Backscatter communication systems, interrogators, methods of communicating in a backscatter system, and backscatter communication methods
First Claim
1. A backscatter communication system comprising:
- an interrogator including a transmitter configured to output a forward link communication and a receiver configured to receive a return link communication having a carrier component and a side band component, the receiver comprising circuitry configured to reduce the amplitude of the carrier component of the return link communication while substantially maintaining the amplitude of the side band component and to output the return link communication signal including the carrier component having the reduced amplitude and the side band component having the maintained amplitude; and
a communication device configured to modulate a carrier signal to communicate the return link communication responsive to reception of the forward link communication.
5 Assignments
0 Petitions
Accused Products
Abstract
The present invention includes backscatter communication systems, interrogators, methods of communicating in a backscatter system, and backscatter communication methods. According to one aspect of the present invention, a backscatter communication system includes an interrogator including a transmitter configured to output a forward link communication and a receiver configured to receive a return link communication having a carrier signal, the receiver being configured to reduce the amplitude of the carrier signal of the return link communication; and a communication device configured to modulate the carrier signal to communicate the return link communication responsive to reception of the forward link communication.
243 Citations
59 Claims
-
1. A backscatter communication system comprising:
-
an interrogator including a transmitter configured to output a forward link communication and a receiver configured to receive a return link communication having a carrier component and a side band component, the receiver comprising circuitry configured to reduce the amplitude of the carrier component of the return link communication while substantially maintaining the amplitude of the side band component and to output the return link communication signal including the carrier component having the reduced amplitude and the side band component having the maintained amplitude; and
a communication device configured to modulate a carrier signal to communicate the return link communication responsive to reception of the forward link communication. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A backscatter system interrogator comprising:
a receiver configured to receive a return link communication comprising a modulated continuous wave signal comprising a radio frequency continuous wave signal having a first frequency and a modulation signal having a different frequency, the receiver comprising circuitry configured to reduce the amplitude of the return link communication at the frequency of the radio frequency continuous wave signal while substantially maintaining the amplitude of the return link communication signal at other frequencies and to output the return link communication having the reduced amplitude at the frequency of the radio frequency continuous wave signal. - View Dependent Claims (9, 10, 11, 12, 13)
-
14. A coherent backscatter system interrogator comprising:
-
a transmitter configured to communicate a wireless forward link communication, a wireless continuous wave signal and a local continuous wave signal; and
a receiver configured to receive the local continuous wave signal from the transmitter and wireless return link communications comprising modulated continuous wave signals having a carrier component and a side band component, the receiver comprising circuitry configured to reduce the amplitude of the carrier component of the return link communications using the local continuous wave signal received from the transmitter while substantially maintaining the amplitude of the side band component and to output the return link communications including the carrier component having the reduced amplitude and the side band component having the substantially maintained amplitude. - View Dependent Claims (15, 16, 17, 18)
-
-
19. A method of communicating in a backscatter system comprising:
-
transmitting a forward link communication;
transmitting a wireless continuous wave signal;
receiving the forward link communication;
modulating the wireless continuous wave signal responsive to the receiving the forward link communication, the modulating providing a modulated continuous wave signal having a carrier component and a side band component;
receiving the modulated continuous wave signal;
reducing the amplitude of the carrier component of the modulated continuous wave signal while substantially maintaining the amplitude of the side band component; and
outputting the modulated continuous wave signal having the carrier component after the reducing. - View Dependent Claims (20, 21, 22, 23, 24, 25, 26, 27)
matching the amplitude of the local continuous wave signal with the amplitude of the modulated continuous wave signal;
adjusting the phase of the local continuous wave signal following the matching; and
summing the local continuous wave signal and the modulated continuous wave signal following the adjusting.
-
-
27. The method according to claim 26 wherein the adjusting comprises searching for a phase which provides maximum reduction of the amplitude of the carrier component of the modulated continuous wave signal at a frequency of the wireless continuous wave signal.
-
28. A backscatter communications method comprising:
-
transmitting a forward link communication and a wireless continuous wave signal using an interrogator;
receiving the forward link communication using a remote communication device;
communicating a return link communication comprising a modulated continuous wave signal responsive to the receiving the forward link communication, the communicating including modulating the wireless continuous wave signal using the remote communication device;
receiving the modulated continuous wave signal using the interrogator;
reducing the amplitude of the modulated continuous wave signal at a frequency of a carrier component of the modulated continuous wave signal while substantially maintaining the amplitude of the modulated continuous wave signal at other frequencies using the interrogator; and
outputting the modulated continuous wave signal having the reduced amplitude at the frequency of the carrier component. - View Dependent Claims (29, 30, 31, 32, 33, 34, 35, 36)
-
-
37. A coherent backscatter communication method comprising:
-
transmitting a wireless forward link communication;
transmitting a continuous wave signal;
providing the continuous wave signal as a local signal;
receiving the wireless forward link communication;
communicating a wireless return link communication having a carrier component and a side band component, the communicating including modulating the continuous wave signal following the receiving;
receiving the wireless return link communication;
reducing the amplitude of the carrier component of the wireless return link communication using the local signal while substantially maintaining the amplitude of the side band component; and
outputting the wireless return link communication having the carrier component having the reduced amplitude and the side band component having the substantially maintained amplitude. - View Dependent Claims (38, 39, 40, 41, 42, 43)
-
-
44. A method of communicating within a coherent backscatter communication system, the method comprising:
-
outputting a forward link communication;
outputting a wireless continuous wave signal;
providing a local continuous wave signal;
communicating a modulated continuous wave signal responsive to the outputting the forward link communication;
receiving the modulated continuous wave signal; and
reducing the amplitude of the modulated continuous wave signal including;
matching the amplitude of the local continuous wave signal with the amplitude of the received modulated continuous wave signal;
adjusting the phase of the local continuous wave signal following the matching providing an adjusted continuous wave signal; and
summing the adjusted continuous wave signal with the modulated continuous wave signal. - View Dependent Claims (45, 46, 47, 48, 49, 50)
-
-
51. A method of reducing power within a modulated return link continuous wave signal of a coherent backscatter communication system including an interrogator and a remote communication device, the method comprising:
-
transmitting a radio frequency forward link communication;
transmitting a radio frequency continuous wave signal having a first frequency;
providing a local continuous wave signal having the first frequency;
receiving the radio frequency forward link communication;
modulating the radio frequency continuous wave signal following the receiving the radio frequency forward link communication, the modulating comprising reflecting the radio frequency continuous wave signal using a modulation signal having a second frequency and providing a modulated continuous wave signal having a carrier component and plural side band components;
receiving the modulated continuous wave signal; and
reducing the amplitude of the carrier component of the modulated continuous wave signal including;
matching the amplitude of the local continuous wave signal with the amplitude of the modulated continuous wave signal;
adjusting the phase of the local continuous wave signal following the matching; and
summing the local continuous wave signal and the modulated continuous wave signal following the adjusting.
-
-
52. A backscatter communication system comprising:
-
an interrogator including a transmitter configured to output a forward link communication and a receiver configured to receive a return link communication having a carrier signal, wherein the transmitter is configured to apply a local continuous wave signal to the receiver and the receiver is configured to receive the local continuous wave signal, to adjust the amplitude and phase of the local continuous wave signal to provide an adjusted continuous wave signal, and to sum the adjusted continuous wave signal with the return link communication to reduce the amplitude of the carrier signal of the return link communication; and
a communication device configured to modulate the carrier signal to communicate the return link communication responsive to reception of the forward link communication. - View Dependent Claims (53)
-
-
54. A backscatter system interrogator comprising:
-
a transmitter configured to output a forward link communication, a radio frequency continuous wave signal and a local continuous wave signal; and
a receiver configured to receive a return link communication comprising a modulated continuous wave signal comprising a radio frequency continuous wave signal having a first frequency and a modulation signal having a different frequency, the receiver being further configured receive the local continuous wave signal, to adjust the amplitude and phase of the local continuous wave signal to provide an adjusted continuous wave signal, and to sum the adjusted continuous wave signal with the modulated continuous wave signal to reduce the amplitude of the return link communication at the frequency of the radio frequency continuous wave signal. - View Dependent Claims (55)
-
-
56. A coherent backscatter system interrogator comprising:
-
a transmitter configured to communicate a wireless forward link communication, a wireless continuous wave signal and a local continuous wave signal; and
a receiver configured to receive the local continuous wave signal from the transmitter and wireless return link communications comprising modulated continuous wave signals, the receiver being configured to adjust the amplitude and phase of the local continuous wave signal to provide an adjusted continuous wave signal, and to sum the adjusted continuous wave signal with the modulated continuous wave signal to reduce the amplitude of the return link communications. - View Dependent Claims (57)
-
-
58. A method of communicating in a backscatter system comprising:
-
transmitting a forward link communication;
transmitting a wireless continuous wave signal;
providing a local continuous wave signal;
receiving the forward link communication;
modulating the wireless continuous wave signal responsive to the receiving the forward link communication, the modulating providing a modulated continuous wave signal;
receiving the modulated continuous wave signal; and
reducing the amplitude of the modulated continuous wave signal including;
matching the amplitude of the local continuous wave signal with the amplitude of the modulated continuous wave signal;
adjusting the phase of the local continuous wave signal following the matching; and
summing the local continuous wave signal and the modulated continuous wave signal following the adjusting. - View Dependent Claims (59)
-
Specification