Misalignment-tolerant high-density multi-transmitter/receiver modules for extremely-high frequency (EHF) close-proximity wireless connections
Docked devices communicate wirelessly and in close proximity using multiple transmitters of Extremely High-Frequency (EHF) signals of 30-300 GHz. The devices may not be precisely aligned when docked. Tolerance of misalignment is improved by adding barriers such as solid metal blocks or rows of metal-filled vias that have a spacing of less than one-quarter the EHF wavelength. The barriers reflect EHF radiation and prevent EHF radiation from penetrating the barrier. Barriers placed between adjacent transmitters and receivers block stray electromagnetic radiation from causing cross-talk. The barriers can be placed closer to the transmitters than to the receivers to allow for a wider area for reception, permitting a wider misalignment. EHF reflecting features such as ground planes spaced a quarter-wavelength apart may be added to an end of a substrate near a connecting edge to act as a barrier and reflect electromagnetic radiation back toward an intended receiver.
1. A close-proximity device comprising:
a substrate having metal wiring traces for making electrical connections;
a first integrated circuit (IC) chip mounted to the substrate, the first IC chip comprising:
a transmitter for generating a transmit signal having a transmit frequency;
a transmit transducer coupled to the transmitter, receiving the transmit signal from the transmitter and generating transmitted electromagnetic radiation in a transmit envelope of radiation;
a second IC chip mounted to the substrate, the second IC chip comprising:
a receiver for receiving a signal having a receive frequency;
a receive transducer, coupled to the receiver, receiving a portion of an envelope of received electromagnetic radiation emitted from a transmitter on a second device that is within a close proximity, the receive transducer generating a received signal; and
a barrier situated between the transmit transducer of the first IC chip and the receive transducer of the second IC chip, the barrier blocking a portion of the transmitted electromagnetic radiation from the transmit transducer to the receive transducer.
2. The close-proximity device of claim 1 , wherein the transmit frequency is an Extremely High-Frequency (EHF) within a range of 30-300 GHz.
3. The close-proximity device of claim 2 wherein the barrier is formed in the substrate;
wherein the barrier reflects a portion of the transmitted electromagnetic radiation away from the receive transducer;
wherein the barrier decreases a strength of the transmitted electromagnetic radiation that is collected by the receive transducer; and
wherein the barrier reflects a portion of the received electromagnetic radiation in a direction toward the receive transducer.
4. The close-proximity device of claim 3 wherein the barrier is an absorptive material formed in the substrate or on the substrate.
5. The close-proximity device of claim 3 wherein the barrier is a dielectric material formed in the substrate or on the substrate.
6. The close-proximity device of claim 3 wherein the barrier is a solid block of metal formed in the substrate or on the substrate.
7. The close-proximity device of claim 3 wherein the barrier is a plurality of metal planes formed within the substrate, wherein adjacent metal planes in the plurality of metal planes are parallel and spaced no more than one-quarter of a wavelength of the transmitted electromagnetic radiation.
8. The close-proximity device of claim 3 wherein the barrier is formed near a connecting end of the substrate, the connecting end of the substrate being closer to the second device than other portions of the substrate during proper alignment of devices.
9. The close-proximity device of claim 3 wherein the barrier is a row of vias formed in the substrate, the row of vias being located between the transmitter and the receiver.
10. The close-proximity device of claim 9 wherein the row of vias comprises metal-filled vias.
11. The close-proximity device of claim 10 wherein a spacing between adjacent vias in the row of vias is no more than one-quarter of a wavelength of the transmitted electromagnetic radiation.
12. The close-proximity device of claim 1 wherein the barrier is located between the transmitter and the receiver and closer to the transmitter than to the receiver;
whereby the barrier is not centered between the transmitter and the receiver, the row of vias being closer to the transmitter than to the receiver.
13. The close-proximity device of claim 1 wherein the close-proximity device comprises at least two transmitters and at least two receivers;
wherein each transmitter generates electromagnetic radiation in a transmit envelope that is directed toward a different receiver on the second device.
14. The close-proximity device of claim 1 wherein each transmitter generates electromagnetic radiation in a transmit envelope that is directed laterally in a direction that is substantially parallel to the substrate;
whereby transmitters emit electromagnetic radiation in a lateral direction.
15. The close-proximity device of claim 1 wherein each transmitter generates electromagnetic radiation in a transmit envelope that is directed upward in a direction that is substantially perpendicular to the substrate;
whereby transmitters emit electromagnetic radiation in an upward direction.
16. A close-proximity device comprising:
a substrate having metal wiring traces for making electrical connections;
a transmitter mounted to the substrate, for generating a transmit signal having a transmit frequency;
a transmit transducer coupled to the transmitter, receiving the transmit signal from the transmitter and generating transmitted electromagnetic radiation in a transmit envelope of radiation;
a receiver mounted to the substrate, for receiving a signal having a receive frequency;
a receive transducer, coupled to the receiver, receiving a portion of an envelope of received electromagnetic radiation emitted from a transmitter on a second device that is within a close proximity, the receive transducer generating a received signal; and
a barrier situated between the transmit transducer and the receive transducer, the barrier blocking a portion of the transmitted electromagnetic radiation from the transmit transducer to the receive transducer; and
a curved depression formed in a housing that encloses the close-proximity device, the curved depression having a shape that complements a connecting end of a second device;
wherein the barrier is formed below the curved depression of the second device;
wherein the curved depression guides the second device into close proximity and alignment due to matching shapes.
17. The close-proximity device of claim 16 wherein the transmitter in the second device emits electromagnetic radiation directed laterally in a direction that is substantially parallel to the substrate in the second device;
wherein the transmitter in the close-proximity device emits electromagnetic radiation directed upward in a direction that is substantially perpendicular to a substrate of the close-proximity device.
18. The close-proximity device of claim 16 , wherein the transmit frequency is an Extremely High-Frequency (EHF) within a range of 30-300 GHz.
19. The close-proximity device of claim 18 wherein the barrier is formed in the substrate;
wherein the barrier reflects a portion of the transmitted electromagnetic radiation away from the receive transducer;
wherein the barrier decreases a strength of the transmitted electromagnetic radiation that is collected by the receive transducer; and
wherein the barrier reflects a portion of the received electromagnetic radiation in a direction toward the receive transducer.
20. The close-proximity device of claim 19 wherein the barrier is an absorptive material formed in the substrate or on the substrate.