1. A blade outer air seal for a gas turbine engine, comprising:
an arcuate first seal segment that extends circumferentially to a first confronting face; and
an arcuate second seal segment that extends circumferentially to a second confronting face;
wherein the first confronting face is positioned adjacent the second confronting face defining a gap therebetween;
wherein the confronting faces are radially non-parallel at a first engine operating point where each seal segment has a first temperature distribution profile and a first pressure distribution profile; and
wherein the confronting faces are substantially radially parallel at a second engine operating point where each seal segment has a second temperature distribution profile and a second pressure distribution profile, which first temperature distribution profile is different than the second temperature distribution profile, and which first pressure distribution profile is different than the second pressure distribution profile.
2. The blade outer air seal of claim 1, wherein a minimum gap width is defined circumferentially between the first and the second confronting faces, which minimum gap width is larger at the first engine operating point than at the second engine operating point.
3. The blade outer air seal of claim 1, wherein:
an inner gap width is defined circumferentially between radially inner ends of the confronting faces;
an outer gap width is defined circumferentially between radially outer ends of the confronting faces; and
the inner gap width is greater than the outer gap width at the first engine operating point.
4. The blade outer air seal of claim 1, wherein the first confronting face has a substantially linear cross-sectional geometry at the first engine operating point.
5. The blade outer air seal of claim 4, wherein the first confronting face extends between a radially outer end and a radially inner end, which outer end extends circumferentially beyond the inner end at the first engine operating point such that the first confronting face is skewed, via an offset angle, relative to the second confronting face.
6. The blade outer air seal of claim 5, wherein the first confronting face comprises outer surfaces of a pair of axially extending rails that define a groove therebetween.
7. A blade outer air seal for a gas turbine engine, comprising:
an arcuate first seal segment that extends circumferentially to a first confronting face; and
an arcuate second seal segment that extends circumferentially to a second confronting face;
wherein the first confronting face is positioned adjacent the second confronting face defining a gap therebetween;
wherein the gap varies radially at a first engine operating point where each seal segment has a first temperature distribution profile and a first pressure distribution profile; and
wherein the gap is substantially radially uniform at a second engine operating point where each seal segment has a second temperature distribution profile and a second pressure distribution profile, which first temperature distribution profile is different than the second temperature distribution profile, and which first pressure distribution profile is different than the second pressure distribution profile.
8. The blade outer air seal of claim 7, wherein a minimum gap width is defined circumferentially between the first and the second confronting faces, which minimum gap width is larger at the first engine operating point than at the second engine operating point.
9. The blade outer air seal of claim 7, wherein:
an inner gap width is defined circumferentially between radially inner ends of the confronting faces;
an outer gap width is defined circumferentially between radially outer ends of the confronting faces; and
the inner gap width is greater than the outer gap width at the first engine operating point.
10. The blade outer air seal of claim 7, wherein the first confronting face has a substantially linear cross-sectional geometry at the first engine operating point.
11. The blade outer air seal of claim 10, wherein the first confronting face extends between a radially outer end and a radially inner end, which outer end extends circumferentially beyond the inner end at the first engine operating point such that the first confronting face is skewed, via an offset angle, relative to the second confronting face.
12. The blade outer air seal of claim 11, wherein the first confronting face comprises outer surfaces of a pair of axially extending rails that define a groove therebetween.
13. A blade outer air seal for a gas turbine engine, comprising:
an arcuate first seal segment that extends circumferentially to a first confronting face; and
an arcuate second seal segment that extends circumferentially to a second confronting face;
wherein the first confronting face is positioned adjacent the second confronting face defining a gap therebetween, which gap has a radially inner gap width and a radially outer gap width;
wherein the inner gap width is greater than the outer gap width at a first engine operating point where each seal segment has a first temperature distribution profile and a first pressure distribution profile; and
wherein the inner gap width is substantially equal to the outer gap width at a second engine operating point where each seal segment has a second temperature distribution profile and a second pressure distribution profile, which first temperature distribution profile is different than the second temperature distribution profile, and which first pressure distribution profile is different than the second pressure distribution profile.
14. The blade outer air seal of claim 13, wherein:
the inner gap width extends circumferentially between radially inner ends of the confronting faces; and
the outer gap width extends circumferentially between radially outer ends of the confronting faces.
15. The blade outer air seal of claim 13, wherein a minimum gap width is defined circumferentially between the first and the second confronting faces, which minimum gap width is larger at the first engine operating point than at the second engine operating point.
16. The blade outer air seal of claim 13, wherein the first confronting face has a substantially linear cross-sectional geometry at the first engine operating point.
17. The blade outer air seal of claim 16, wherein the first confronting face extends between a radially outer end and a radially inner end, which outer end extends circumferentially beyond the inner end at the first engine operating point such that the first confronting face is skewed, via an offset angle, relative to the second confronting face.
18. The blade outer air seal of claim 17, wherein the first confronting face comprises outer surfaces of a pair of axially extending rails that define a groove therebetween.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of wireless communication, comprising:
identifying a state transition of a compressor side of a robust header compression (RoHC) protocol to an initialization and refresh (IR) state;
identifying that a payload of at least part of a media frame is to be transmitted in the IR state; and
dropping at least part of the payload when a probability of segmenting the payload during transmission in the IR state exceeds a threshold.
2. The method of claim 1, wherein the probability of segmenting the payload is based at least in part on a predetermined number of protocol data units (PDUs) exceeding a PDU count threshold.
3. The method of claim 1, wherein the probability of segmenting the payload is based at least in part on resources available for the transmission of a RoHC header and the payload.
4. The method of claim 3, wherein the resources comprise one or more of:
an amount of uplink resources assigned in an uplink grant;
an amount of downlink resources available for the transmission; or
a modulation and coding scheme to be used for the transmission.
5. The method of claim 3, wherein the probability of segmenting the payload is based at least in part on a power headroom value.
6. The method of claim 1, wherein the probability of segmenting the payload is based at least in part on one or more of:
a channel condition of an radio frequency (RF) channel used for the transmission;
a Sounding Reference Signal (SRS) measurement;
a distance from a receiver of the transmission; or
a pathloss from the receiver of the transmission.
7. The method of claim 1, wherein the identifying the transition of RoHC to the IR state comprises one or more of:
identifying a handover condition;
identifying an media frame error rate; or
identifying a Block Error Rate exceeding a threshold.
8. The method of claim 1, wherein the dropping at least part of the payload comprises:
dropping a predetermined number of protocol data units (PDUs).
9. The method of claim 8, wherein the predetermined number of PDUs is based at least in part on a data type of the payload.
10. The method of claim 8, wherein the predetermined number of PDUs is based at least in part on the segmentation of the payload exceeding a certain number of PDUs.
11. The method of claim 1, wherein the dropping at least part of the payload comprises:
determining an amount of available resources for transmission;
determining a combined size of a complete header and the payload; and
dropping a portion of the payload that exceeds a difference between the combined size and the amount of available resources.
12. The method of claim 11, wherein dropping at least part of the payload comprises
dropping least significant bit(s) of the payload that exceed the difference between the combined size and the amount of available resources.
13. A method of wireless communication, comprising:
determining that a combined size of a first robust header compression (RoHC) header and a first payload to be transmitted with the first RoHC header exceed a predetermined threshold;
dropping at least part of the first payload, responsive to the determining, to keep the combined size less than the predetermined threshold;
determining that a second combined size of a second RoHC header and a second payload to be transmitted with the second RoHC header exceed the predetermined threshold;
dropping at least part of the second payload to generate a modified second payload; and
transmitting the second RoHC header and modified second payload in place of the payload.
14. The method of claim 13, wherein the dropping comprises dropping a contiguous part of the first or second payload.
15. The method of claim 13, wherein the dropped part of the first or second payload is unrecoverable.
16. The method of claim 13, wherein the predetermined threshold is determined based on:
an amount of available resources for transmission;
a size of the first or the second RoHC header; and
a size of the first or the second payload.
17. The method of claim 16, wherein the dropping at least part of the first or second payload comprises:
dropping a portion of the first or second payload that exceeds a difference between the combined size of the respective RoHC header and the respective payload, and the amount of available resources.
18. The method of claim 13, wherein dropping at least part of the payload comprises:
dropping one or more least significant bit(s) of the payload that exceed a difference between the combined size of the RoHC header and the payload, and an amount of available resources.
19. An apparatus for wireless communication, comprising:
means for identifying a state transition of a robust header compression (RoHC) mode to an initialization and refresh (IR) state;
means for identifying that a payload of at least part of a media frame is to be transmitted in the IR state; and
means for dropping at least part of the payload when a probability of segmenting the payload during transmission in the IR state exceeds a threshold.
20. The apparatus of claim 19, wherein the probability of segmenting the payload is based at least in part on a grant condition.
21. The apparatus of claim 20, wherein the grant condition comprises one or more of an amount of uplink resources assigned in an uplink grant or a modulation and coding scheme of the uplink grant.
22. The apparatus of claim 20, wherein the probability of segmenting the payload is based at least in part on one or more of:
a predetermined number of protocol data units (PDUs) exceeding a PDU threshold;
a power headroom index value;
a channel condition of an radio frequency (RF) channel used for the transmission;
a distance from a receiver of the transmission; or
a pathloss from the receiver of the transmission.
23. The apparatus of claim 19, wherein the means for identifying the transition of RoHC to the IR state identifies one or more of a handover condition, a media frame error rate, or a Block Error Rate exceeding a threshold.
24. The apparatus of claim 19, wherein the means for dropping at least part of the payload:
determines an available uplink capacity for an uplink grant;
determines a combined size of a complete header and the payload; and
drops a portion of the payload that exceeds a difference between the combined size and the available uplink capacity.
25. An apparatus for wireless communication, comprising:
a processor;
memory in electronic communication with the processor, the memory embodying instructions, the instructions being executable by the processor to:
identify a state transition of a robust header compression (RoHC) mode to an initialization and refresh (IR) state;
identify that a payload of at least part of a media frame is to be transmitted in the IR state; and
drop at least part of the payload when a probability of segmenting the payload during transmission in the IR state exceeds a threshold.
26. The apparatus of claim 25, wherein the probability of segmenting the payload is based at least in part on one or more of:
a predetermined number of protocol data units (PDUs) exceeding a PDU threshold;
a grant condition;
a channel condition of an radio frequency (RF) channel used for the transmission;
a distance from a receiver of the transmission; or
a pathloss from the receiver of the transmission.
27. The apparatus of claim 25, wherein the instructions are further executable by the processor to identify one or more of a handover condition, a media frame error rate, or a Block Error Rate exceeding a threshold.
28. The apparatus of claim 25, wherein the instructions are further executable by the processor to:
determine an available uplink capacity for an uplink grant;
determine a combined size of a complete header and the payload; and
drop a portion of the payload that exceeds a difference between the combined size and the available uplink capacity.