Active load modulation transceiver

Patent metadata

Field	Value
Publication number	US-10992504-B2
Application number	US-201916246297-A
Country	US
Kind code	B2
Filing date	Jan 11, 2019
Priority date	Jan 11, 2018
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

In accordance with a first aspect of the present disclosure, an active load modulation (ALM) transceiver is provided, comprising a transmitter configured to send a transmit signal to an external device, wherein the transceiver is configured to adjust one or more parameters of the transmit signal at the end of at least one burst of said transmit signal. In accordance with a second aspect of the present disclosure, a method of operating an active load modulation (ALM) transceiver is conceived, comprising sending, by a transmitter of the transceiver, a transmit signal to an external device, and adjusting, by the transceiver, one or more parameters of the transmit signal at the end of at least one burst of said transmit signal.

First claim

The invention claimed is:

1. An active load modulation, ALM, transceiver, comprising a transmitter configured to send a transmit signal to an external device, wherein the transceiver is configured to adjust a plurality of parameters of the transmit signal at a final portion of at least one burst of said transmit signal, wherein adjusting the parameters comprises adjusting both a phase of the transmit signal and adjusting a pulse width of the transmit signal.

2. The transceiver of claim 1 , wherein the transceiver is configured to adjust said parameters utilizing preconfigured parameter settings.

3. The transceiver of claim 1 , further comprising a controller that is configured to monitor one or more system characteristics and to adjust the parameters in dependence on said system characteristics.

4. The transceiver of claim 3 , wherein the system characteristics comprise a settling of the transmit signal on an antenna of the transceiver.

5. The transceiver of claim 3 , wherein the system characteristics comprise a phase error of a local clock signal with respect to a signal received from the external device.

6. The transceiver of claim 1 , further comprising a receiver and at least one adjustable resistance coupled to a plurality of input or output terminals of the transmitter and to a plurality of input or output terminals of the receiver.

7. The transceiver of claim 6 , further comprising a controller configured to adjust said adjustable resistance.

8. The transceiver of claim 7 , wherein the adjustable resistance comprises at least one active device, and wherein the controller is configured to adjust the adjustable resistance by applying an analog control signal to said active device.

9. The transceiver of claim 7 , wherein the adjustable resistance comprises passive resistance elements, and wherein the controller is configured to adjust the adjustable resistance by digitally switching said passive resistance elements.

10. The transceiver of claim 6 , wherein the input or output terminals of the transmitter and the input or output terminals of the receiver are the same terminals.

11. The transceiver of claim 6 , wherein the input or output terminals of the transmitter and the input or output terminals of the receiver are separate terminals, and wherein a first adjustable resistance is coupled to the input or output terminals of the transmitter, and a second adjustable resistance is coupled to the input or output terminals of the receiver.

12. The transceiver of claim 1 , further comprising a coupling network between the transmitter and an antenna of the transceiver, wherein said coupling network comprises a plurality of capacitors for implementing an impedance optimization between the antenna and input or output terminals of the transmitter.

13. A radio frequency identification, RFID, transponder, comprising the transceiver of claim 1 .

14. A method of operating an active load modulation, ALM, transceiver, comprising sending, by a transmitter of the transceiver, a transmit signal to an external device, and adjusting, by the transceiver, a plurality of parameters of the transmit signal at a final portion of at least one burst of said transmit signal, wherein adjusting the parameters comprises adjusting a phase of the transmit signal and adjusting a pulse width of the transmit signal.

Assignees

• Nxp Bv

Inventors

• Zoescher Lukas
• Merlin Erich
• Muehlmann Ulrich Andreas

Classifications

• H04B5/45

  Transponders · CPC title

• H04B5/26

  using coils · CPC title

• H04B5/77 Primary

  for interrogation · CPC title

• H04L7/02

  Speed or phase control by the received code signals, the signals containing no special synchronisation information {(H04L7/0075 takes precedence)} · CPC title

• H04L27/20 Primary

  Modulator circuits; Transmitter circuits · CPC title