Method and apparatus for low power modulation and massive medium access control

• US 8,314,688 B2
• Filed: 08/22/2007
• Issued: 11/20/2012
• Est. Priority Date: 08/22/2007
• Status: Active Grant

• Current Assignee: TagArray, Inc. (Analog Devices, Inc.)
• Original Assignee: TagArray, Inc. (Analog Devices, Inc.)
• Inventors: Pahlavan, Kourosh, Eskafi, Farokh Hassanzadeh
• Primary Examiner(s): RENNER, BRANDON M
• Application Number:
  US11/843,543
• Publication Number:
  US 20090051496A1
• Time in Patent Office: 1,917 Days
• Field of Search: 370/213, 375/353
• US Class Current: 340/12.51
• CPC Class Codes: H04B 1/7176 Data mapping, e.g. modulation
• CPC Class Codes: H04B 2201/71632 Diversity
• CPC Class Codes: H04W 74/00 Wireless channel access
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An ultra low power, low complexity, low collision, deterministic modulation method that also works as a massive medium access mechanism for communication systems is based on positioning data in a communication resource space, such as time and frequency, such that the position of a symbol in that space determines its value and its access to the medium. The number base of the symbol is determined by the size of the subset of the resource space it is positioning itself in and, thereby, a few sparsely located symbols can convey a large value, while the remainder of the space can be simultaneously and massively used by other sparsely resource using members of the network.

Claims

1. A method, comprising:

transforming a digital word into linked words according to a linking algorithm, wherein each linked word represents a corresponding portion of the digital word, and wherein the linked words are M-bit words, M being an integer; and

from a transmitter, successively transmitting each of the linked words as a symbol in a time slot selected from a plurality of at least 2^M time slots according to a binary value of the successively transmitted linked word wherein a receiver is enabled to recover the digital word from the transmitted linked words according to the linking algorithm.

2. The method of claim 1, wherein said linking algorithm comprises an overlapping algorithm in which the linked words comprise overlapping portions of the digital word.

3. The method of claim 1, wherein the linking algorithm comprises a coding algorithm in which the digital word is segmented into portions corresponding to the linked words such that a first one of the linked words comprises a first one of the portions of the digital word and succeeding ones of the linked words each comprises its corresponding portion of the digital word and a code that is a function of the corresponding portion and all preceding portions.

4. The method of claim 1, wherein the linking algorithm comprises a linking-by-identifier algorithm in which the digital word is segmented into portions corresponding to the linked words such that each of the linked words equals its corresponding portion of the digital word and a session identifier (SID) that is a function of the digital word.

5. The method of claim 1, said method comprising an efficient medium access method for ultrawide band (UWB) communication, radio communication, Radio Frequency Identification (RFID) devices, or UWB-based RFID devices.

6. The method of claim 1, wherein said digital word comprises

a unique identifier.

7. The method for claim 3, wherein the code is a cyclic redundancy check (CRC) code.

8. The method of claim 1, wherein for each selected time slot, the transmitted symbol is an ultra wideband pulse.

9. An RFID ultra wideband (UWB) tag configured to transmit linked words according to the method of claim 8.