capable of performing one of:

transmitting the broadcast probe packet in accordance with a communication mode, or receiving the broadcast probe packet in accordance with a communication mode.

20. The receiver apparatus according to claim 17, wherein said channel state information is one of Received Signal Strength or Signal-to-Noise ratio.

21. The receiver apparatus according to claim 17, wherein said second node continuously executes successive measurement rounds, wherein each measurement round consists of M measurement periods, wherein each measurement period lasts TM time units and wherein, at the beginning of the m-th measurement period, an m-th broadcast probe packet is sent to a MAC protocol buffer associated with the second node.

22. The receiver apparatus according to claim 21, wherein, during a measurement period, said second node broadcasts one broadcast probe packet after having switched to the communication mode identified in said broadcast probe packet, and said second node is capable of receiving one or more broadcast probe packets from neighboring nodes of the first node in accordance with one or more different communication modes.

23. The receiver apparatus according to claim 17, wherein the processor is further capable of measuring by computing, in response to receiving a broadcast probe packet at the first node, a new start time for receiving in a next measurement period using the timestamp in the broadcast probe packet.

24. The receiver apparatus according to claim 23, wherein the processor is further capable of measuring by determining, by the first node, a receiving duration for the next measurement period by computing:

broadcast probe packet transmission durations for neighboring nodes of the first node,

delay for switching to a communication mode,

a delay factor to account for MAC protocol delay, and

an estimate of a maximum clock phase difference between the first node and the neighboring nodes in the network based on the timestamps in the broadcast probe packets received by the neighboring nodes and maximum propagation delay between the first node and the neighboring nodes.