Transmission quality reporting

• US 6,477,355 B1
• Filed: 03/25/1999
• Issued: 11/05/2002
• Est. Priority Date: 04/30/1998
• Status: Expired due to Term

• Current Assignee: DBSD Services Ltd. (Dish Network Corporation)
• Original Assignee: ICO Services, Ltd. (Dish Network Corporation)
• Inventors: Grayson, Mark, Mullins, Dennis Roy
• Primary Examiner(s): Le, Thanh Cong
• Assistant Examiner(s): LE, LANA N
• Application Number:
  US09/275,891
• Time in Patent Office: 1,321 Days
• Field of Search: 455/69, 455/502, 455/67.1, 455/423, 455/425, 455/13.4, 455/12.1
• US Class Current: 455/13.4
• CPC Class Codes: H04B 17/24 with feedback of measurements to the transmitter
• CPC Class Codes: H04B 17/309 Measuring or estimating channel quality parameters
• 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: H04L 1/20 using signal quality detector
• CPC Class Codes: H04W 52/20 using error rate

Abstract

In a satellite mobile telecommunication system, TDMF traffic is transmitted from a SAN 1 via a satellite 3 to a mobile user terminal UT1, over a duplex link 1, 2. The SAN 1 instructs the satellite 3a to transmit signals over link 1 to UT 1 at a power level dependent upon the quality of signal received by UT 1, so as to adaptively control the power to an efficient level. Similarly, the power level of signals transmitted by UT 1 to the satellite is controlled depending on the error rate. The power level required is computed as a function of the average of easured areas determined during a given measurement period together with a margin which is computed as an adaptive function of a deviation of the errors bout the average value.

Claims

1. A user terminal for a radio telecommunications system, comprising:

measuring circuitry operable to provide respective measured values of a quality metric of wanted radio signals received by the terminal during a given measurement period,

an averager to produce an average of the values of the quality metric,

a processor to provide a deviation signal with a value as a function of a deviation between the average of the values of the quality metric and at least one of said measured values which adopts a predetermined value relationship with the average, in respect of the measurement period, and

a transmitter to report the average value and the value of the deviation signal to a location remote from the user terminal.

2. A user terminal according to claim 1 wherein said one of the measured values comprises the measured value which deviates the most from the average value during the measurement period.

3. A user terminal according to claim 1 wherein the quality metric comprises a frame error rate in successive samples of the received radio signals.

4. A user terminal according to claim 1 wherein the quality metric comprises a bit error rate in successive samples of the received radio signals.

5. A user terminal according to claim 1 including setting circuitry responsive to a setting signal received from the remote location for setting a transmission characteristic of signals transmitted thereby in accordance with the setting signal.

6. A subsystem for use in a radio telecommunications system to communicate with remote user terminals, comprising:

a receiver to receive from a remote user terminal data corresponding to an average of measured values of a quality metric for wanted radio signals received by the terminal during a given measurement period, and a deviation signal corresponding to a deviation between the average of the values of the quality metric and at least one of the measured values for the measurement period, and

a processor operable to produce a set value of a transmission characteristic for radio signals transmitted to the user terminal as a function of both the average of the quality metric and a margin selected as a function of said deviation.

7. A subsystem according to claim 6 including a processor to produce a signal corresponding to said set value of said transmission characteristic, and a transmitter operable to transmit said signal to a remote location to control transmission therefrom.

8. A subsystem according to claim 6, comprising a ground station for a satellite telecommunications system, wherein said signal is transmitted towards a satellite for controlling a transmission characteristic thereof.

9. A subsystem according to claim 6, comprising a base station subsystem for a terrestrial telecommunications system, wherein said signal is transmitted towards the remote user terminal for controlling a transmission characteristic thereof.

10. A subsystem according to claim 6 wherein the transmission characteristic comprises transmitted power level.

11. A method of operating a user terminal for a radio telecommunications system, comprising:

determining respective measured values of a quality metric of wanted radio signals received by the terminal during a given measurement period,

computing an average of the values of the quality metric,

determining a deviation between the average of the values of the quality metric and at least one of the measured values for the measurement period, and

reporting the average value and the deviation to a location remote from the user terminal.

12. A method of operating a subsystem for use in a radio telecommunications system to communicate with remote user terminals, comprising:

receiving from a remote user terminal, data corresponding to an average of the values of a quality metric for radio signals received by the terminal during a given measurement period, and a deviation between the average and at least one of the measured values of the quality metric for the measurement period, and

producing a set value of a transmission characteristic for radio signals transmitted to the user terminal as a function of both the average of the quality metric and a margin selected as a function of said deviation.

13. A method according to claim 12 including forming a setting signal corresponding to the set value and transmitting the setting signal towards the remote user terminal.

14. A method according to claim 13 including transmitting the setting signal towards an earth orbiting satellite to set the power level of signals transmitted thereby to the remote user terminal.

15. A method according to claim 13 including transmitting the setting signal towards an earth orbiting satellite to set the power level of signals transmitted thereto by the remote user terminal.

16. A method according to claim 14 including encoding the setting signal in a TCH/SACCH.