1. A method for forming a bi-layered carpet underlay suitable for installation between a subfloor and a carpet, the method comprising:
forming a homogeneous blend of fibers comprised of carrier fibers and binder fibers, said binder fibers comprising between about five percent by volume and about fifty percent by volume of said homogeneous blend of fibers;
forming a non-woven fiber batt from said homogeneous blend of fibers, wherein formation of said non-woven fiber batt comprises bonding binder fibers to each other and to carrier fibers, said non-woven fiber batt having a surface;
providing a cured layer of re-bonded foam particles, said cured layer of re-bonded foam particles having a surface;
applying an adhesive to said surface of said non-woven fiber batt or to said surface of said cured layer of re-bonded foam particles;
disposing said surface of said non-woven fiber batt with said surface of said cured layer of re-bonded foam particles; and
bonding said surface of said non-woven fiber batt to said surface of said cured layer of re-bonded foam particles to form a bi-layered carpet underlay.
2. The method of claim 1 wherein said non-woven fiber batt comprises synthetic fibers.
3. The method of claim 1 wherein providing a cured layer of re-bonded foam particles comprises providing a cured layer of re-bonded foam particles selected from the group consisting of recycled ether foams, ester foams, mattress quilting material foams, automobile headliner and door panel foams, and carpet underlay foams.
4. The method of claim 3 wherein of said non-woven fiber batt comprises synthetic fibers.
5. The method of claim 1 wherein bonding said surface of said non-woven fiber batt to said surface of said cured layer of foam particles further comprises:
compressing said surfaces together to form the bond between said non-woven fiber batt and said cured layer of re-bonded foam particles.
6. The method of claim 5 wherein the adhesive applied to said surface of said non-woven fiber batt or to said surface of said cured layer of re-bonded foam is a heat activated adhesive and wherein the bonding of said non-woven fiber batt and said cured layer of re-bonded foam particles further comprises:
heating said non-woven fiber batt and said cured layer of re-bounded foam to cure the adhesive and form the bond between said surface of said non-woven fiber batt and said surface of said cured layer of re-bonded foam particles.
7. The method of claim 6 wherein providing a cured layer of re-bonded foam particles comprises providing a cured layer of re-bonded foam particles selected from the group consisting of recycled ether foams, ester foams, mattress quilting material foams, automobile headliner and door panel foams, and carpet underlay foams.
8. The method of claim 1, wherein providing a cured layer of re-bonded foam particles further comprises:
forming a cured block of re-bonded foam particles; and
slicing said cured block of re-bonded foam particles into a plurality of cured layers of re-bonded foam particles.
9. The method of claim 8, wherein forming a cured block of re-bonded foam particles further comprises forming said cured block of re-bonded particles from shredded recycled foam.
10. The method of claim 1, wherein said homogeneous blend of fibers includes between about 15% and about 40% by volume of binder fibers and wherein said non-woven fiber batt is a densified batt.
11. The method of claim 1, wherein said non-woven fiber batt is a densified batt having a ratio of ounces per square foot to thickness in inches of at least about 2:1.
12. The method of claim 1, wherein said non-woven fiber batt is a densified batt having a density of at least about 1.5 pounds per cubic foot.
13. The method of claim 1, wherein said non-woven fiber batt is a high loft batt having a ratio of ounces per square foot to thickness in inches of less than about 2:1.
14. The method of claim 13 wherein said non-woven fiber batt has a thickness in a range which extends from about \xbc inch to about \xbd inch and wherein providing a cured layer of re-bonded foam particles comprises providing a cured layer of re-bonded particles having a thickness in a range which extends from about \xbc inch to about \xbd inch.
15. The method of claim 14 wherein said non-woven fiber batt comprises synthetic fibers and wherein providing a cured layer of re-bonded particles having a thickness in a range which extends from about \xbc inch to about \xbd inch comprises providing a cured layer of re-bonded particles having a thickness in a range which extends from about \xbc inch to about \xbd inch and selected from the group consisting of recycled ether foams, ester foams, mattress quilting material foams, automobile headliner and door panel foams, and carpet underlay foams.
16. The method of claim 1, wherein said non-woven fiber batt is a high loft batt having a density of less than about 1.5 pounds per cubic foot.
17. A method for forming a bi-layered carpet underlay suitable for installation between a subfloor and a carpet, the method comprising:
forming a homogeneous blend of fibers comprised of carrier fibers and binder fibers, said binder fibers comprising between about fifteen percent by volume and about forty percent by volume of said homogeneous blend of fibers;
forming a densified non-woven fiber batt from said homogeneous blend of fibers, wherein formation of said non-woven fiber batt comprises bonding binder fibers to each other and to carrier fibers, said non-woven fiber batt having a surface and having a density of at least 1.5 pounds per cubic foot and a ratio of ounces per square foot to thickness in inches of at least 2:1;
providing a cured layer of re-bonded foam particles, said cured layer of re-bonded foam particles having a surface;
providing a film having first and second surfaces and an adhesive on both of said surfaces of said film;
disposing said non-woven fiber batt, said cured layer of re-bonded foam particles, and film together with said film positioned between said non-woven fiber batt and said cured layer of re-bonded foam particles; and
compressing said non-woven fiber batt, said cured layer of re-bonded foam particles, and film to bond said adhesive on said first surface of said film to said surface of said non-woven fiber batt and to bond said adhesive on said second surface of said film to said surface of said cured layer of re-bonded foam particles to form the carpet underlay.
18. The method of claim 17 wherein providing a cured layer of re-bonded foam particles comprises providing a cured layer of re-bonded foam particles selected from the group consisting of recycled ether foams, ester foams, mattress quilting material foams, automobile headliner and door panel foams, and carpet underlay foams.
19. The method of claim 18 wherein said non-woven fiber batt comprises synthetic fibers.
20. The method of claim 17, wherein providing a cured layer of re-bonded foam particles further comprises:
forming a cured block of re-bonded foam particles; and
slicing said cured block of re-bonded foam particles into a plurality of cured layers of re-bonded foam particles.
21. The method of claim 20, wherein forming a cured block of re-bonded foam particles further comprises forming said cured block of re-bonded particles from shredded recycled foam.
22. A method for forming a bi-layered carpet underlay, comprising:
forming a homogeneous blend of fibers comprised of (1) shoddy material containing recycled fibers from both natural and synthetic materials, and (2) binder fibers, said binder fibers comprising between about five percent by volume and about fifty percent by volume of said homogeneous blend of fibers;
forming a non-woven fiber batt from said homogeneous blend of fibers, wherein formation of said non-woven fiber batt comprises bonding binder fibers to each other and to shoddy material;
providing a cured layer of re-bonded foam particles, said cured layer of re-bonded foam particles having a surface;
applying an adhesive to a surface of said non-woven fiber batt or to said surface of said cured layer of re-bonded foam particles;
disposing said surface of said non-woven fiber batt with said surface of said cured layer of re-bonded foam particles; and
bonding said surface of said non-woven fiber batt to said surface of said cured layer of re-bonded foam particles to form the bi-layered carpet underlay.
23. The method of claim 22, wherein said homogeneous blend of fibers is between about fifteen percent, by volume and about forty percent, by volume, of binder fibers.
24. The method of claim 23, wherein said non-woven fiber batt is a densified fiber batt having a density of at least 1.5 pounds per cubic foot and a ratio of ounces per square foot to thickness in inches of at least 2:1.
25. The method of claim 22, wherein said non-woven fiber batt is a high loft fiber batt having a ratio of ounces per square foot to thickness in inches of less than 2:1 and a density of less than about 1.5 pounds per cubic foot.
26. A method for forming a bi-layered carpet underlay, comprising:
forming a homogeneous blend of plural types of fibers which include hollow carrier fibers, solid carrier fibers and binder fibers, said binder fibers comprising between about five percent, by volume, and about fifty percent, by volume of said homogeneous blend of fibers;
forming a non-woven fiber batt from said homogeneous blend of fibers, said non-woven fiber batt having a surface, wherein formation of said non-woven fiber batt comprises bonding binder fibers to each other and to carrier fibers;
providing a cured layer of re-bonded foam particles, said cured layer of re-bonded foam particles having a surface;
applying an adhesive to said surface of said non-woven fiber batt or to said surface of said cured layer of re-bonded foam particles;
disposing said surface of said non-woven fiber batt with said surface of said cured layer of re-bonded foam particles; and
bonding said surface of said non-woven fiber batt to said surface of said cured layer of re-bonded foam particles.
27. The method of claim 26, wherein said homogeneous blend of fibers is between about fifteen percent, by volume and about forty percent, by volume, of binder fibers.
28. The method of claim 27, wherein said non-woven fiber batt is a densified fiber batt having a density of at least 1.5 pounds per cubic foot and a ratio of ounces per square foot to thickness in inches of at least 2:1.
29. The method of claim 26, wherein said non-woven fiber batt is a high loft fiber batt having a ratio of ounces per square foot to thickness in inches of less than 2:1 and a density of less than about 1.5 pounds per cubic foot.
30. A method for forming a bi-layered carpet underlay, comprising:
forming a homogeneous blend of binder fibers and hollow, solid and crimped carrier fibers of varying diameters and deniers, said binder fibers comprising between about five percent, by volume, and about fifty percent, by volume of said homogeneous blend of fibers;
forming a non-woven fiber batt from said homogeneous blend of fibers, said non-woven fiber batt having a surface, wherein formation of said non-woven fiber batt comprises bonding binder fibers to each other and to carrier fibers;
providing a cured layer of re-bonded foam particles, said cured layer of re-bonded foam particles having a surface;
applying an adhesive to said surface of said non-woven fiber batt or to said surface of said cured layer of re-bonded foam particles;
disposing said surface of said non-woven fiber batt with said surface of said cured layer of re-bonded foam particles; and
bonding said surface of said non-woven fiber batt to said surface of said cured layer of re-bonded foam particles to form the bi-layered carpet underlay.
31. The method of claim 30, wherein forming a homogeneous blend of binder fibers and hollow, solid and crimped carrier fibers of varying diameters and deniers comprises forming a homogeneous blend of binder fibers and hollow, solid and crimped synthetic and natural carrier fibers of varying diameters and deniers.
32. The method of claim 31, and further comprising:
selecting one or more synthetic fiber from the group consisting of polyester, nylon and polypropylene fibers;
selecting one or more natural fiber from the group consisting of cotton, wool, camel, llama and cashmere fibers; and
blending said selected synthetic and natural fibers together.
33. The method of claim 30, wherein said homogeneous blend of fibers is between about fifteen percent, by volume and about forty percent, by volume, of binder fibers.
34. The method of claim 33, wherein said non-woven fiber batt is a densified fiber batt having a density of at least 1.5 pounds per cubic foot and a ratio of ounces per square foot to thickness in inches of at least 2:1.
35. The method of claim 30, wherein said non-woven fiber batt is a high loft fiber batt having a ratio of ounces per square foot to thickness in inches of less than 2:1 and a density of less than about 1.5 pounds per cubic foot.
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:
receiving, at a base station, feedback from a user equipment (UE), wherein the feedback is related to one or more reference signals;
obtaining, at the base station, a tilt adjustment based, at least in part, on the feedback;
generating an elevation precoding vector based, at least in part, on the feedback; and
performing elevation beamforming with an antenna array of the base station for the UE using the tilt adjustment and elevation precoding vector.
2. The method of claim 1, wherein the receiving the feedback includes:
receiving, at the base station, uplink reference signals from the UE; and
obtaining downlink channel matrices of the UE based on the uplink reference signals.
3. The method of claim 2, wherein the obtaining the tilt adjustment includes estimating a downtilt angle associated with the UE using the downlink channel matrices.
4. The method of claim 3, further including:
transmitting, from the base station, a reference signal of the one or more reference signals using the tilt adjustment, wherein the receiving the feedback further includes receiving precoding information from the UE related to the reference signal.
5. The method of claim 1, wherein the one or more reference signals include a reference signal transmitted at an initial tilt adjustment, wherein the receiving the feedback includes:
receiving precoding information from the UE related to the reference signal; and
receiving a tilt update from the UE based on the reference signal.
6. The method of claim 5, wherein the tilt update includes one of:
a fixed tilt adjustment indicator; and
a selectable tilt adjustment selected by the UE.
7. The method of claim 5, further comprising:
adjusting the initial tilt adjustment using the tilt update.
8. The method of claim 1, wherein the one or more reference signals include a predetermined plurality of orthogonal reference signals, wherein each of the predetermined plurality of orthogonal reference signals is transmitted using an associated tilt adjustment, wherein the receiving the feedback includes:
receiving precoding information and measurement information from the UE for each of the predetermined plurality of orthogonal reference signals.
9. The method of claim 8, wherein the obtaining the tilt adjustment includes:
identifying the associated tilt adjustment related to one of the predetermined plurality of orthogonal reference signals having a best link quality based on the measurement information received from the UE.
10. The method of claim 9, further including:
transmitting, from the base station, a reference signal of the one or more reference signals using the tilt adjustment.
11. The method of claim 1, wherein the feedback received from the UE is based on a first number, E, of antenna ports visible to the UE while the elevation beamforming performed by the base station uses a second number, M, of physical antenna elements, wherein M>>E.
12. The method of claim 1, wherein the antenna array is a two-dimensional array of a first number, N, of subarrays, in which each of the N subarrays includes a second number, E, of antenna ports mapped to a third number, M, of physical elements, wherein the performing the elevation beamforming includes applying the tilt adjustment and the elevation precoding vector to each of the N subarrays separately.
13. An apparatus configured for wireless communication, comprising:
means for receiving, at a base station, feedback from a user equipment (UE), wherein the feedback is related to one or more reference signals;
means for obtaining, at the base station, a tilt adjustment based, at least in part, on the feedback;
means for generating an elevation precoding vector based, at least in part, on the feedback; and
means for performing elevation beamforming with an antenna array of the base station for the UE using the tilt adjustment and elevation precoding vector.
14. The apparatus of claim 13, wherein the means for receiving the feedback include:
means for receiving, at the base station, uplink reference signals from the UE; and
means for obtaining downlink channel matrices of the UE based on the uplink reference signals.
15. The apparatus of claim 14, wherein the means for obtaining the tilt adjustment include means for estimating a downtilt angle associated with the UE using the downlink channel matrices.
16. The apparatus of claim 15, further including:
means for transmitting, from the base station, a reference signal of the one or more reference signals using the tilt adjustment, wherein the means for receiving the feedback further include means for receiving precoding information from the UE related to the reference signal.
17. The apparatus of claim 13, wherein the one or more reference signals include a reference signal transmitted at an initial tilt adjustment, wherein the means for receiving the feedback include:
means for receiving precoding information from the UE related to the reference signal; and
means for receiving a tilt update from the UE based on the reference signal.
18. The apparatus of claim 17, wherein the tilt update includes one of:
a fixed tilt adjustment indicator; and
a selectable tilt adjustment selected by the UE.
19. The apparatus of claim 17, further comprising:
means for adjusting the initial tilt adjustment using the tilt update.
20. The apparatus of claim 13, wherein the one or more reference signals include a predetermined plurality of orthogonal reference signals, wherein each of the predetermined plurality of orthogonal reference signals is transmitted using an associated tilt adjustment, wherein the means for receiving the feedback include:
means for receiving precoding information and measurement information from the UE for each of the predetermined plurality of orthogonal reference signals.
21. The apparatus of claim 20, wherein the means for obtaining the tilt adjustment include:
means for identifying the associated tilt adjustment related to one of the predetermined plurality of orthogonal reference signals having a best link quality based on the measurement information received from the UE.
22. The apparatus of claim 21, further including:
means for transmitting, from the base station, a reference signal of the one or more reference signals using the tilt adjustment.
23. The apparatus of claim 13, wherein the feedback received from the UE is based on a first number, E, of antenna ports visible to the UE while the elevation beamforming performed by the base station uses a second number, M, of physical antenna elements, wherein M>>E.
24. The apparatus of claim 13, wherein the antenna array is a two-dimensional array of a first number, N, of subarrays, in which each of the N subarrays includes a second number, E, of antenna ports mapped to a third number, M, of physical elements,
wherein the means for performing the elevation beamforming include means for applying the tilt adjustment and the elevation precoding vector to each of the N subarrays separately.
25. A computer program product for wireless communications in a wireless network, comprising:
a non-transitory computer-readable medium having program code recorded thereon, the program code including:
program code for causing a computer to receive, at a base station, feedback from a user equipment (UE), wherein the feedback is related to one or more reference signals;
program code for causing the computer to obtain, at the base station, a tilt adjustment based, at least in part, on the feedback;
program code for causing the computer to generate an elevation precoding vector based, at least in part, on the feedback; and
program code for causing the computer to perform elevation beamforming with an antenna array of the base station for the UE using the tilt adjustment and elevation precoding vector.
26. The computer program product of claim 25, wherein the program code for causing the computer to receive the feedback includes program code for causing the computer to:
receive, at the base station, uplink reference signals from the UE; and
obtain downlink channel matrices of the UE based on the uplink reference signals.
27. The computer program product of claim 26, wherein the program code for causing the computer to obtain the tilt adjustment includes program code for causing the computer to estimate a downtilt angle associated with the UE using the downlink channel matrices.
28. The computer program product of claim 27, further including:
program code for causing the computer to transmit, from the base station, a reference signal of the one or more reference signals using the tilt adjustment, wherein the program code for causing the computer to receive the feedback further includes program code for causing the computer to receive precoding information from the UE related to the reference signal.
29. The computer program product of claim 25, wherein the one or more reference signals include a reference signal transmitted at an initial tilt adjustment, wherein the program code for causing the computer to receive the feedback includes program code for causing the computer to:
receive precoding information from the UE related to the reference signal; and
receive a tilt update from the UE based on the reference signal.
30. The computer program product of claim 25, wherein the one or more reference signals include a predetermined plurality of orthogonal reference signals, wherein each of the predetermined plurality of orthogonal reference signals is transmitted using an associated tilt adjustment, wherein the program code for causing the computer to receive the feedback includes program code for causing the computer to receive precoding information and measurement information from the UE for each of the predetermined plurality of orthogonal reference signals.
31. The computer program product of claim 30, wherein the program code for causing the computer to obtain the tilt adjustment includes program code for causing the computer to identify the associated tilt adjustment related to one of the predetermined plurality of orthogonal reference signals having a best link quality based on the measurement information received from the UE.
32. The computer program product of claim 25, wherein the antenna array is a two-dimensional array of a first number, N, of subarrays, in which each of the N subarrays includes a second number, E, of antenna ports mapped to a third number, M, of physical elements,
wherein the program code for causing the computer to perform the elevation beamforming includes program code for causing the computer to apply the tilt adjustment and the elevation precoding vector to each of the N subarrays separately.
33. An apparatus configured for wireless communication, the apparatus comprising:
at least one processor; and
a memory coupled to the at least one processor,
wherein the at least one processor is configured:
to receive, at a base station, feedback from a user equipment (UE), wherein the feedback is related to one or more reference signals;
to obtain, at the base station, a tilt adjustment based, at least in part, on the feedback;
to generate an elevation precoding vector based, at least in part, on the feedback; and
to perform elevation beamforming with an antenna array of the base station for the UE using the tilt adjustment and elevation precoding vector.
34. The apparatus of claim 33, wherein the configuration of the at least one processor to receive the feedback includes configuration to:
receive, at the base station, uplink reference signals from the UE; and
obtain downlink channel matrices of the UE based on the uplink reference signals.
35. The apparatus of claim 34, wherein the configuration of the at least one processor to obtain the tilt adjustment includes configuration to estimate a downtilt angle associated with the UE using the downlink channel matrices.
36. The apparatus of claim 35, further including:
configuration of the at least one processor to transmit, from the base station, a reference signal of the one or more reference signals using the tilt adjustment, wherein the configuration of the at least one processor to receive the feedback further includes configuration to receive precoding information from the UE related to the reference signal.
37. The apparatus of claim 33, wherein the one or more reference signals include a reference signal transmitted at an initial tilt adjustment, wherein the configuration of the at least one processor to receive the feedback includes configuration to:
receive precoding information from the UE related to the reference signal; and
receive a tilt update from the UE based on the reference signal.
38. The apparatus of claim 33, wherein the one or more reference signals include a predetermined plurality of orthogonal reference signals, wherein each of the predetermined plurality of orthogonal reference signals is transmitted using an associated tilt adjustment, wherein the configuration of the at least one processor to receive the feedback includes configuration to receive precoding information and measurement information from the UE for each of the predetermined plurality of orthogonal reference signals.
39. The apparatus of claim 38, wherein the configuration of the at least one processor to obtain the tilt adjustment includes configuration to identify the associated tilt adjustment related to one of the predetermined plurality of orthogonal reference signals having a best link quality based on the measurement information received from the UE.
40. The apparatus of claim 33, wherein the antenna array is a two-dimensional array of a first number, N, of subarrays, in which each of the N subarrays includes a second number, E, of antenna ports mapped to a third number, M, of physical elements,
wherein the configuration of the at least one processor to perform the elevation beamforming includes configuration to apply the tilt adjustment and the elevation precoding vector to each of the N subarrays separately.