Method for performing packet flooding at wireless ad hoc network

• US 7,266,386 B2
• Filed: 04/06/2004
• Issued: 09/04/2007
• Est. Priority Date: 04/30/2003
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Myung-jong, Zhu, Chun-hui, Kim, Ji-tae
• Primary Examiner(s): NGUYEN, THUAN T
• Application Number:
  US10/817,926
• Publication Number:
  US 20040218557A1
• Time in Patent Office: 1,246 Days
• Field of Search: 455/445, 455/446, 455/447, 455/448, 455/449, 455/452.1, 455/453, 4551271-1275, 455/522, 370/237, 370/328, 370/338, 370/238
• US Class Current: 455/522
• CPC Class Codes: H04W 52/343 taking into account loading or congestion level
• CPC Class Codes: H04W 52/346 distributing total power among users or channels
• CPC Class Codes: H04W 52/36 with a discrete range or set of values, e.g. step size, ramping or offsets
• CPC Class Codes: H04W 52/48 during retransmission after error or non-acknowledgment
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method for packet re-flooding in a wireless ad hoc network for transmitting a broadcast packet from a source node to a destination node. In order to determine the respective nodes received with the broadcast packet from the source node into a certain number of power levels in accordance with the receiving power of the signal carrying the received packet, the packet re-flooding method includes the steps of setting a power level reference by which the power level increases as the receiving power increases, obtaining the receiving power of the signal carrying the packet received from the respective nodes but not the source node, determining power levels based on the power level reference and the obtained receiving power, calculating a back-off delay time in accordance with the power levels of the respective nodes but not the source node, and re-flooding the received packet when the calculated back-off delay time of the respective nodes excluding the source node expires and when the received packet is the first packet that is received. Accordingly, the possibility of having collisions due to re-flooding of the respective nodes is reduced, and also, overall power consumption of the network decreases.

Claims

1. A method for performing packet re-flooding in a wireless ad hoc network including a plurality of nodes, comprising:

establishing a power level reference so that each of the plurality of nodes, other than a source node, receiving a broadcast packet from the source node is assigned a predetermined number of power levels corresponding to a receiving power of a signal carrying the received packet;

each of the plurality of nodes, except the source node, obtaining the receiving power of the signal carrying the received packet, respectively;

establishing one of the power levels as a respective power level of each of the plurality of nodes based on the power level reference, in accordance with the receiving power as obtained;

calculating a back-off delay time in accordance with the power level established for each of the plurality of nodes, except the source node; and

when the back-off delay time of a respective one of the plurality of nodes, except the source node, expires, and the received packet is not identical to a packet previously received by the respective one of the plurality of nodes, the respective one of the plurality of nodes re-floods the received packet.

2. The packet re-flooding method of claim 1, wherein the step of establishing the power level reference comprises:

obtaining a transmission power of the source node, and a minimum acceptable receiving power of each of the plurality of nodes, except the source node;

calculating a distance between a denary logarithmic value of the transmission power of the source node and a denary logarithmic value of the maximum acceptable receiving power of the each of the plurality of nodes except the source node; and

calculating a range of the power level reference by dividing the calculated distance by the number of power levels, and setting the power level reference in accordance with the calculated range of the power level reference.

3. The packet re-flooding method of claim 1, wherein the step of establishing one of the power levels comprises:

obtaining a minimum acceptable receiving power of each of the plurality of nodes, except the source node; and

obtaining a difference by subtracting a denary logarithmic value of the minimum acceptable receiving power from a denary logarithmic value of the receiving power of each of the plurality of nodes except the source node, dividing the difference by a logarithmic value of a number of power levels, and determining the power level of the plurality of nodes except the source node based on the resultant value of the division and the established power level reference.

4. The packet re-flooding method of claim 1, wherein the back-off delay time calculating step comprises:

obtaining a size of the received packet from each of the plurality of nodes except the source node, and also a maximum transmission capacity of each of the plurality of nodes;

calculating a packet transmission time by dividing the size of the packet of each of the plurality of nodes except the source node, by the maximum transmission capacity; and

calculating the back-off delay time by obtaining a difference of subtracting 1 from the established power levels and multiplying the difference by the calculated packet transmission time and a number greater than 1.

5. A method for performing packet re-flooding in a wireless ad hoc network including a plurality of nodes, comprising:

establishing a power level reference so that each of the plurality of nodes, other than a source node, receiving a broadcast packet from the source node is assigned a predetermined number of power levels corresponding to a receiving power of a signal carrying the received packet;

each of the plurality of nodes, except the source node, obtaining the receiving power of the signal carrying the received packet, respectively;

establishing one of the power levels as a respective power level of each of the plurality of nodes based on the power level reference, in accordance with the receiving power as obtained;

calculating a back-off delay time in accordance with the power level established for each of the plurality of nodes, except the source node; and

when the back-off delay time of a respective one of plurality of nodes, except the source node, expires, and the received packet is not identical to a packet previously received by the respective one of the plurality of nodes, the respective one of the plurality of nodes re-floods the received packet only if the respective one of the plurality of nodes is the node having a lowest power level of the plurality of nodes.

6. A method for performing packet re-flooding in a wireless ad hoc network including a plurality of nodes, comprising:

establishing a power level reference so that each of the plurality of nodes, other than a source node, receiving a broadcast packet from the source node is assigned a predetermined number of power levels corresponding to a receiving power of a signal carrying the received packet;

each of the plurality of nodes, except the source node, obtaining the receiving power of the signal carrying the received packet, respectively;

establishing one of the power levels as a respective power level of each of the plurality of nodes based on the power level reference, in accordance with the receiving power as obtained;

calculating a back-off delay time in accordance with the power level established for each of the plurality of nodes, except the source node; and

when the back-off delay time of a respective one of the plurality of nodes, except the source node, expires, and when the receiving power of the respective one of the plurality of nodes is equal to, or smaller than a predetermined threshold, the respective one of the plurality of nodes re-floods the received packet.

7. A method for performing packet re-flooding in a wireless ad hoc network including a plurality of nodes, comprising:

establishing a power level reference so that each of the plurality of nodes, other than a source node, receiving a broadcast packet from the source node is assigned a predetermined number of power levels corresponding to a receiving power of a signal carrying the received packet;

each of the plurality of nodes, except the source node, obtaining the receiving power of the signal carrying the received packet, respectively;

establishing one of the power levels as a respective power level of each of the plurality of nodes based on the power level reference, in accordance with the receiving power as obtained;

calculating a back-off delay time in accordance with the power level established for each of the plurality of nodes, except the source node; and

when the back-off delay time of a respective one of the plurality of nodes, except the source node, expires, and the received packet is not identical to a packet previously received by the respective one of the plurality of nodes, the respective one of the plurality of nodes re-floods the received packet, except that when the respective node receives a packet that is re-flooded by one of the plurality of nodes other than the source node and when the receiving power of the signal carrying the received packet is equal to, or smaller than a predetermined threshold, the respective one of the plurality of nodes re-floods the received packet even when the received packet is identical to the packet previously received.

8. A method for performing packet re-flooding in a wireless ad hoc network including a plurality of nodes, comprising:

establishing a power level reference so that each of the plurality of nodes, other than a source node, receiving a broadcast packet from the source node is assigned a predetermined number of power levels corresponding to a receiving power of a signal carrying the received packet;

each of the plurality of nodes, except the source node, obtaining the receiving power of the signal carrying the received packet, respectively;

establishing one of the power levels as a respective power level of each of the plurality of nodes based on the power level reference, in accordance with the receiving power as obtained;

calculating a back-off delay time in accordance with the power level established for each of the plurality of nodes, except the source node; and

when the back-off delay time of a respective one of the plurality of nodes, except the source node, expires, and the received packet is not identical to a packet previously received by the respective one of the plurality of nodes, the respective one of the plurality of nodes re-floods the received packet, except that when the respective one of the plurality of nodes receives a packet which is re-flooded by at least two of the plurality of nodes but not the source node, the respective one of the plurality of nodes re-floods the received packet even when the received packet is identical to the packet previously received.