Apparatus, systems and methods for improved link quality evaluation of mobile cellular systems

• US 9,596,638 B2
• Filed: 09/30/2015
• Issued: 03/14/2017
• Est. Priority Date: 02/11/2015
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Damji, Navid, Makharia, Shivesh, Verger, Luciano M., Khay-Ibbat, Samy, Sebeni, Johnson O., Kodali, Sree Ram, Vallath, Sreevalsan
• Primary Examiner(s): NGUYEN, KHAI MINH
• Application Number:
  US14/871,493
• Publication Number:
  US 20160234750A1
• Time in Patent Office: 531 Days
• Field of Search: 455/67.11, 455/436, 455/67.14, 455/550.1
• US Class Current: 1/1
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0036 arrangements specific to the receiver
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/203 Details of error rate determination, e.g. BER, FER or WER
• CPC Class Codes: H04W 28/22 Negotiating communication rate
• CPC Class Codes: H04W 36/00226 wherein the core network technologies comprise IP multimedia system [IMS], e.g. single radio voice call continuity [SRVCC]
• CPC Class Codes: H04W 36/144 over a different radio air interface technology
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Apparatus, system and methods for evaluating link quality within a cellular system. A user equipment (“UE”) is connected to a network, wherein the UE communicates data to the network on an uplink (“UL”) link. The UE determines a requested buffer size for a UL communication, determines a transport block size for the UL communication based on a primary set of allocation parameters, and compares the requested buffer size to the transport block size to determine if a data rate for the UL communication satisfies a threshold. When the data rate satisfies the threshold, the UE identifies the UL link as a good quality link and sends acceptable link quality feedback to the network. When the data rate does not satisfy the threshold, the UE performs a further action to test a quality of the UL link.

Claims

1. A method, comprising:

at a user equipment (“

UE”

) connected to a network, wherein the UE communicates data to the network on an uplink (“

UL”

) link;

determining a requested buffer size for a UL communication;

determining a transport block size for the UL communication based on a primary set of allocation parameters;

comparing the requested buffer size to the transport block size to determine a data rate for the UL communication that is being supported by the network;

determining when the data rate for the UL communication satisfies a threshold;

when the data rate satisfies the threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the data rate does not satisfy the threshold, performing a further action to test a quality of the UL link.

2. The method of claim 1, wherein the primary set of allocation parameters includes at least one of a modulation and coding scheme (“

MCS”

) and a resource block allocation.

3. The method of claim 1, wherein the further action includes:

determining when a transmit power value satisfies a transmit power threshold;

when the transmit power value satisfies the transmit power threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the transmit power value does not satisfy the transmit power threshold, identifying the UL link as a poor quality link and sending poor link quality feedback to the network.

4. The method of claim 1, wherein the further action includes:

determining when a power headroom value satisfies a power headroom threshold;

when the power headroom value satisfies the power headroom threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the power headroom value does not satisfy the power headroom threshold, identifying the UL link as a poor quality link and sending poor link quality feedback to the network.

5. The method of claim 1, wherein the further action includes:

determining when a hybrid automatic repeat request (“

HARQ”

) retransmission rate satisfies a HARQ retransmission rate threshold;

when the HARQ retransmission satisfies the HARQ retransmission threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the HARQ retransmission does not satisfy the HARQ retransmission threshold, identifying the UL link as a poor quality link and sending poor link quality feedback to the network.

6. The method of claim 1, further comprising:

filtering the primary set of allocation parameters using one of a finite impulse response (“

FIR”

) filter and an infinite impulse response (“

IIR”

) filter.

7. The method of claim 1, further comprising:

identifying the UL link as a poor quality link; and

performing at least one of;

lowering an audio codec rate used on the UL link,

selecting a different UL link associated with a different radio access technology (“

RAT”

), and

triggering a hand-over to a neighboring node.

8. A user equipment (“

UE”

) connected to a network via an uplink (“

UL”

) link, comprising;

a processor configured to control establishing and releasing connections between the UE and a first wireless network and between the UE and a second wireless network;

a transceiver configurable to transmit and receive signals to the first wireless network according to a first wireless communication protocol and to the second wireless network according to a second wireless communication protocol; and

a non-transitory memory having a program stored thereon, wherein execution of the program causes the processor to perform operations comprising;

determining a requested buffer size for a UL communication;

determining a transport block size for the UL communication based on a primary set of allocation parameters;

comparing the requested buffer size to the transport block size to determine a data rate for the UL communication that is being supported by the network;

determining when the data rate for the UL communication satisfies a threshold;

when the data rate satisfies the threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the data rate does not satisfy the threshold, performing a further action to test a quality of the UL link.

9. The UE of claim 8, wherein the primary set of allocation parameters includes at least one of a modulation and coding scheme (“

MCS”

) and a resource block allocation.

10. The UE of claim 8, wherein the further action includes:

determining when a transmit power value satisfies a transmit power threshold;

when the transmit power value satisfies the transmit power threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the transmit power value does not satisfy the transmit power threshold, identifying the UL link as a poor quality link and sending poor link quality feedback to the network.

11. The UE of claim 8, wherein the further action includes:

determining when a power headroom value satisfies a power headroom threshold;

when the power headroom value satisfies the power headroom threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the power headroom value does not satisfy the power headroom threshold, identifying the UL link as a poor quality link and sending poor link quality feedback to the network.

12. The UE of claim 8, wherein the further action includes:

determining when a hybrid automatic repeat request (“

HARQ”

) retransmission rate satisfies a HARQ retransmission rate threshold;

when the HARQ retransmission satisfies the HARQ retransmission threshold, identifying the UL link as a good quality link and sending acceptable link quality feedback to the network; and

when the HARQ retransmission does not satisfy the HARQ retransmission threshold, identifying the UL link as a poor quality link and sending poor link quality feedback to the network.

13. The UE of claim 8, wherein the operations further comprise:

filtering the primary set of allocation parameters using one of a finite impulse response (“

FIR”

) filter and an infinite impulse response (“

IIR”

) filter.

14. The UE of claim 8, wherein the operations further comprise:

identifying the UL link as a poor quality link; and

performing at least one of;

lowering an audio codec rate used on the UL link,

selecting a different UL link associated with a different radio access technology (“

RAT”

), and

triggering a hand-over to a neighboring node.

15. A method, comprising:

at a user equipment (“

UE”

);

comparing a first channel quality factor determined at the UE to a first threshold value, wherein the UE is connected to a network and communicates with the network on a link;

when the first channel quality factor satisfies the first threshold, identifying the link as a good quality link and sending acceptable link quality feedback to the network;

when the first channel quality factor does not satisfy the first threshold, comparing a further channel quality factor determined at the UE to a further threshold value;

when the further channel quality factor satisfies the further threshold, identifying the link as a good quality link and sending acceptable link quality feedback to the network; and

when the further channel quality factor does not satisfy the further threshold, performing a further action to test a quality of the UL link.

16. The method of claim 15, wherein the first channel quality factor includes at least one of a modulation and coding scheme (“

MCS”

) and a resource block allocation.

17. The method of claim 15, wherein the further channel quality factor includes at least one of a transmit power value, power headroom value, and a hybrid automatic repeat request (“

HARQ”

) retransmission rate.

18. The method of claim 15, wherein the further action includes:

comparing an additional channel quality factor determined at the UE to an additional threshold value;

when the additional channel quality factor satisfies the additional threshold, identifying the link as a good quality link and sending acceptable link quality feedback to the network; and

when the additional channel quality factor does not satisfy the additional threshold, identifying the link as a poor quality link and sending poor link quality feedback to the network.

19. The method of claim 15, further comprising:

filtering the first channel quality factor using one of a finite impulse response (“

FIR”

) filter and an infinite impulse response (“

IIR”

) filter.

20. The method of claim 15, further comprising:

identifying the UL link as a poor quality link; and

performing at least one of;

lowering an audio codec rate used on the UL link,

selecting a different UL link associated with a different radio access technology (“

RAT”

), and

triggering a hand-over to a neighboring node.