Low Power Operations In A Wireless Tunneling Transceiver

• US 20160198410A1
• Filed: 01/05/2015
• Published: 07/07/2016
• Est. Priority Date: 01/05/2015
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Silicon Image, Inc. (Lattice Semiconductor Corporation)
• Inventors: Doan, Chinh Huy, Fan, Wen, Forbes, Mark, John, Brian Henry, Parker, James Ray, Cherniavsky, Dmitry, Kumar, Nishit
• Granted Patent: US 10,015,744 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04W 52/0229 where the received signal is a wanted signal
• CPC Class Codes: H04W 76/12 Setup of transport tunnels
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless tunneling system tunnels communications between a first host device and a second host device through a wireless link, while maintaining compliance of the communications between the first and second host devices with a wired communication protocol and operates in a power efficient manner. Two host devices may communicate with each other through a wireless link using the wireless tunneling system, as if two host devices were connected through the wired cable. The wireless tunneling system operates in one of a high power state and one or more low power states. In the high power state, the wireless tunneling system exchanges data at a higher data rate for tunneling. In the low power state, the wireless tunneling system disables power hungry components for conserving power.

Claims

1. A full-duplex transceiver device for wirelessly tunneling communications between a first host device and a second host device while maintaining compliance of the communications between the first and second host devices with a wired communication protocol, the transceiver device comprising:

a transmitter including;

a high frequency transmitting circuit operational in a high power state to receive transmit data from the first host device and to encode the transmit data in a first transmit baseband signal at a first data rate, the transmit data targeted for the second host device and compliant with the wired communication protocol, the high frequency transmitting circuit disabled in one or more low power states,

a low frequency transmitting circuit operational in the one or more low power states to generate a second transmit baseband signal at a second data rate lower than the first data rate, the second transmit baseband signal comprising control information, and

an up-converter circuit configured to receive the first transmit baseband signal when in the high power state and to receive the second transmit baseband signal when in the one or more low power states and to modulate the first or second transmit baseband signal onto a carrier signal to generate a wireless transmit signal for transmitting;

a receiver including;

a down-converter circuit configured to receive a wireless receive signal and to demodulate the wireless receive signal to generate a receive baseband signal,

a high frequency receiving circuit operational in the high power state to receive the receive baseband signal, the high frequency receiving circuit to decode the receive baseband signal to obtain receive data for providing to the first host device, the receive data compliant with the wired communication protocol, the high frequency receiving circuit disabled when in the one or more low power states, and

a low frequency receiving circuit operational in the one or more low power states to receive the receive baseband signal and to generate a control signal based on control information in the receive baseband signal; and

a state machine to control switching of the transceiver device between the high power state and the one or more low power states based in part on the control signal.

2. The transceiver of claim 1,

wherein the low frequency receiving circuit determines an on period of an envelope of the receive baseband signal, and

wherein the state machine controls an operation state of the transceiver device based at least in part of the determined on period of the envelope of the receive baseband signal.

3. The transceiver of claim 1, wherein the low frequency transmitting circuit comprises:

an envelope generator circuit to generate an envelope signal in which an on-period of the envelope signal encodes one of a plurality of wake-up events;

a pseudo random binary sequence generator to generate a plurality of pulses having pseudo-randomly varying pulse widths; and

a logic circuit to generate the second transmit baseband signal by outputting a constant voltage to represent an off-period of the envelope signal and by outputting the plurality of pulses to represent the on-period of the envelope signal.

4. The transceiver of claim 1, wherein the state machine in a proximity detection state periodically enables the low frequency transmitting circuit and the low frequency receiving circuit to perform a proximity detection sequence to detect another transceiver device within a predetermined proximity.

5. The transceiver of claim 4, wherein the state machine enters the high power state responsive to detecting another device within the predetermined proximity.

6. The transceiver of claim 4,

wherein the transceiver is operational in the proximity detection state to periodically enable the low frequency receiving circuit for a predetermined time period to search for a receive proximity detection signal, and

wherein the transceiver is further configured to, responsive to detecting the receive proximity detection signal during the predetermined time period, generate, by the low frequency transmitting circuit, a transmit proximity detection signal, and transition, by the state machine, the transceiver to the high power state.

7. The transceiver of claim 4,

wherein the transceiver is operational in the proximity detection state to periodically enable the low frequency transmitting circuit for a predetermined time period to generate a transmit proximity detection signal, and to enable the low frequency receiving circuit for another predetermined time period to search for a receive proximity detection signal generated in response to the transmit proximity detection signal, and

wherein, responsive to detecting the receive proximity detection signal, the transceiver is further configured to transition, by the state machine, the transceiver to the high power state.

8. The transceiver of claim 1, further comprising:

a mechanical switch activated based on physical proximity to a second transceiver device, the mechanical switch when activated to perform a reset that causes the transceiver to initiate a proximity detection process to detect the second transceiver.

9. The transceiver of claim 1, wherein, the transceiver is further configured to:

detect, when operating in the high power state, a detachment of the transceiver from the first host device;

responsive to detecting the detachment, enter a sleep state;

after a predefined time period, transition to a proximity detection state to determine if the transceiver is within proximity of another device; and

responsive to detecting proximity of the transceiver to the first host device, transitioning to the high power state.

10. The transceiver of claim 9, wherein when operating in a detached host low power state, transitioning to a proximity detection state responsive to failing to receive a keep-alive signal at the low frequency receiving circuit within a predefined time period.

11. The transceiver of claim 1, wherein the wired communication protocol is a Universal Serial Bus protocol.

12. A method for wirelessly tunneling communications between a first host device and a second host device while maintaining compliance of the communications between the first and second host devices with a wired communication protocol using a full-duplex transceiver, the method comprising:

receiving, by a high frequency transmitting circuit when operating in a high power state, transmit data from the first host device;

encoding, by the high frequency transmitting circuit, the transmit data in a first transmit baseband signal at a first data rate, the transmit data targeted for the second host device and compliant with the wired communication protocol;

generating, by a low frequency transmitting circuit when operating in one or more low power states, a second transmit baseband signal at a second data rate lower than the first data rate, the second transmit baseband signal comprising control information;

receiving, by an up-converter circuit, the first transmit baseband signal when in the high power state, and the second transmit baseband signal when in the one or more low power states;

modulating, by the up-converter circuit, the first or second transmit baseband signal onto a carrier signal to generate a wireless transmit signal for transmitting;

receiving, by a down-converter circuit, a wireless receive signal;

demodulating, by the down-converter circuit, the wireless receive signal to generate a receive baseband signal;

decoding, by a high frequency receiving circuit operating in the high power state, the receive baseband signal to obtain receive data for providing to the first host device, the receive data compliant with the wired communication protocol;

generating, by a low frequency receiving circuit operating in the one or more low power states, a control signal based on control information in the receive baseband signal; and

controlling, by a state machine, switching between the high power state and the one or more low power states based in part on the control signal.

13. The method of claim 12, further comprising:

determining an on period of an envelope of the receive baseband signal; and

controlling an operation state of the transceiver based at least in part of the determined on period of the envelope of the receive baseband signal.

14. The method of claim 12, further comprising:

generating, by an envelope generator circuit, an envelope signal in which an on-period of the envelope signal encodes one of a plurality of wake-up events;

generating, by a pseudo-random binary sequence generator, a plurality of pulses having pseudo-randomly varying pulse widths; and

generating, by a logic circuit, the second transmit baseband signal by outputting a constant voltage to represent an off-period of the envelope signal and by outputting the plurality of pulses to represent the on-period of the envelope signal.

15. The method of claim 12, further comprising:

periodically enabling the low frequency transmitting circuit and the low frequency receiving circuit to detect another transceiver device within a predetermined proximity.

16. The method of claim 15, further comprising:

entering the high power state responsive to detecting another device within the predetermined proximity.

17. The method of claim 15, further comprising:

periodically searching, in a proximity detection state, for a receive proximity detection signal for a predetermined time period; and

responsive to detecting the receive proximity detection signal during the predetermined time period, generating a transmit proximity detection signal, and transitioning to the high power state.

18. The method of claim 15, further comprising:

periodically generating, in a proximity detection state, a transmit proximity detection signal for a predetermined time period;

searching, in the proximity detection state, for a receive proximity detection signal generated in response to the transmit proximity detection signal for another predetermined time period; and

responsive to detecting the receive proximity detection signal, transitioning to the high power state.

19. The method of claim 12, further comprising:

detecting, when operating in the high power state, a detachment of the transceiver from the first host device;

responsive to the detecting the detachment, entering a sleep state;

after a predefined time period, transitioning to a proximity detection state to determine if the transceiver is within proximity of another device; and

responsive to detecting proximity of the transceiver to the first host device, transitioning to the high power state.

20. The method of claim 19, further comprising:

when operating in a detached host low power state, transitioning to a proximity detection state responsive to failing to receive a keep-alive signal at the low frequency receiving circuit within a predefined time period.