System for improved power savings during full DTX mode of operation in the downlink

• US 20030086381A1
• Filed: 10/18/2002
• Published: 05/08/2003
• Est. Priority Date: 10/19/2001
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Terry, Stephen E., DiFazio, Robert A.
• Granted Patent: US 7,768,953 B2
• Time in Patent Office: Days
• US Class Current: 370/280
• CPC Class Codes: H04B 2201/70709 with discontinuous detection
• CPC Class Codes: H04B 7/2618 using hybrid code-time division multiple access [CDMA-TDMA]
• CPC Class Codes: H04B 7/2643 using time-division multiple access [TDMA] H04B7/2615, H04B7/2618 take precedence
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04W 52/0216 using a pre-established activity schedule, e.g. traffic indication frame
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A system and method that achieve power savings by turning off all or some of the baseband processing for codes and timeslots that have not been transmitted due to full DTX. When full DTX is detected by reception of a Special Burst (SB), the receiver is turned off for all timeslots and frames for the duration of the Special Burst Scheduling Period (SBSP). The transmitter schedules transmissions following any idle period to start on the boundary of the SBSP. The receiver determines the SBSP and if the transmitter initiates transmissions according to SBSP by reception of several initial full DTX cycles.

Claims

1. A method for handling the transmission of data during discontinuous transmission (DTX) in a TDD;

comprising;

a) monitoring each TTI for data to transmit;

b) determining whether there is data to transmit in the TTI, and if so, proceeding to step c; and

if not, proceeding to step d;

c) processing the data and returning to step a;

d) recording the connection frame number;

e) setting an idle scheduling period;

f) turning off receiver processing during said idle period;

g) buffering any data to transmit during said idle period.

2. The method of claim 1 further comprising:

h) turning on receiver processing at the end of said idle period.

3. The method of claim 1 further comprising:

i) determining, at the end of said idle period, whether there is any buffered data to transmit.

4. The method of claim 3, whereby if said determination in step 1 is positive, returning to step c.

5. The method of claim 3, whereby if said determination in step i is negative, returning to step d.

6. The method of claim 1 wherein said buffering step g further comprises:

g1) determining the Quality of Service (QoS) requirements for said data to transmit during said buffering period.

7. The method of claim 6 wherein said buffering step g further comprises:

g2) determining whether the QoS requirements permit buffering of said data during said idle period, and if so, buffering said data to transmit during said idle period;

whereby, if the QoS requirements do not permit buffering of said data during said idle period, proceeding to step c.

8. A method for determining the Special Burst Scheduling Period (SBSP) during discontinuous transmission (DTX) in a TDD system;

comprising;

a) receiving a TFCI for a coded composite transport channel (CCTrCH);

b) determining if the received TFCI is a Special Burst (SB);

whereby if it is not an SB, proceeding to step a, and if it is an SB, proceeding to step c;

c) initializing a timing value;

d) incrementing said value by the duration of said TTI;

e) reading the next TFCI at the beginning of the next TTI;

f) determining whether said next TFCI is an SB;

whereby if it is not an SB, proceeding to step d, and if it is an SB, proceeding to step g; and

g) storing said timing value as the SBSP.

9. The method of claim 8 further comprising:

h) repeating steps c-g.

10. A method for determining the scheduling of data during discontinuous transmission (DTX) in a TDD system having a Special Burst Scheduling Period (SBSP);

comprising;

a) initializing an intelligent scheduling parameter (ISP)

b) receiving a TFCI for a coded composite transport channel (CCTrCH);

c) determining if the received TFCI is a Special Burst (SB);

whereby if it is not an SB, proceeding to step b, and if it is an SB, proceeding to step d;

d) reading the next TFCI at the beginning of the next TTI;

e) determining the TFCI is valid;

whereby if it is not a valid TFCI, proceeding to step d, and if it is a valid TFCI, proceeding to step f;

f) determining whether said valid TFCI is an SB;

whereby if it is an SB, proceeding to step d, and if it is not an SB, proceeding to step g; and

g) determining the number of frames that have passed, and whether the number of frames equals the SBSP;

whereby if it is not equal, decrementing the ISP, and if it is equal, incrementing the ISP.

11. The method of claim 10 further comprising:

h) setting an ISP threshold.

12. The method of claim 11 further comprising:

i) comparing said ISP to said threshold, and if said ISP exceeds said threshold, declaring that intelligent scheduling is performed.

13. A method for handling the transmission of data during discontinuous transmission (DTX) in a TDD;

comprising;

a) receiving a TFCI for a coded composite transport channel (CCTrCH);

b) determining if the received TFCI is a Special Burst (SB);

whereby if it is not an SB, proceeding to step c, and if it is an SB, proceeding to step d;

c) processing the data and returning to step a;

d) turning off receiver processing;

e) turning on receiver processing at the start of predetermined duration;

f) reading the TFCI;

g) determining if the received TFCI is a Special Burst (SB);

whereby if it is not an SB, proceeding to step c, and if it is an SB, proceeding to step d.

14. A TDD system for saving power during discontinuous transmission (DTX);

comprising;

a preprocessing unit for determining whether a received signal includes a valid TFCI;

a detection unit for reading the valid TFCI to determine if it is a special burst (SB);

a learning unit for determining when data will be transmitted, and for turning on and off receiver processing for all codes and timeslots that will not be used.

15. The system of claim 14, wherein said preprocessing unit further comprises:

a code power estimation unit for estimating the power of the received signal.

16. The system of claim 15, wherein said preprocessing unit further comprises a burst quality estimation unit for estimating the quality of the received signal.

17. The system of claim 14, wherein said detection unit further comprises an end of DTX detection unit for reading said valid TFCI and identifying whether data is being transmitted.

18. The system of claim 17, wherein said detection unit further comprises a special burst detection unit for reading said valid TFCI and identifying whether it is a special burst indicating full DTX.

19. A method for handling the transmission of data during discontinuous transmission (DTX) in a TDD;

comprising;

a) determining whether there is data to transmit in a TTI, and if so, proceeding to step b; and

if not, proceeding to step c;

c) processing the data and returning to step a;

d) setting an idle scheduling period;

e) turning off receiver processing during said idle period;

f) buffering any data to transmit during said idle period.

20. The method of claim 19 further comprising:

g) turning on receiver processing at the end of said idle period.

21. A method for determining the Special Burst Scheduling Period (SBSP) during discontinuous transmission (DTX) in a TDD system;

comprising;

a) determining if a received TFCI is a Special Burst (SB);

whereby if it is not an SB, repeating step a, and if it is an SB, proceeding to step b;

b) setting a value;

c) incrementing said value by the duration of said TTI;

d) reading the next TFCI at the beginning of the next TTI;

e) determining whether said next TFCI is an SB;

whereby if it is not an SB, proceeding to step c, and if it is an SB, proceeding to step f; and

f) storing said timing value as the SBSP.

22. A method for determining the Special Burst Scheduling Period (SBSP) during discontinuous transmission (DTX) in a TDD system;

comprising;

a) determining if a received TFCI is a Special Burst (SB);

whereby if it is not an SB, repeating step a, and if it is an SB, proceeding to step b;

b) initializing a timing value;

c) incrementing said value by the duration of said TTI;

d) determining whether the next TFCI at the beginning of the next TTI is an SB;

whereby if it is not an SB, proceeding to step c, and if it is an SB, proceeding to step e; and

e) storing said timing value as the SBSP.

23. A method for determining the scheduling of data during discontinuous transmission (DTX) in a TDD system having a Special Burst Scheduling Period (SBSP);

comprising;

a) initializing an intelligent scheduling parameter (ISP)

b) determining if a received TFCI is a Special Burst (SB);

whereby if it is not an SB, proceeding to step a, and if it is an SB, proceeding to step c;

c) determining if the next TFCI in the next TTI is valid;

whereby if it is not a valid TFCI, repeating step c, and if it is a valid TFCI, proceeding to step d;

d) determining whether said valid TFCI is an SB;

whereby if it is an SB, proceeding to step c, and if it is not an SB, proceeding to step e; and

g) determining the number of frames that have passed, and whether the number of frames equals the SBSP;

whereby if it is not equal, decrementing the ISP, and if it is equal, incrementing the ISP.