Methods for Increasing RF Throughput Via Usage of Tunable Filters

Abstract

Methods and devices are described for increasing RF throughput in a multiple RF paths RF transmit/receive system with a plurality RF transmit/receive systems. In one case a tunable notch filter is used to reduce channel interference between the plurality of RF transmit/receive systems.

1 . A radio frequency (RF) circuital arrangement comprising:
 a first transmit/receive system comprising a first transmit path configured to transmit a first transmit RF signal at a first transmit/receive port, and a first receive path configured to receive a first receive RF signal at the first transmit/receive port;   a second transmit/receive system comprising a second transmit path configured to transmit a second transmit RF signal at a second transmit/receive port, and a second receive path configured to receive a second receive RF signal at the second transmit/receive port, and   one or more tunable notch filters configured to reduce a radio frequency interference of a transmit/receive system of the first and second transmit/receive systems over the other transmit/receive system.   
     
     
         2 . The RF circuital arrangement of  claim 1 , wherein a tunable notch filter of the one or more tunable notch filters is connected between a transmit/receive port of the first and the second transmit/receive ports and a duplexer unit in correspondence of the transmit/receive port. 
     
     
         3 . The RF circuital arrangement of  claim 1 , wherein a tunable notch filter of the one or more tunable notch filters is connected between a duplexer unit of a transmit/receive system of the first and the second transmit/receive systems and an input RF amplifier of the transmit/receive system. 
     
     
         4 . The RF circuital arrangement of  claim 1 , wherein the tunable notch filter of the one or more tunable notch filters is connected between a transmit amplifier of a transmit/receive system of the first and the second transmit/receive systems and a duplexer unit in correspondence of the transmit/receive system. 
     
     
         5 . The RF circuital arrangement of any one of  claims 2 - 4 , wherein the tunable notch filter is connected in a series and/or a shunt configuration. 
     
     
         6 . The RF circuital arrangement of  claim 1 , further comprising one or more RF switches, wherein the one or more RF switches are configured to enable and/or disable an effect of the one or more tunable notch filters over a transmit/receive system of the first and second transmit/receive systems. 
     
     
         7 . The RF circuital arrangement of  claim 6 , wherein a switch of the one or more RF switches is connected in parallel to a tunable notch filter of the one or more tunable notch filters. 
     
     
         8 . The RF circuital arrangement of  claim 7 , wherein the switch is connected between a first and a second input/output terminal of the tunable notch filter. 
     
     
         9 . The RF circuital arrangement of  claim 6 , wherein a switch of the one or more switches is connected in series to a tunable notch filter of the one or more tunable notch filters. 
     
     
         10 . The RF circuital arrangement of  claim 7  or  claim 9 , wherein a switch of the one or more switches comprises stacked transistors. 
     
     
         11 . The RF circuital arrangement of  claim 1 , wherein a tunable notch filter of the one or more tunable notch filters is a band-reject filter configured to reject a frequency band in correspondence of a first transmit/receive channel and to pass a frequency band in correspondence of a second transmit/receive channel adjacent to the first transmit/receive channel. 
     
     
         12 . The RF circuital arrangement of  claim 11 , wherein the frequency band is in correspondence of one of: a) a frequency of operation of a transmit RF signal of the first and the second transmit RF signals, b) a harmonic of a), and c) an intermodulation product of any combination of a) and b). 
     
     
         13 . The RF circuital arrangement of  claim 1 , wherein a tunable notch filter of the one or more tunable notch filters comprises one or more variable reactive elements. 
     
     
         14 . The RF circuital arrangement of  claim 13 , wherein the one or more variable reactive elements are partitioned in one or more stages interconnected via series and/or shunt connections. 
     
     
         15 . The RF circuital arrangement of  claim 13 , wherein a reactive element of the one or more variable reactive elements comprises one of: a) a digitally tunable capacitor, and b) a digitally tunable inductor. 
     
     
         16 . The RF circuital arrangement of  claim 1 , wherein during operation of the circuital arrangement, the first and the second transmit/receive systems are adapted to simultaneously transmit and/or receive an RF signal over a channel of a plurality of channels of a frequency band. 
     
     
         17 . The RF circuital arrangement of  claim 1 , wherein the first transmit/receive port comprises a first transmit/receive antenna and the second transmit/receive port comprises a second transmit/receive antenna. 
     
     
         18 . The RF circuital arrangement of  claim 1 , further comprising one or more transmit/receive systems similar to the first/second transmit/receive systems, wherein one or more of the one or more tunable notch filters are configured to reduce a radio frequency interference of a transmit/receive system of the RF circuital arrangement over the other transmit/receive systems of the RF circuital arrangement. 
     
     
         19 . A radio frequency (RF) integrated circuit comprising:
 an RF switch comprising a first switch terminal and a second switch terminal;   a RF tunable notch filter comprising a first port and a second port, wherein in a first configuration of the RF integrated circuit the first port is connected to the first switch terminal and the second port is connected to the second switch terminal, and in a second configuration of the RF integrated circuit the first port is connected to the second switch terminal;   a first input/output terminal connected to the first switch terminal;   a second input/output terminal connected to the second port; and   a control terminal,   wherein during operation, a control signal at the control terminal of the RF integrated circuit is configured to tune the RF tunable notch filter and/or control the RF switch to enable/disable a current flow through the RF tunable notch filter.   
     
     
         20 . The RF integrated circuit of  claim 19 , wherein the RF tunable notch filter comprises one or more variable reactive elements. 
     
     
         21 . The RF integrated circuit of  claim 20 , wherein a reactive element of the one or more variable reactive elements comprises one of: a) a digitally tunable capacitor, and b) a digitally tunable inductor. 
     
     
         22 . The RF integrated circuit of  claim 19  monolithically integrated on a same integrated circuit. 
     
     
         23 . The RF integrated circuit of  claim 22  fabricated using a technology comprising one of: a) Silicon on Sapphire, b) Silicon on Insulator, c) bulk-Silicon, and d) micro-electro-mechanical systems. 
     
     
         24 . The RF circuital arrangement of  claim 19  configured for operation in one of: a) a differential mode, and b) single-ended mode. 
     
     
         25 . A communication device for transmitting and receiving RF signals via one or more antennas, the communication device comprising the RF circuital arrangement of  claim 1  or  claim 18 , wherein the one or more antennas of the communication device are coupled to a plurality of transmit/receive ports of a plurality of transmit/receive systems of the RF circuital arrangement. 
     
     
         26 . The communication device of  claim 25  further comprising a transceiver unit, wherein during operation of the communication device, the transceiver unit is adapted to send/receive a plurality of transmit/receive RF signals to/from the plurality of transmit/receive systems of the RF circuital arrangement. 
     
     
         27 . The communication device of  claim 26 , wherein, during operation of the communication device, the transceiver unit is adapted to control the one or more tunable notch filters based on a characteristic of one or more RF signals of the plurality of transmit/receive RF signals. 
     
     
         28 . The communication device of  claim 27 , wherein the characteristic comprises a frequency spectra of the one or more RF signals. 
     
     
         29 . The communication device of  claim 28 , wherein the frequency spectra comprises at least one of: a) spectra of a frequency of operation of an RF signal of the one or more RF signals, b) spectra of a harmonic of a) and c) spectra of an intermodulation product of the one or more RF signals. 
     
     
         30 . A method for reducing radio frequency (RF) interference in an RF circuital arrangement, the method comprising:
 providing a plurality of RP transmit/receive systems coupled to a plurality RF antennas;   connecting in a path of a first RF transmit/receive system of the plurality of RF transmit/receive systems one or more RF tunable notch filters;   adjusting an RF tunable notch filter of the one or more RF tunable notch filters based on a characteristic of a transmit/receive RF signal of an RF transmit/receive system of the plurality of RF transmit/receive systems other than the first RF transmit/receive system; and   based on the adjusting, reducing an RF interference of the transmit/receive RF signal over the first RF transmit/receive system.   
     
     
         31 . The method of  claim 30 , further comprising:
 monitoring the characteristic of the transmit/receive RF signal;   based on the monitoring, detecting a change of the characteristic;   based on the detecting, further adjusting the RF tunable notch filter; and   based on the further adjusting, maintaining a reduced RF interference of the transmit/receive RF signal over the first RF transmit/receive system.   
     
     
         32 . The method of  claim 31 , further comprising:
 based on the maintaining, providing a larger operating frequency spectrum to the first transmit/receive RF system;   based on the providing, increasing a number of transmit/receive channels available to the first transmit/receive RF system; and   based on the increasing, increasing data throughput of the RF circuital arrangement.   
     
     
         33 . The method of  claim 30 , wherein the characteristic of the transmit/receive RF signal comprises a known operating frequency of the transmit/receive RF signal. 
     
     
         34 . The method of  claim 33 , wherein the known operating characteristic is in correspondence of a selected transmit/receive channel. 
     
     
         35 . The method of  claim 34 , wherein selection of the selected transmit/receive channel is performed by a transceiver unit. 
     
     
         36 . A radio frequency (RF) circuital arrangement comprising:
 a transmit path configured to transmit, during a transmit mode of operation of the RF circuital arrangement, a transmit RF signal at a transmit/receive port of the RF circuital arrangement;   a receive path configured to receive, during a receive mode of operation of the RF circuital arrangement, a receive RF signal at the transmit/receive port, and   a tunable notch filter configured to reduce a radio frequency interference of the transmit RF signal over the receive RF signal,   wherein during operation, the RF circuital arrangement is configured to simultaneously operate in the transmit and receive modes of operation.   
     
     
         37 . The RF circuital arrangement of  claim 36 , wherein the transmit path and the receive path are coupled to the transmit/receive port via a duplexer unit and wherein the tunable notch filter is connected between the duplexer unit and one of: a) an input RF amplifier of the receive path, b) a transmit RF amplifier of the transmit path, and c) the transmit/receive port. 
     
     
         38 . The RF circuital arrangement of  claim 36  or  claim 37 , wherein the tunable notch filter is connected in a series or shunt configuration. 
     
     
         39 . The RF circuital arrangement of  claim 38 , further comprising an RF switch coupled to the tunable notch filter, wherein during operation of the RF circuital arrangement, the RF switch is configured to enable and/or disable an effect of the tunable notch filter over the receive RF signal. 
     
     
         40 . The RF circuital arrangement of  claim 39 , wherein the switch comprises stacked transistors. 
     
     
         41 . The RF circuital arrangement of  claim 39 , wherein the switch is connected in one of: a) parallel configuration and b) serial configuration to the tunable notch filter. 
     
     
         42 . The RF circuital arrangement of  claim 36 , wherein the tunable notch filter is a band-reject filter configured, during operation of the RF circuital arrangement, to reject a frequency of operation of the transmit RF signal and to pass a frequency of operation of the receive RF signal. 
     
     
         43 . The RF circuital arrangement of  claim 42 , wherein:
 the frequency of operation of the transmit RF signal is in correspondence of a transmit channel of a plurality of transmit channels;   the frequency of operation of the receive RF signal is in correspondence of a receive channel of a plurality of receive channels; and   the RF circuital arrangement is configured to operate in one or more transmit and receive channels.   
     
     
         44 . The RF circuital arrangement of  claim 36 , wherein the tunable notch filter comprises one or more variable reactive elements. 
     
     
         45 . The RF circuital arrangement of  claim 44 , wherein a reactive element of the one or more variable reactive elements comprises one of: a) a digitally tunable capacitor, and b) a digitally tunable inductor. 
     
     
         46 . The RF circuital arrangement of  claim 36 , wherein the transmit/receive port comprises a transmit/receive antenna. 
     
     
         47 . A communication device for transmitting and receiving radio frequency (RF) signals via an antenna, the communication device comprising the RF circuital arrangement of  claim 43 , wherein the antenna of the communication device is coupled to the transmit/receive port of the RF circuital arrangement. 
     
     
         48 . The communication device of  claim 47  further comprising a transceiver unit, wherein during operation of the communication device, the transceiver unit is configured to send the transmit RF signal and to receive the receive RF signal respectively to/from the transmit path and receive path of the RF circuital arrangement. 
     
     
         49 . The communication device of  claim 48 , wherein, during operation of the communication device, the transceiver unit is adapted to control the tunable notch filter based on a transmit channel frequency and/or a receive channel frequency in correspondence of the transmit RF signal and the receive RF signal respectively. 
     
     
         50 . A method for reducing radio frequency (RF) interference in an RF circuital arrangement, the method comprising:
 providing an RF transmit path to transmit a transmit RF signal over an antenna;   providing an RF receive path to receive a receive RF signal over the antenna;   coupling a tunable notch filter to the RF transmit or the RF receive path;   adjusting the tunable notch filter based on a frequency of operation of the transmit RF signal; and   based on the adjusting, reducing an RF interference of the transmit RF signal over the receive RF signal.   
     
     
         51 . The method of  claim 50 , wherein the adjusting further comprises:
 further adjusting the tunable notch filter based on a frequency of operation of the receive RF signal.   
     
     
         52 . The method of  claim 50 , wherein the frequency of operation is in correspondence of a frequency of a selected transmit channel and wherein the adjusting is performed under control of a controller unit aware of the selected transmit channel. 
     
     
         53 . The method of  claim 52 , wherein the controller unit is a transceiver unit. 
     
     
         54 . The method of  claim 51 , wherein the adjusting is based on an intermodulation product of the frequency of operation of the transmit RF signal and the frequency of operation of the receive RF signal.