Ultra low power mesh network
A mesh receiver has a wakeup receiver for reception of a wakeup sequence formed by keyed RF or a sequence of wireless packets and gaps, a transmitter forming low speed RF wakeup sequence to other mesh stations, a mesh receiver for reception of high speed WLAN packets, the transmitter sending a wireless ACK packet in response to a wakeup sequence, the mesh receiver thereafter receiving wireless packets from a remote station, the mesh transmitter sending an ACK, the mesh station thereafter identifying a next hop station, and sending a wakeup sequence to that station, after receipt of an ACK, sending the data, the mesh receiver and mesh transmitter thereafter going to sleep.
1. A mesh device for receiving packets, the mesh device comprising a wakeup receiver, a mesh receiver, and a transmitter, the wakeup receiver receiving wakeup frames having a first and second wakeup sequence formed as a first and second bit sequence from the presence or absence of Radio Frequency (RF) energy;
the wakeup receiver operative to receive the first bit sequence followed by the second bit sequence, the first bit sequence having a receiver false alarm rate of 10% or more, the second bit sequence having a higher bit rate than the first bit sequence, the wakeup receiver operative to compare the first bit sequence to a first part of a wakeup pattern, and only when the first bit sequence matches the first part of the wakeup pattern, the wakeup receiver is operative to match the second bit sequence to the second part of the wakeup pattern, and upon a match of the second bit sequence to the second part of the wakeup pattern, enabling the mesh receiver for receiving packets according to at least one wireless protocol and also enabling the transmitter;
the transmitter sending a wireless acknowledgement (ACK) packet to a station sending the wakeup packet;
the mesh receiver receiving wireless packets and placing them into a queue, thereafter the transmitter sending an ACK packet and the mesh receiver going back into a sleep mode.
2. The mesh device of claim 1 where said wireless packets are at least one of an 802.11 packet, a Bluetooth packet, or a Zigbee packet.
3. The mesh device of claim 1 where the wakeup sequence has at least one of: a broadcast wakeup sequence or a unicast wakeup sequence.
4. The mesh device of claim 1 where the wakeup sequence includes a command identifying at least one of a protocol type or a channel for subsequent operation by the mesh receiver and the mesh transmitter.
5. The mesh device of claim 1 where the wakeup sequence changes according to a temporal pattern known to both a transmitter and a wakeup receiver.
6. The mesh device of claim 1 where, when packets are in a receive queue, the transmitter sends a wakeup sequence, and after receiving an acknowledgement of the wakeup sequence, the mesh device transmits any packets in the receive queue using a wireless protocol.
7. The mesh device of claim 1 where the mesh device transmits a mesh acknowledgement packet after receipt of a wakeup sequence.
8. The mesh device of claim 1 where the first bit sequence and the second bit sequence are of equal duration.
9. A wakeup transmitter for transmission of wakeup sequences, each wakeup sequence having a first part and a second part, the wakeup transmitter comprising:
buffer storage for the first part of the wakeup sequence and the second part of the wakeup sequence;
the first part of the wakeup sequence chosen to have a shortened number of bits resulting in a receive false alarm rate of 10% or more;
the buffer storage coupled to a Radio Frequency (RF) packet transmitter operative to periodically transmit the first part of the wakeup sequence followed by the second part of the wakeup sequence, the first part and second part each comprising a sequence of 1 and 0 bits, the second part having a faster bit rate than the first part;
the transmitter operative to transmit at least one of keyed RF or an entire data packet for the interval of a 1 bit, and an interval of non-transmission for a 0 bit, the 0 bit interval equal to the 1 bit interval for each respective first part and second part bit rate;
the sequential transmission and non-transmission intervals for the first part and the second part thereby forming a transmitted wakeup sequence.
10. The wakeup transmitter of claim 9 where the first part of the wakeup sequence has a duration substantially equal to the duration of the second part of the wakeup sequence.
11. The wakeup transmitter of claim 10 where the first part of the wakeup sequence is a universal sequence for a plurality of devices and the second part of the wakeup sequence is specific to a particular device.
12. The wakeup transmitter of claim 9 where the second part of the wakeup sequence has a broadcast pattern and a unicast pattern.
13. The wakeup transmitter of claim 9 where the data packet includes at least one of: an IEEE 802.11 packet, a Bluetooth packet, or a Zigbee packet.
14. A method for ultra-low power communications operative on a mesh device having a transmitter, a wakeup receiver for receiving low speed wakeup sequences comprising a first part at a first bit rate, the first part selected to have a receive false alarm rate of 10% or more, and a second part at a second bit rate greater than the first bit rate, and a mesh receiver for receiving high speed wireless data packets;
the wakeup transmitter periodically transmitting a sequence of 1s and 0s where each 1 is formed from an entire Radio Frequency (RF) packet, and each 0 is formed by non-transmission during an interval corresponding to the duration of an RF packet;
upon receipt of an acknowledgement (ACK) packet by the mesh receiver, the transmitter sending a data packet directed to the mesh station sending an ACK packet, the transmitter and mesh receiver thereafter going into a sleep mode upon receipt of an ACK packet from the remote mesh station receiving the data packet.
15. A method for ultra-low power communications operative on a mesh device having a wakeup receiver, a mesh receiver and a transmitter, the wakeup receiver operative continuously and operative to detect a received wakeup pattern formed from keyed Radio Frequency (RF) or wireless packets and gaps;
the wakeup pattern comprising a first bit pattern at a first bit rate and having a number of bits insufficient to reliably detect a packet, including a false packet detect rate of 10% or more, and a second bit pattern at a second bit rate greater than the first bit rate;
the wake-up receiver operative to compare a received wakeup pattern to a template pattern, the wakeup receiver thereafter causing the transmitter to send a wireless acknowledgement (ACK) packet compliant with at least one of: an IEEE 802.11 wireless packet, a Bluetooth wireless packet, or a Zigbee wireless packet;
the mesh receiver thereafter receiving data from a remote mesh station;
the transmitter thereafter sending a high speed wireless ACK packet, the mesh receiver and transmitter thereafter going into a sleep mode.
16. The method of claim 15 where the second bit rate is an integer multiple of the first bit rate.
17. The method of claim 15 where the first bit pattern includes a time-varying sequence known to a transmitter and to a receiver.
18. The method of claim 15 where the first bit pattern has a duration sufficient to provide a false alarm rate greater than 10%.