1. A method for transmitting information signals having a plurality of symbol vectors associated therewith on a radio channel comprising:
precoding said symbol vectors by multiplying said symbol vectors with:
a first column subset of a unitary matrix which spreads symbols in said symbol vectors across all virtual transmit antennas,
a second diagonal matrix which changes a phase of said virtual transmit antennas, and
a third precoding matrix which distributes transmit energy across physical transmit antennas,
further processing said precoded symbol vectors to generate said information signals, and
transmitting said information signals.
2. The method according to claim 1, wherein said physical transmit antennas are antenna ports.
3. The method according to claim 1, wherein said symbol vectors are first multiplied by said first column subset of unitary matrix, next multiplied by said second diagonal matrix and then multiplied by said third precoding matrix.
4. The method according to claim 1, wherein when transmitting using r layers, said third precoding matrix has l columns, said second diagonal matrix has l rows and l columns, said first column subset of unitary matrix has l rows and r columns, and said symbol vectors have r elements.
5. The method according to claim 1, wherein when transmitting using r layers, said third precoding matrix has r columns, said second diagonal matrix has r rows and r columns, said first column subset of unitary matrix is a unitary matrix having r rows and r columns, and said symbol vectors have r elements.
6. The method according to claim 1, wherein said step of further processing further comprises:
mapping precoded symbols to resource blocks to be transmitted via at least one of said transmit antennas; and
distributing said resource blocks over the resource element grid of an orthogonal frequency division multiplexing (OFDM) type of transmission.
7. The method according to claim 1, wherein phase shifts induced by said second diagonal matrix are varied with respect to a parameter that is a function of a position of the resource element used for transmitting a particular symbol vector.
8. The method according to claim 7, wherein said parameter is a subcarrier index.
9. The method according to claim 7, wherein said parameter is a data resource element index.
10. The method according to claim 1, wherein said first column subset of unitary matrix and said second diagonal matrix together exhibit the same structure as cyclic delay diversity (CDD) for spatial multiplexing when represented in the frequency domain.
11. The method according to claim 1, wherein said third precoding matrix is performing channel dependent precoding.
12. A transmitter for transmitting information signals having a plurality of symbol vectors associated therewith on a radio channel comprising:
a plurality of physical transmit antennas;
a processor for precoding said symbol vectors by multiplying said symbol vectors with:
a first column subset of a unitary matrix which spreads symbols in said symbol vectors across all virtual transmit antennas,
a second diagonal matrix which changes a phase of said virtual transmit antennas, and
a third precoding matrix which distributes transmit energy across said physical transmit antennas, and for
further processing said precoded symbol vectors to generate said information signals; and
a transmit chain of elements for transmitting said information signals.
13. The transmitter according to claim 12, wherein said physical transmit antennas are antenna ports.
14. The transmitter according to claim 12, wherein said symbol vectors are first multiplied by said first column subset of unitary matrix, next multiplied by said second diagonal matrix and then multiplied by said third precoding matrix.
15. The transmitter according to claim 12, wherein when transmitting using r layers, said third precoding matrix has l columns, said second diagonal matrix has l rows and l columns, said first column subset of unitary matrix has l rows and r columns, and said symbol vectors have r elements.
16. The transmitter according to claim 12, wherein when transmitting using r layers, said third precoding matrix has r columns, said second diagonal matrix has r rows and r columns, said first column subset of unitary matrix is a unitary matrix having r rows and r columns, and said symbol vectors have r elements.
17. The transmitter according to claim 12, wherein said step of further processing further comprises:
mapping precoded symbols to resource blocks to be transmitted via at least one of said transmit antennas; and
distributing said resource blocks over the resource element grid of an orthogonal frequency division multiplexing (OFDM) type of transmission.
18. The transmitter according to claim 12, wherein phase shifts induced by said second diagonal matrix are varied with respect to a parameter that is a function of a position of the resource element used for transmitting a particular symbol vector.
19. The transmitter according to claim 18, wherein said parameter is a subcarrier index.
20. The transmitter according to claim 18, wherein said parameter is a data resource element index.
21. The transmitter according to claim 12, wherein said first column subset of unitary matrix and said second diagonal matrix together exhibit the same structure as cyclic delay diversity (CDD) for spatial multiplexing when represented in the frequency domain.
22. The transmitter according to claim 12, wherein said third precoding matrix is performing channel dependent precoding.
23. A method for equalizing received information signals having a plurality of symbol vectors associated therewith comprising:
forming a channel estimate associated with said received information signals by multiplying an initial channel estimate with a plurality of matrices, said plurality of matrices including:
a first column subset of a unitary matrix,
a second diagonal matrix, and
a third precoding matrix, and
equalizing said information signals using said formed channel estimate.
24. The method according to claim 23, wherein said first column subset of said unitary matrix was used in transmit processing of said received information signals to spread symbols in said symbol vectors across all virtual transmit antennas,
said second diagonal matrix was used in said transmit processing to change a phase of said virtual transmit antennas, and
said third precoding matrix was used in said transmit processing to distribute transmit energy across physical transmit antennas.
25. The method according to claim 24, wherein said physical transmit antennas are antenna ports.
26. The method according to claim 24, wherein when said transmit processing was performed using r layers, said third precoding matrix has l columns, said second diagonal matrix has l rows and l columns, said first column subset of said unitary matrix has l rows and r columns, and said symbol vectors have r elements.
27. The method according to claim 24, wherein when said transmit processing was performed using r layers, said third precoding matrix has r columns, said second diagonal matrix has r rows and r columns, said first column subset of unitary matrix is a unitary matrix having r rows and r columns, and said symbol vectors have r elements.
28. The method according to claim 23, wherein said first column subset of said unitary matrix and said second diagonal matrix together exhibit the same structure as cyclic delay diversity (CDD) for spatial multiplexing when represented in the frequency domain.
29. The method according to claim 23, wherein said third precoding matrix is performing channel dependent precoding.
30. A processor for forming a channel estimate associated with received information signals by multiplying an initial channel estimate with a plurality of matrices, said plurality of matrices including:
a first column subset of a unitary matrix,
a second diagonal matrix, and
a third precoding matrix, and
wherein said processor uses said formed channel estimate to equalize said received information signals.
31. The processor according to claim 30, wherein said first column subset of said unitary matrix was used in transmit processing of said received information signals to spread symbols in said symbol vectors across all virtual transmit antennas,
said second diagonal matrix was used in said transmit processing to change a phase of said virtual transmit antennas, and
said third precoding matrix was used in said transmit processing to distribute transmit energy across physical transmit antennas.
32. The processor according to claim 31, wherein said physical transmit antennas are antenna ports.
33. The processor according to claim 31, wherein when said transmit processing was performed using r layers, said third precoding matrix has l columns, said second diagonal matrix has l rows and l columns, said first column subset of said unitary matrix has l rows and r columns, and said symbol vectors have r elements.
34. The processor according to claim 31, wherein when said transmit processing was performed using r layers, said third precoding matrix has r columns, said second diagonal matrix has r rows and r columns, said first column subset of unitary matrix is a unitary matrix having r rows and r columns, and said symbol vectors have r elements.
35. The processor according to claim 30, wherein said first column subset of said unitary matrix and said second diagonal matrix together exhibit the same structure as cyclic delay diversity (CDD) for spatial multiplexing when represented in the frequency domain.
36. The processor according to claim 30, wherein said third precoding matrix is performing channel dependent precoding.
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 variable valve system of an internal combustion engine for varying an operation manner of an engine valve by controlling an angular position of a control shaft, comprising:
a stopper mechanism that determines an angular range in which the control shaft is permitted to rotate about its axis;
an actuating mechanism that actuates the control shaft to rotate about its axis; and
a position matching device separate from the stopper mechanism that is practically assembled only when the actuating mechanism is being assembled, the position matching device when assembled restricting operation of the actuating mechanism in such a manner as to match a maximally operated position of the actuating mechanism with a maximally operated angular position of the control shaft.
2. A variable valve system as claimed in claim 1, in which the actuating mechanism comprises:
an externally threaded shaft that is turned about its axis in accordance with the operation condition of the engine;
an internally threaded nut member operatively engaged with the threaded shaft so that turning of the threaded shaft induces an axial movement of the nut member along the threaded shaft, the nut member being contactable with the position matching device when the latter is assembled;
a lever member connected to the control shaft to rotate therewith;
a link member that pivotally connects the lever member and the nut member; and
a guide member that is detachably connected to a housing of the actuating mechanism, the guide member, when connected to the housing, holding both the lever member and the link member keeping a given clearance between the nut member and a stopper means in the housing, the guide member being removed from the housing once the connection between the lever member and the link member is properly achieved.
3. A variable valve system as claimed in claim 2, further comprising:
a first member connected to the lever member to rotate therewith; and
a second member connected to the housing and arranged to surround the first member,
wherein the first member and second member constitute a rotation angle sensor that detects the angular portion of the control shaft.
4. A variable valve system as claimed in claim 3, in which an end of the control shaft is formed with a flange portion that is formed with threaded openings, in which the lever member is formed with bolt openings through which connecting bolts pass before being engaged with the threaded openings of the flange portion thereby to secure the lever member to the flange portion and in which the guide member is formed with openings that have a size larger than heads of the connecting bolts.
5. A variable valve system as claimed in claim 2, in which the guide member is formed with a curved recess that is shaped to snugly receive therein a unit that includes the lever member and the link member.
6. A variable valve system as claimed in claim 2, in which the lever member is formed with bolt openings through which bolts pass before being engaged with threaded openings formed in a flange portion formed on an end of the control shaft, the lever member and the flange portion having at their mutually facing portions male-female constructions that are mated when the lever member and the flange portion are secured to each other, and in which the bolts openings of the lever member are elongate openings that extend around the axis of the control shaft.
7. A variable valve system as claimed in claim 1, in which the actuating mechanism comprises:
an externally threaded shaft that is turned about its axis in accordance with the operation condition of the engine;
an internally threaded nut member operatively engaged with the threaded shaft so that turning of the threaded shaft induces an axial movement of the nut member along the threaded shaft, the nut member being contactable with the position matching device when the latter is assembled;
a lever member connected to the control shaft to rotate therewith;
a link member that pivotally connects the lever member and the nut member; and
a housing that houses therein the threaded shaft, the threaded nut member, the lever member and the link member,
and in which the position matching device comprises a positioning opening formed in the housing at a position where the nut member arrives when the same is maximally moved along the threaded shaft, the positioning opening being adapted to hold a positioning bolt that is projected into the housing to stop an excessive movement of the nut member.
8. A variable valve system as claimed in claim 7, further comprising a close bolt that is connected to the positioning opening in place of the positioning bolt once assemblage of the actuating mechanism is substantially finished.
9. A variable valve system as claimed in claim 1, further comprising:
a drive shaft synchronously rotated about its axis by a crankshaft of the engine, the drive shaft having a drive cam connected thereto;
a swing cam rotatably supported by the drive shaft, the swing cam having a cam surface that is contactable with a valve lifter of the engine valve to induce an openclose movement of the engine valve; and
a rocker arm having one end operatively connected to the drive cam through a link arm and the other end operatively connected to the swing cam through a link rod,
wherein when, upon energization of the actuating mechanism, the control shaft is rotated about its axis to assume a new angular position, a swing fulcrum of the rocker arm is changed and thus a position where the cam surface of the swing cam contacts the valve lifter is changed thereby varying the lift degree of the engine valve.
10. A variable valve system as claimed in claim 7, in which the positioning opening is internally threaded and in which an externally threaded portion of the positioning bolt is engaged with the threaded positioning opening.
11. A variable valve system as claimed in claim 7, in which the positioning opening is internally threaded and in which an externally threaded portion of a close bolt is engaged with the threaded positioning opening once the assemblage of the actuating mechanism is substantially finished.
12. A variable valve system as claimed in claim 7, in which the positioning bolt is temporally connected to the positioning opening.
13. A variable valve system as claimed in claim 7, further comprising a biasing member that is provided between the nut member and the housing to bias the nut member in a given axial direction of the threaded shaft.
14. A variable valve system of an internal combustion engine for varying an operation manner of an engine valve by controlling an angular position of a control shaft, comprising:
a stopper mechanism that determines an angular range in which the control shaft is permitted to rotate about its axis; and
an actuating mechanism that actuates the control shaft to rotate about its axis,
the actuating mechanism comprising:
an externally threaded shaft that is turned about its axis in accordance with the operation condition of the engine;
an internally threaded nut member operatively engaged with the threaded shaft so that turning of the threaded shaft induces an axial movement of the nut member along the threaded shaft, the nut member being contactable with the position matching device when the latter is assembled;
a transmission mechanism provided between the control shaft and the nut member to convert the axial movement of the nut member to a rotary motion of the control shaft;
a housing that houses therein the threaded shaft, the threaded nut member and the transmission mechanism; and
a position matching device that is practically assembled only when the actuating mechanism is being assembled, the position matching device when assembled restricting operation of the actuating mechanism in such a manner as to match a maximally operated position of the actuating mechanism with a maximally operated angular position of the control shaft.
15. A variable valve system as claimed in claim 14, in which the transmission mechanism comprises a lever member connected to the control shaft to rotate therewith; and a link member that pivotally connects the lever member and the nut member, and further comprises a guide member that is detachably connected to the housing of the actuating mechanism, the guide member, when connected to the housing, holding both the lever member and the link member keeping a given clearance between the nut member and a stopper means provided in the housing, the guide member being removed from the housing once the connection between the lever member and the link member is properly achieved.
16. A variable valve system as claimed in claim 15, further comprising:
a drive shaft synchronously rotated about its axis by a crankshaft of the engine, the drive shaft having a drive cam connected thereto;
a swing cam rotatably supported by the drive shaft, the swing cam having a cam surface that is contactable with a valve lifter of the engine valve to induce an openclose movement of the engine valve; and
a rocker arm having one end operatively connected to the drive cam through a link arm and the other end operatively connected to the swing cam through a link rod,
wherein when, upon energization of the actuating mechanism, the control shaft is rotated about its axis to assume a new angular position, a swing fulcrum of the rocker arm is changed and thus a position where the cam surface of the swing cam contacts the valve lifter is changed thereby varying the lift degree of the engine valve.
17. A variable valve system as claimed in claim 14, in which the position matching device comprises:
a positioning opening formed in the housing at a position where the nut member arrives when the same is maximally moved along the threaded shaft; and
a positioning bolt that is engageable with the positioning opening to be projected into the housing to stop an excessive movement of the nut member.
18. A variable valve system as claimed in claim 17, further comprises a close bolt that is connected to the positioning opening in place of the positioning bolt once assemblage of the actuating mechanism is substantially finished.