Apparatus for controlling data transmission timing responsively to a calculated collision ratio

• US 20060050826A1
• Filed: 09/02/2005
• Published: 03/09/2006
• Est. Priority Date: 09/03/2004
• Status: Active Grant

• Current Assignee: OKI Electric Industry Company Limited
• Original Assignee: OKI Electric Industry Company Limited
• Inventors: Date, Masaaki, Kubo, Yuki, Sekiyama, Kosuke
• Granted Patent: US 7,466,685 B2
• Time in Patent Office: Days
• US Class Current: 375/362
• CPC Class Codes: H04J 3/0676 Mutual
• CPC Class Codes: H04W 56/00 Synchronisation arrangements

Abstract

Communication control apparatus provided in nodes forming a telecommunications network includes a transmission timing calculator responsive to the state of the phase of the own node to determine a timing at which the node transmits data. The calculator is responsive to a state variable signal transmitted by a neighboring node and reflecting the phase of the neighboring node to change the state of the phase of the own node in accordance with a time development rule. The calculator monitors a phase difference of the own node against the neighboring node to calculate, based on the difference, the ratio of collision on data transmission timing between the own and neighboring nodes. The stress value corresponding to the collision ratio is stored time-serially. A stress response function value is generated such that the stored stress value causes the time development rule to shift the phase with its value made at random.

Claims

1. Communication control apparatus to be included in a communication node forming a telecommunications network, comprising a transmission timing calculator responsive to a state of a phase changing in an own node for determining a first timing at which the own node transmit data,

wherein said transmission timing calculator comprises:

a phase calculator operative in response to receiving a state variable signal, transmitted by a neighboring node and affected by a phase representative of a second timing at which the neighboring node transmits data, for changing a state of a phase of the own node in accordance with a time development rule;

a collision ratio calculator for monitoring a phase difference of the own node with respect to the neighboring node, and operative in response to the phase difference for calculating a ratio of collision on the first and second timings; and

a stress response function value generator for storing time-serially a stress value corresponding to the ratio of collision, and operative in response to the stored stress value for causing the time development rule to provide a phase shift with a value of the phase shift made at random.

2. The apparatus in accordance with claim 1, wherein the time development rule defines a phase response function having a dynamic characteristic changing, when a relative phase difference between the own and neighboring nodes does not exceed a phase width required for avoiding collision, the phase of the own node with respect to the phase of the neighboring node in a direction effecting a repulsion force.

3. The apparatus in accordance with claim 1, wherein said collision ratio calculator monitors an amount of collision accumulated in a predetermined period of time, the ratio of collision being equal to a value resultant from normalizing the accumulated amount of collision with a maximum accumulated amount of collision.

4. The apparatus in accordance with claim 1, wherein said stress response function value generator calculates the stress value on a basis of a function having a characteristic increasing a value as the ratio of collision increases.

5. The apparatus in accordance with claim 3, wherein the period of time continues from a previous time at which the phase shift was performed with the value of the phase shift made at random to a present time.

6. The apparatus in accordance with claim 1, wherein said stress response function value generator evaluates the stored stress value at a predetermined time interval to produce an evaluated value, and causes the time development to provide the phase shift at a probability based upon the evaluated value.

7. The apparatus in accordance with claim 1, further comprising an impulse signal transmitter and receiver for transmitting a first impulse signal serving as the state variable signal at a discrete fashion at a timing dependent upon the phase of the own node, and for receiving a second impulse signal transmitted by the neighboring node to cause the phase of the neighboring node to be available to said phase calculator.

8. The apparatus in accordance with claim 1, further comprising a phase signal transmitter and receiver for consecutively transmitting a continuous phase signal serving as a phase variable signal affected by the phase of the own node, and for receiving a phase signal transmitted by the neighboring node to cause the phase of the neighboring node to be available to said phase calculator.

9. The apparatus in accordance with claim 8, wherein the phase signal is transmitted in a first frequency band different from a second frequency band in which a data signal is transmitted, the first frequency band comprising a plurality of frequency subbands,

said apparatus further comprising an arbitrator for performing an initial operation of transmitting and receiving the phase signal to and from the neighboring node to arbitrate the frequency subbands available to the own and neighboring nodes.

10. A method of controlling communication in a communication node forming a telecommunications network, comprising the step of calculating a transmission timing in response to a state of a phase changing in an own node to determine a first timing at which the own node transmit data,

said step of calculating the transmission timing comprising the substeps of:

changing, in response to receiving a state variable signal, transmitted by a neighboring node and affected by a phase representative of a second timing at which the neighboring node transmits data, a state of a phase of the own node in accordance with a time development rule to calculate a phase;

monitoring a phase difference of the own node with respect to the neighboring node, and calculating, in response to the phase difference, a ratio of collision on the first and second timings; and

storing time-serially a stress value corresponding to the ratio of collision, and causing, in response to the stored stress value, the time development rule to provide a phase shift with a value of the phase shift made at random to generate a stress response function value.

11. Communication control apparatus to be included in a communication node forming a telecommunications network, comprising a transmission timing calculator responsive to a state of a phase changing in an own node for determining a first timing at which the own node transmit data,

wherein said transmission timing calculator comprises:

a phase calculator operative in response to receiving a state variable signal, transmitted by a neighboring node and affected by a phase representative of a second timing at which the neighboring node transmits data, for changing a state of a phase of the own node in accordance with a time development rule based upon a phase response function;

a collision ratio calculator for monitoring a phase difference of the own node with respect to the neighboring node, and operative in response to the phase difference for calculating a ratio of collision on the first and second timings; and

a phase response function characteristic determiner operative in response to the ratio of collision for changing a characteristic of the phase response function.

12. The apparatus in accordance with claim 11, wherein said phase response function characteristic determiner provides, when the ratio of collision is larger, the phase response function with a characteristic appropriate for reducing the ratio of collision, and changes the characteristic appropriately for equalizing a distribution of a phase difference as a value of the ratio of collision gets smaller.

13. The apparatus in accordance with claim 11, wherein said transmission timing calculator further comprises a stress response function value generator for storing time-serially a stress value corresponding to the ratio of collision, and operative in response to the stored stress value for causing the time development rule to provide a phase shift with a value of the phase shift made at random.

14. The apparatus in accordance with claim 13, wherein said stress response function value generator and said phase response function characteristic determiner are operative, when the value of the ratio of collision is smaller, by providing the phase response function with a characteristic appropriate for reducing the ratio of collision, and cause, in response to the stored stress value, the time development rule to provide a phase shift with a value of the phase shift made at random,

said stress response function value generator and said phase response function characteristic determiner working the phase response function operative, as the ratio of collision gets smaller, by changing the characteristic appropriately for equalizing a distribution of a phase difference.

15. The apparatus in accordance with claim 12, wherein said phase response function characteristic determiner adjusts the phase difference equally to a predetermined phase width, the predetermined phase width corresponding to a duration of one of a plurality of time segments into which one period is equally divided,

said phase response function characteristic determiner having a dynamic characteristic of changing, when the value of the ratio of collision where a relative phase difference does not exceed the predetermined phase width is larger, a phase of the own node with respect to a phase of the neighboring node in a direction effecting a repulsion force,

said phase response function characteristic determiner changing, as the ratio of collision gets smaller, the characteristic of the phase response function to a dynamic characteristic of bringing the phase difference close to an integral multiple of the predetermined phase width.

16. A method of controlling communication in a communication node forming a telecommunications network, comprising the step of calculating a transmission timing in response to a state of a phase changing in an own node to determine a first timing at which the own node transmit data,

said step of calculating the transmission timing comprising the substeps of:

changing, in response to receiving a state variable signal, transmitted by a neighboring node and affected by a phase representative of a second timing at which the neighboring node transmits data, a state of a phase of the own node in accordance with a time development rule based upon a phase response function to calculate a phase;

monitoring a phase difference of the own node with respect to the neighboring node, and calculating, in response to the phase difference, a ratio of collision on the first and second timings; and

changing, in response to the ratio of collision, a characteristic of the phase response function to determine a phase response function characteristic.

17. A communication node forming a telecommunications network and including communication control apparatus comprising a transmission timing calculator responsive to a state of a phase changing in an own node for determining a first timing at which the own node transmit data,

wherein said transmission timing calculator comprises:

a phase calculator operative in response to receiving a state variable signal, transmitted by a neighboring node and affected by a phase representative of a second timing at which the neighboring node transmits data, for changing a state of a phase of the own node in accordance with a time development rule;

a collision ratio calculator for monitoring a phase difference of the own node with respect to the neighboring node, and operative in response to the phase difference for calculating a ratio of collision on the first and second timings; and

a stress response function value generator for storing time-serially a stress value corresponding to the ratio of collision, and operative in response to the stored stress value for causing the time development rule to provide a phase shift with a value of the phase shift made at random.

18. A telecommunications system including a plurality of communication nodes, each of the plurality of communication nodes including communication control apparatus comprising a transmission timing calculator responsive to a state of a phase changing in an own node for determining a first timing at which the own node transmit data,

wherein said transmission timing calculator comprises:

a phase calculator operative in response to receiving a state variable signal, transmitted by a neighboring node and affected by a phase representative of a second timing at which the neighboring node transmits data, for changing a state of a phase of the own node in accordance with a time development rule;

a collision ratio calculator for monitoring a phase difference of the own node with respect to the neighboring node, and operative in response to the phase difference for calculating a ratio of collision on the first and second timings; and

a stress response function value generator for storing time-serially a stress value corresponding to the ratio of collision, and operative in response to the stored stress value for causing the time development rule to provide a phase shift with a value of the phase shift made at random.