Transmission and medium access control techniques for ultrasonic communications in the body

Patent metadata

Field	Value
Publication number	US-2016235301-A1
Application number	US-201415025622-A
Country	US
Kind code	A1
Filing date	Sep 30, 2014
Priority date	Sep 30, 2013
Publication date	Aug 18, 2016
Grant date	—

Abstract

Methods and devices for transmitting and receiving data through biological tissue using ultrasonic pulses are described. Methods of the present invention may set an initial time-hopping frame length and an initial spreading code length for data transmission. A request-to-transmit may be sent from a transmitter over a control channel at the initial frame and code length. The receiver may respond to the transmitter with a clear-to-transmit packet having feedback information. The feedback information can be used to improve a forward time-hopping frame length and a forward spreading code length. Embodiments of the invention may involve a body area network or body surface network comprising a plurality of implanted sensor nodes operating according to the disclosed invention.

First claim

1 . A method for transmitting data through biological tissue using ultrasonic pulses comprising:
setting, at a transmitter, an initial time-hopping frame length and an initial spreading code length for data transmission; sending, from the transmitter, a request-to-transmit packet to a receiver over a control channel at the initial time-hopping frame length and the initial spreading code length; receiving, at the transmitter, a clear-to-transmit packet from the receiver over the control channel, the clear-to-transmit packet comprising feedback information; calculating a private time-hopping sequence and private spreading code based on a pseudo-random sequence generator and an ID of the transmitter; establishing a connection with the receiver using the private time-hopping sequence and private spreading code; setting, at the transmitter, a forward time-hopping frame length and a forward spreading code length based on the feedback data in the clear-to-transmit packet; sending, from the transmitter, a data packet using the private time-hopping sequence, private spreading code, forward time-hopping frame length, and forward spreading code length; receiving, at the transmitter, an acknowledgement packet having updated feedback data; and setting, at the transmitter, the forward time-hopping frame length and the forward spreading code length based on the updated feedback information.

2 . The method of claim 1 , wherein the control channel is implemented through a time-hopping sequence and a spreading code known by all transmitters and receivers.

3 . The method of claim 1 , wherein the initial time-hopping frame length and the initial spreading code length are set based on a predetermined value.

4 . The method of claim 1 , wherein the initial and private spreading codes are based on M-ary PPM-BPSK.

5 . The method of claim 1 , wherein the initial and private spreading codes are based on M-ary PPM-OOK.

6 . The method of claim 1 , wherein the initial and private spreading codes are based on M-ary PPM-ASK.

7 . The method of claim 1 , wherein the initial and private spreading codes are based on M-ary PPM-FSK.

8 . The method of claim 1 , wherein the initial and private spreading codes are based on M-ary PPM-PPM.

9 . The method of claim 1 , wherein the feedback information is a measured interference value, and the method further comprises the step of calculating a forward time-hopping frame length and a forward spreading code length based on the measured interference value.

10 . The method of claim 1 , wherein the updated feedback information is a measured interference value, and the method further comprises the step of calculating the forward time-hopping frame length and the forward spreading code length based on the measured interference value.

11 . The method of claim 1 , further comprising:
measuring, at the transmitter, an interference value; wherein the data packet comprises transmitter feedback data based on the measured interference value.

12 - 25 . (canceled)

26 . A transmitter for sending data through biological tissue using ultrasonic pulses comprising:
a symbol mapper module; a code spreader module in electronic communication with the symbol mapper module; a time-hopper module in electronic communication with the code spreader module; a pulse shaping module in electronic communication with the time-hopper module; and a digital-to-analog converter in electronic communication with the pulse shaping module.

27 . The transmitter of claim 26 , wherein the symbol mapper module transforms information into M-ary symbols.

28 . The transmitter of claim 27 , wherein the code spreader module distributes the M-ary symbols into chips based on a pseudo-random spreading code.

29 . The transmitter of claim 28 , wherein the time-hopper module spreads the chips in time according to a selected time-hopping pattern.

30 . The transmitter of claim 29 , wherein the pulse shaping module maps the chips to position-modulated pulses, creating a train of position-modulated pulses following a predefined time-hopping pattern.

31 . The transmitter of claim 26 , wherein the pulse shaping module comprises a finite impulse response filter whose coefficients represent the samples of an nth-order derivative gaussian pulse or a chirp sequence.

32 . A data structure for communication through biological tissue using ultrasonic pulses comprising:
a packet synchronization preamble; a time-hopping synchronization preamble; a packet header comprising:
a start packet delimiter;
a packet size value;
a packet type value;
a transmitter ID;
a receiver ID;
a time-hopping frame length feedback value; and
a spreading code length feedback value;
a packet payload; and
a checksum value.

Assignees

• Galluccio Laura
• Palazzo Sergio
• Univ New York State Res Found

Inventors

• Melodia Tommaso
• Santagati Giuseppe Enrico
• Galluccio Laura
• Palazzo Sergio

Classifications

• A61B5/0024

  for multiple sensor units attached to the patient, e.g. using a body or personal area network · CPC title

• G08C23/02

  using infrasonic, sonic or ultrasonic waves · CPC title

• A61B5/0028 Primary

  Body tissue as transmission medium, i.e. transmission systems where the medium is the human body · CPC title

• H04B1/71635

  Transmitter aspects (H04B1/7174 takes precedence) · CPC title

• H04B2001/6908

  using time hopping · CPC title