Multi-Dimensional Adaptive Transmission Technique

• US 20120149299A1
• Filed: 02/21/2012
• Published: 06/14/2012
• Est. Priority Date: 12/18/2007
• Status: Active Grant

• Current Assignee: Gilat Satellite Networks Limited
• Original Assignee: Gilat Satellite Networks Limited
• Inventors: Laish, Isacc Ben, Tamam, Ronen, Pinchas, Magal
• Granted Patent: US 8,588,842 B2
• Time in Patent Office: Days
• US Class Current: 455/9
• CPC Class Codes: H04B 7/18513 Transmission in a satellite or space-based system
• CPC Class Codes: H04B 7/18519 Operations control, administration or maintenance
• CPC Class Codes: H04B 7/18543 for adaptation of transmission parameters, e.g. power control for detecting or preventing errors in the information received H04L1/00
• CPC Class Codes: H04B 7/18573 for operations control, administration or maintenance
• CPC Class Codes: H04B 7/18597 Arrangements for system physical machines management, i.e. for construction, operations control, administration, maintenance
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

Method and apparatus for dynamically optimizing the transmission level of each remote terminal in a satellite-based communication network. Each remote terminal maintains quasi-error-free communication at the highest efficiency level available under changing link conditions and network configurations, without requiring the reservation of substantial power margins, which results in a much more efficient satellite network.

Claims

1. A method of performing a log on procedure to a satellite-based communication network, comprising:

determining, at a remote terminal in the satellite-based communication network, an initial transmit power level based on a predefined value;

transmitting, from the remote terminal, a plurality of logon messages at the initial transmit power level to a hub in the satellite-based communication network;

determining whether one or more acknowledgements are received for the plurality of logon messages transmitted at the initial transmit power level;

when determining that no acknowledgements were received for the plurality of logon messages transmitted at the initial transmit power level, determining an increased transmit power level greater than the initial transmit power level;

transmitting, from the remote terminal, a second plurality of logon messages to the hub at the increased transmit power level;

determining whether one or more acknowledgements are received for the plurality of logon messages transmitted at the increased transmit power level;

when determining that one or more acknowledgements were received for the plurality of logon messages transmitted at the increased transmit power level, configuring the remote terminal for communication with the hub based on the increased transmit power level.

2. The method of claim 1, further comprising:

determining a triggering condition for performing the log on procedure, wherein determining the triggering condition comprises one or more of;

detecting an installation of the remote terminal;

detecting an updated configuration of the remote terminal;

or

detecting a hardware change at the remote terminal.

3. The method of claim 2, further comprising:

detecting a hardware change at the remote terminal, the detected hardware change comprising one or more of;

replacement of an indoor unit at the remote terminal;

replacement of a satellite transmitter at the remote terminal;

or

redeployment of cables connecting an indoor unit and a satellite transmitter at the remote terminal.

4. The method of claim 1, further comprising:

upon determining the triggering condition for performing the log on procedure, erasing a previously stored transmit power range and a previously stored maximal transmit power level.

5. A method, comprising:

(a) transmitting, from a remote terminal in a satellite-based communication network, a plurality of maintenance packets to a hub at a first transmit power level;

(b) receiving, at the remote terminal, one or more reply packets containing reception level measurements for one or more of the maintenance packets transmitted at the first transmit power level;

(c) calculating a first average reception level for the maintenance packets transmitted at the first transmit power level;

(d) calculating a first gain equivalent value based on the first average reception level at the first transmit power level and a determined first satellite transmitter input power level;

(e) repeating steps (a)-(d) for a second transmit power level greater than the first transmit power level, calculating a second gain equivalent value based on a second average reception level at the second transmit power level and a determined second satellite transmitter input power level;

(f) comparing a difference between the first gain equivalent and the second gain equivalent to a predetermined gain difference threshold; and

(g) when the difference between the first gain equivalent and the second gain equivalent exceeds the predetermined gain difference threshold, calculating and storing at the remote terminal a maximal transmit power level based on one or more of the first transmit power level and the second transmit power level.

6. The method of claim 5, wherein the predetermined gain difference threshold corresponds to an approximately 1 dB compression point between the first gain equivalent and the second gain equivalent.

7. The method of claim 5, wherein the maximal transmit power level is set to the first transmit power level.

8. The method of claim 5, further comprising:

(h) when the difference between the first gain equivalent and the second gain equivalent does not exceed the predetermined gain difference threshold, repeating steps (a)-(d) for a third transmit power level greater than the second transmit power level, calculating a third gain equivalent value based on a third average reception level at the third transmit power level and a determined third satellite transmitter input power level.

9. A method, comprising:

determining, by a remote terminal in a satellite-based communication network, a first transmit power level for transmitting maintenance packets to a hub in the satellite-based communication network;

determining a maximal transmit power level for transmitting data to the hub;

transmitting one or more maintenance packets to the hub, wherein each maintenance packet is configured to include an information item containing a difference between the first transmit power level for transmitting the maintenance packets and the maximal transmit power for transmitting data to the hub;

receiving, at the remote terminal, one or more reply packets corresponding to the one or more maintenance packets, each said reply packet containing a measured reception level of its corresponding maintenance packet by the hub; and

adjusting, at the remote terminal, one or more transmit power levels for transmitting data to the hub based on the received measured reception levels in the reply packets.

10. The method of claim 9, wherein transmitting the maintenance packets to the hub comprises determining one or more transmission timeslots allocated by the hub to the remote terminal.

11. The method of claim 9, wherein adjusting the one or more transmit power levels for transmitting data to the hub comprises:

determining a decline in the measured reception level of the maintenance packets by the hub; and

configuring the remote terminal to increase its transmit power level up to a maximal transmit power level.

12. The method of claim 11, wherein the maximal transmit power level is based on one or more of:

capabilities of an indoor unit of the remote terminal;

or

a maximal output power at a maximal transmit power point of a satellite transmitter of the remote terminal.

13. A method, comprising:

receiving, at a hub in a satellite-based communication network, maintenance packets from a plurality of remote terminals;

measuring the reception level of the maintenance packets received from the plurality of remote terminals;

identifying a plurality of different timeslot types in a return link of the satellite-based communication network, wherein each of the plurality of remote terminals are associated with one or more of the different timeslot types; and

based on the measured reception levels of the maintenance packets, reconfiguring the distribution of allocations of the plurality of remote terminals to the plurality of different timeslot types.

14. The method of claim 13, wherein each of the different timeslot types corresponds to a different combination of a symbol rate and a modulation and coding combination.

15. The method of claim 13, wherein measuring the reception level of the maintenance packets comprises:

retrieving an information item from a first received maintenance packet sent by a first remote terminal, the information item corresponding to a delta value between the transmit power of the first maintenance packet and a maximal transmit power of the first remote terminal; and

using the delta value, calculating a first maximal reception level for data received by the hub from the first remote terminal.

16. The method of claim 15, wherein reconfiguring the distribution of allocations of the plurality of remote terminals to the different timeslot types comprises:

determining an efficient timeslot type for the first remote terminal based on the first maximal reception level.

17. The method of claim 16, wherein determining the efficient timeslot type for the first remote terminal comprises:

determining a lack of timeslots of a most efficient timeslot type for the first remote terminal; and

assigning one or more less efficient timeslot types to the first remote terminal, based on a determination that a nominal reception level for the one or more less efficient timeslot types is below the maximal reception level of the remote terminal.

18. The method of claim 13, further comprising:

for a first maintenance packet received at the hub from a first remote terminal, transmitting a reply packet to the first remote terminal containing the measured reception level of the first maintenance packet.

19. The method of claim 18, wherein transmitting the reply packet for the first maintenance packet comprises configuring the reply packet to be transmitted as part of a Correction Message Table (CMT).

20. The method of claim 18, wherein transmitting the reply packet for the first maintenance packet comprises configuring the reply packet to be transmitted as part of a correction message descriptor included in a unicast Terminal Information Message (TIM).