On-chip highly-efficient antennas using strong resonant coupling
The invention relates to an antenna structure for coupling electromagnetic energy between a chip and an off-chip element, including a first resonant structure disposed on or in a chip. The first resonant structure is configured to have a first resonant frequency. The antenna structure also includes a second resonant structure disposed on or in an off-chip element. The second resonant structure is configured to have a second resonant frequency substantially the same as the first resonant frequency. The first resonant structure and the second resonant structure are mutually disposed within a near field distance of each other to form a coupled antenna structure that is configured to couple electromagnetic energy between the chip and the off-chip element. The electromagnetic energy has a selected wavelength in a wavelength range from microwave to sub-millimeter wave. The invention also relates to a method of calculating dimensions for a highly coupled antenna structure.
1. An antenna structure for coupling electromagnetic energy between a chip and an off-chip element, comprising:
a first resonant structure disposed on or in said chip, said first resonant structure configured to have a first resonant frequency; and
a second resonant structure disposed on or in said off-chip element, said second resonant structure configured to have a second resonant frequency substantially the same as said first resonant frequency, said first resonant structure and said second resonant structure being mutually disposed within a near field distance of each other to form a coupled antenna structure configured to couple electromagnetic energy between said chip and said off-chip element, said electromagnetic energy having a selected wavelength in a wavelength range from microwave to sub-millimeter wave; at least a selected one of said first resonant structure and said second resonant structure comprises a resonant loop and a resonant capacitance.
2. The antenna structure of claim 1 , wherein said off-chip element is selected from the group consisting of a circuit board, a thin film structure, a redistribution layer (RDL), a micro electro mechanical system (MEMS) based structure, a nano electro mechanical system (NEMS) based structure, and a different chip.
3. The antenna structure of claim 1 , further comprising a low loss dielectric disposed between said chip and said off-chip element.
4. The antenna structure of claim 3 , wherein said low loss dielectric comprises air.
5. The antenna structure of claim 1 , further comprising a vacuum disposed between said chip and said off-chip element.
6. The antenna structure of claim 1 , wherein said chip comprises a flip chip attached to said off-chip element by a selected one of solder bumps and gold bumps.
7. The antenna structure of claim 6 , wherein an efficiency of coupling is substantially independent of a tilt of said chip relative to said off-chip element caused by different heights of said bumps.
8. The antenna structure of claim 6 , wherein an efficiency of coupling is substantially independent of a lateral translation attachment alignment of said flip chip.
9. The antenna structure of claim 1 , wherein said antenna has dimensions calculated according to a method comprising the steps of:
providing a desired resonant frequency for said highly coupled antenna structure;
providing a type of resonant antenna structure for each of two antennas of said highly coupled antenna structure;
providing an equation that calculates the quantity
Q
load
Q
total
for said highly coupled antenna structure;
selecting values of R L and physical dimensions of said highly coupled antenna structure; calculating said quantity
Q
load
Q
total
;
and
iteratively repeating said steps of selecting and calculating to maximize said quantity
Q
load
Q
total
.
10. The antenna structure calculated according to the method of claim 9 , wherein said step of providing an equation comprises providing the equation:
1
Q
total
=
1
Q
ohmic
+
1
Q
rad
+
1
Q
substrate_loss
+
1
Q
load
.
11. An antenna structure for coupling electromagnetic energy between a chip and an off-chip element, comprising:
a first resonant structure disposed on or in said chip, said first resonant structure configured to have a first resonant frequency; and
a second resonant structure disposed on or in said off-chip element, said second resonant structure configured to have a second resonant frequency substantially the same as said first resonant frequency, said first resonant structure and said second resonant structure being mutually disposed within a near field distance of each other to form a coupled antenna structure configured to couple electromagnetic energy between said chip and said off-chip element, said electromagnetic energy having a selected wavelength in a wavelength range from microwave to sub-millimeter wave;
wherein at least one of said first resonant structure and said second resonant structure comprises a selected one of a dipole antenna, a slot antenna, a yagi antenna, a patch antenna, a log-periodic antenna, and an antenna comprising a structure selected from the group consisting of a MEMS structure, a NEMS structure, a meta material and a periodic structure.
12. The antenna structure of claim 11 , wherein said off-chip element is selected from the group consisting of a circuit board, a thin film structure, a redistribution layer (RDL), a micro electro mechanical system (MEMS) based structure, a nano electro mechanical system (NEMS) based structure, and a different chip.
13. The antenna structure of claim 11 , further comprising a low loss dielectric disposed between said chip and said off-chip element.
14. The antenna structure of claim 13 , wherein said low loss dielectric comprises air.
15. The antenna structure of claim 11 , further comprising a vacuum disposed between said chip and said off-chip element.
16. The antenna structure of claim 11 , wherein said chip comprises a flip chip attached to said off-chip element by a selected one of solder bumps and gold bumps.
17. The antenna structure of claim 16 , wherein an efficiency of coupling is substantially independent of a tilt of said chip relative to said off-chip element caused by different heights of said bumps.
18. The antenna structure of claim 16 , wherein an efficiency of coupling is substantially independent of a lateral translation attachment alignment of said flip chip.
19. The antenna structure of claim 11 , wherein said antenna has dimensions calculated according to a method comprising the steps of:
providing a desired resonant frequency for said highly coupled antenna structure;
providing a type of resonant antenna structure for each of two antennas of said highly coupled antenna structure;
providing an equation that calculates the quantity
Q
load
Q
total
for said highly coupled antenna structure;
selecting values of R L and physical dimensions of said highly coupled antenna structure;
calculating said quantity
Q
load
Q
total
;
and
iteratively repeating said steps of selecting and calculating to maximize said quantity
Q
load
Q
total
.
20. The antenna structure calculated according to the method of claim 19 , wherein said step of providing an equation comprises providing the equation:
1
Q
total
=
1
Q
ohmic
+
1
Q
rad
+
1
Q
substrate
_
loss
+
1
Q
load
.