Pasi Tikka - Academia.edu (original) (raw)
Papers by Pasi Tikka
A mobile communication device with - a signal path, a signal path input and a signal path output,... more A mobile communication device with - a signal path, a signal path input and a signal path output, - one in the signal path between the signal path input and the signal path output impedance matching circuit interconnected with adjustable impedance for tuning an interconnected with the signal path output variable load impedance, - a control circuit for controlling the impedance matching circuit, - an interconnected in the signal path between the signal path input impedance matching circuit and power amplifier, - sequential transmission time slots in which the power amplifier is working and which are regularly interrupted by time slots in which the power amplifier is not working, in which - a transmit time slot begins at a time T0, - the power amplifier T0 + LVL works only from a time with his full power and LVL 0, - the control circuit adjusts the impedance of the impedance matching circuit within the time interval from T0 to T0 + IE, - the power amplifier only begins to work from a ...
With bulk acoustic wave resonator working, with a layer sequence, comprising: - a lower layer por... more With bulk acoustic wave resonator working, with a layer sequence, comprising: - a lower layer portion which includes a first electrode (E1), - an upper layer portion comprising a second electrode (E2), - a piezoelectric layer (PS) coupled between the first and second electrodes (E1, E2) is arranged, - in which between the first and second electrodes is possible the formation of a standing acoustic plate wave, which is characterized in the lateral direction by a lateral wave number k - in which the piezoelectric layer (PS) is made of a material showing anomalous dispersion behavior, wherein the acoustic plate wave generated by a real or complex lateral wave number Re {k > | Im {k} is characterized, in the piezoelectric layer (PS) having a frequency lower than the acoustic plate wave generated by a lateral wave number Re is characterized, and - in which the choice of material and the thickness ratio of the individual layers are set in the layer sequence such that the sequence of la...
To improve the filter response and the electrical adjustment of an operating with acoustic bulk w... more To improve the filter response and the electrical adjustment of an operating with acoustic bulk wave filter is proposed to provide a bilaterally symmetrical arrangement operable from bulk acoustic wave resonators, in the two signal paths are formed. Each signal path is at least connected in a complex impedance.
In one embodiment, a circuit arrangement comprising a transceiver unit (TU), one to the transceiv... more In one embodiment, a circuit arrangement comprising a transceiver unit (TU), one to the transceiver unit (TU) coupled to said switching means (SW) having a terminal (10) configured for coupling to an antenna device (AD), one to the switching means (SW) coupled control device (CD), wherein the control device (CD) is configured for operating the circuit arrangement in a first and in a second operating mode, wherein in the first operation mode, the switching means (SW) by the control device (CD) is configured such that a first signal from the transceiver unit (TU) via the switching device (SW) in a feedback loop back to the transceiver unit (TU) is directed, and in the second operating mode, the switching means (SW) by the control device (CD) is configured such that a second signal from the transceiver unit (TU) via the switching device (SW) (to the terminal 1 0) is directed or the second signal from the terminal (10) via the switching device (SW) (to the transceiver unit TU) is directed.
There is provided a wide-band impedance matching circuit operable with capacitive elements variab... more There is provided a wide-band impedance matching circuit operable with capacitive elements variable capacitance in the signal path, an inductive element in a parallel path which is connected in parallel to the signal path, as well as inductive elements in mass paths. The impedance matching allows communication in a first frequency band and receiving RF signals in a second frequency band.
The invention relates to a device (1) for wireless transmission of information, comprising a tran... more The invention relates to a device (1) for wireless transmission of information, comprising a transmitting / receiving unit (2), an antenna unit (3), an electrical signal path (SP) between the transmitting / receiving unit (2) and the antenna unit (3), a front end module is connected (FEM), which contains at least a duplexer (DPX) and which are electrically connected in the signal path (SP) between the transmitting / receiving unit (2) and the antenna unit (3), and a detection unit (DE) for detecting signals proportional to propagating in the signal path RF signals, wherein the detecting unit (DE) is electrically connected between the transmitting / receiving unit is coupled (2) and the front end module (FEM) to the signal path (SP). Further, a communication terminal for wireless information transmission with such a device (1) and a method for impedance matching between a transmitter / receiver unit (2) and an antenna unit (3) of a device (1) for wireless transmission of information ...
1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027), 1999
We discuss an acoustic loss mechanism in leaky surface-acoustic wave resonators on 36°YX-cut lith... more We discuss an acoustic loss mechanism in leaky surface-acoustic wave resonators on 36°YX-cut lithium tantalate substrate. Our recent acoustic field scans performed with an optical Michelson interferometer revealed a spatially asymmetric acoustic field atop the busbars of a resonator, giving rise to acoustic beams which escape the resonator area and lead to undesired losses. Here, we link the phenomenon with
1998 IEEE Ultrasonics Symposium. Proceedings (Cat. No. 98CH36102)
Measurements on the surface-acoustic wave profiles in various SAW devices have been performed wit... more Measurements on the surface-acoustic wave profiles in various SAW devices have been performed with a scanning laser interferometer. SAW profiles at frequencies up to 1 GHz are obtained with our interferometer. Fast automatic computer control enables high-resolution scans with a large number of measuring points at speeds up to 10 000 points/hour. Our interferometer can detect below one Angstrom vibrations of the surface. These capabilities have been utilized to scan modern SAW devices. The SAW beam in a SPUDT filter has been studied. In addition, a new acoustic loss mechanism has been detected in SAW resonators operating at 1 GHz via probing an IEF filter. Our measurements serve to unfold the direct connection between the acoustic losses present at selected frequencies and the corresponding increased insertion loss of the filter at these frequencies
Optics Letters, 2000
A scanning homodyne Michelson interferometer is constructed for two-dimensional imaging of highfr... more A scanning homodyne Michelson interferometer is constructed for two-dimensional imaging of highfrequency surface acoustic wave (SAW) f ields in SAW devices. The interferometer possesses a sensitivity of ϳ10 25 nm͞ p Hz, and it is capable of directly measuring SAW's with frequencies ranging from 0.5 MHz up to 1 GHz. The fast scheme used for locating the optimum operation point of the interferometer facilitates high measuring speeds, up to 50,000 points͞h. The measured f ield image has a lateral resolution of better than 1 mm. The fully optical noninvasive scanning system can be applied to SAW device development and research, providing information on acoustic wave distribution that cannot be obtained by merely electrical measurements.
Electronics Letters, 1999
Applied Physics Letters, 1999
Tämän kirjan tarkoitus on antaa valmius Unix-pohjaisen, tietoliikenneverkkoon liitetyn tietokonee... more Tämän kirjan tarkoitus on antaa valmius Unix-pohjaisen, tietoliikenneverkkoon liitetyn tietokoneen käyttämiselle. Kirjassa käsitellyt asiat antavat perustaidot, jotka hallitsemalla uusiin asioihin on mahdollista tutustua itsenäisesti. Annetut esimerkit kannattaa kokeilla tietokoneella jo kirjaa lukiessa. Kirjassa on Unixin käyttäminen kuvattu sellaisena kuin se on Teknillisen korkeakoulun IT-palvelukeskuksen tietokoneissa. Kaikki esimerkit eivät siis toimi täsmälleen samalla tavalla erilaisissa Unix-järjestelmissä, pieniä eroja saattaa esiintyä jopa IT-palvelukeskuksen eri koneiden välillä. Materiaali on jaettu kahteen osaan. Ensimmäinen osa käsittelee Unixia käyttöjärjestelmänä. Yleisten Unix-asioiden lisäksi käsitellään TKK:n IT-palvelukeskuksen Unix-järjestelmän erityispiirteitä. Toinen osa käsittelee viestintää Internetissä Unix-koneiden avulla. Mikäli tietokoneiden käyttäminen on ennestään tuttua, voidaan hypätä suoraan lukemaan näitä asioita. Muuten kannattaa tutustua ensimmäi...
2001 IEEE MTT-S International Microwave Sympsoium Digest (Cat. No.01CH37157)
ABSTRACT In order to gain a better understanding of the behavior of thin-film bulk-acoustic-wave ... more ABSTRACT In order to gain a better understanding of the behavior of thin-film bulk-acoustic-wave devices it is necessary to know the dispersion relation of an investigated layer stack. A laser interferometric measurement technique for mechanical surface vibrations is used, providing data to which numerical dispersion calculations are fitted. This method turned out to be a reliable source to determine the material parameters
One or more substrates on which filter with bulk acoustic wave resonators and the electrodes are ... more One or more substrates on which filter with bulk acoustic wave resonators and the electrodes are arranged flat, provided with a comprehensive a metal layer cover so appear disruptive parasitic capacitances, which may lead to a coupling of the two bulk acoustic wave resonators and a coupling of different filters, which the respective bulk acoustic wave resonators are assigned. To reduce the coupling is proposed to bind the metal layer via an electrical connection to a ground terminal of the filter arrangement and interconnect inductance in series in the connection. In this way, the coupling between the two bulk acoustic wave resonators is suppressed, and eliminates the undesirable mutual interference. If the invention is used in built up as a thin-film resonators duplexers, the isolation of the single filters of the duplexer is enhanced additionally.
With bulk acoustic wave resonator working with a layer sequence comprising: a lower layer portion... more With bulk acoustic wave resonator working with a layer sequence comprising: a lower layer portion which includes a first electrode (E1), an upper layer portion comprising a second electrode (E2), wherein the first and / or the second electrode consists of several layers, which are constructed from at least two different materials, a piezoelectric layer (PS1) interposed between the first and second electrodes (E1, E2) is arranged, wherein in parallel or in series to said resonator a capacitance is connected.
A designed for a first and second communication system, each different duplex operation of the ci... more A designed for a first and second communication system, each different duplex operation of the circuit arrangement can be operated for the transmission mode of a communication system with TDD duplex operation in a further operating condition in which the transmission signal of this first TDD communication system over the designed for an FDD duplex mode duplexer of the second communication system is passed.
Mit akustischen Volumenwellen arbeitender Resonator, mit einer Schichtenfolge, enthaltend: – eine... more Mit akustischen Volumenwellen arbeitender Resonator, mit einer Schichtenfolge, enthaltend: – einen unteren Schichtbereich, der eine erste Elektrode (E1) umfast, – einen oberen Schichtbereich, der eine zweite Elektrode (E2) umfast, – eine piezoelektrische Schicht (PS), die zwischen der ersten und zweiten Elektrode (E1, E2) angeordnet ist, – bei dem zwischen der ersten und zweiten Elektrode die Entstehung einer stehenden akustischen Plattenwelle moglich ist, welche in lateraler Richtung durch eine laterale Wellenzahl k x charakterisiert wird, die in zumindest einem Frequenzbereich einen reellen Anteil Re{k x } ≠ 0 aufweist, – bei dem die piezoelektrische Schicht (PS) aus einem Material besteht, das ein anomales Dispersionsverhalten zeigt, wobei die akustische Plattenwelle, die durch eine reelle oder komplexe laterale Wellenzahl Re{k x } ≠ 0, |Re{k x }| > |Im{k x }| charakterisiert ist, in der piezoelektrischen Schicht (PS) eine niedrigere Frequenz aufweist als die akustische Platte...
A mobile communication device with - a signal path, a signal path input and a signal path output,... more A mobile communication device with - a signal path, a signal path input and a signal path output, - one in the signal path between the signal path input and the signal path output impedance matching circuit interconnected with adjustable impedance for tuning an interconnected with the signal path output variable load impedance, - a control circuit for controlling the impedance matching circuit, - an interconnected in the signal path between the signal path input impedance matching circuit and power amplifier, - sequential transmission time slots in which the power amplifier is working and which are regularly interrupted by time slots in which the power amplifier is not working, in which - a transmit time slot begins at a time T0, - the power amplifier T0 + LVL works only from a time with his full power and LVL 0, - the control circuit adjusts the impedance of the impedance matching circuit within the time interval from T0 to T0 + IE, - the power amplifier only begins to work from a ...
With bulk acoustic wave resonator working, with a layer sequence, comprising: - a lower layer por... more With bulk acoustic wave resonator working, with a layer sequence, comprising: - a lower layer portion which includes a first electrode (E1), - an upper layer portion comprising a second electrode (E2), - a piezoelectric layer (PS) coupled between the first and second electrodes (E1, E2) is arranged, - in which between the first and second electrodes is possible the formation of a standing acoustic plate wave, which is characterized in the lateral direction by a lateral wave number k - in which the piezoelectric layer (PS) is made of a material showing anomalous dispersion behavior, wherein the acoustic plate wave generated by a real or complex lateral wave number Re {k > | Im {k} is characterized, in the piezoelectric layer (PS) having a frequency lower than the acoustic plate wave generated by a lateral wave number Re is characterized, and - in which the choice of material and the thickness ratio of the individual layers are set in the layer sequence such that the sequence of la...
To improve the filter response and the electrical adjustment of an operating with acoustic bulk w... more To improve the filter response and the electrical adjustment of an operating with acoustic bulk wave filter is proposed to provide a bilaterally symmetrical arrangement operable from bulk acoustic wave resonators, in the two signal paths are formed. Each signal path is at least connected in a complex impedance.
In one embodiment, a circuit arrangement comprising a transceiver unit (TU), one to the transceiv... more In one embodiment, a circuit arrangement comprising a transceiver unit (TU), one to the transceiver unit (TU) coupled to said switching means (SW) having a terminal (10) configured for coupling to an antenna device (AD), one to the switching means (SW) coupled control device (CD), wherein the control device (CD) is configured for operating the circuit arrangement in a first and in a second operating mode, wherein in the first operation mode, the switching means (SW) by the control device (CD) is configured such that a first signal from the transceiver unit (TU) via the switching device (SW) in a feedback loop back to the transceiver unit (TU) is directed, and in the second operating mode, the switching means (SW) by the control device (CD) is configured such that a second signal from the transceiver unit (TU) via the switching device (SW) (to the terminal 1 0) is directed or the second signal from the terminal (10) via the switching device (SW) (to the transceiver unit TU) is directed.
There is provided a wide-band impedance matching circuit operable with capacitive elements variab... more There is provided a wide-band impedance matching circuit operable with capacitive elements variable capacitance in the signal path, an inductive element in a parallel path which is connected in parallel to the signal path, as well as inductive elements in mass paths. The impedance matching allows communication in a first frequency band and receiving RF signals in a second frequency band.
The invention relates to a device (1) for wireless transmission of information, comprising a tran... more The invention relates to a device (1) for wireless transmission of information, comprising a transmitting / receiving unit (2), an antenna unit (3), an electrical signal path (SP) between the transmitting / receiving unit (2) and the antenna unit (3), a front end module is connected (FEM), which contains at least a duplexer (DPX) and which are electrically connected in the signal path (SP) between the transmitting / receiving unit (2) and the antenna unit (3), and a detection unit (DE) for detecting signals proportional to propagating in the signal path RF signals, wherein the detecting unit (DE) is electrically connected between the transmitting / receiving unit is coupled (2) and the front end module (FEM) to the signal path (SP). Further, a communication terminal for wireless information transmission with such a device (1) and a method for impedance matching between a transmitter / receiver unit (2) and an antenna unit (3) of a device (1) for wireless transmission of information ...
1999 IEEE Ultrasonics Symposium. Proceedings. International Symposium (Cat. No.99CH37027), 1999
We discuss an acoustic loss mechanism in leaky surface-acoustic wave resonators on 36°YX-cut lith... more We discuss an acoustic loss mechanism in leaky surface-acoustic wave resonators on 36°YX-cut lithium tantalate substrate. Our recent acoustic field scans performed with an optical Michelson interferometer revealed a spatially asymmetric acoustic field atop the busbars of a resonator, giving rise to acoustic beams which escape the resonator area and lead to undesired losses. Here, we link the phenomenon with
1998 IEEE Ultrasonics Symposium. Proceedings (Cat. No. 98CH36102)
Measurements on the surface-acoustic wave profiles in various SAW devices have been performed wit... more Measurements on the surface-acoustic wave profiles in various SAW devices have been performed with a scanning laser interferometer. SAW profiles at frequencies up to 1 GHz are obtained with our interferometer. Fast automatic computer control enables high-resolution scans with a large number of measuring points at speeds up to 10 000 points/hour. Our interferometer can detect below one Angstrom vibrations of the surface. These capabilities have been utilized to scan modern SAW devices. The SAW beam in a SPUDT filter has been studied. In addition, a new acoustic loss mechanism has been detected in SAW resonators operating at 1 GHz via probing an IEF filter. Our measurements serve to unfold the direct connection between the acoustic losses present at selected frequencies and the corresponding increased insertion loss of the filter at these frequencies
Optics Letters, 2000
A scanning homodyne Michelson interferometer is constructed for two-dimensional imaging of highfr... more A scanning homodyne Michelson interferometer is constructed for two-dimensional imaging of highfrequency surface acoustic wave (SAW) f ields in SAW devices. The interferometer possesses a sensitivity of ϳ10 25 nm͞ p Hz, and it is capable of directly measuring SAW's with frequencies ranging from 0.5 MHz up to 1 GHz. The fast scheme used for locating the optimum operation point of the interferometer facilitates high measuring speeds, up to 50,000 points͞h. The measured f ield image has a lateral resolution of better than 1 mm. The fully optical noninvasive scanning system can be applied to SAW device development and research, providing information on acoustic wave distribution that cannot be obtained by merely electrical measurements.
Electronics Letters, 1999
Applied Physics Letters, 1999
Tämän kirjan tarkoitus on antaa valmius Unix-pohjaisen, tietoliikenneverkkoon liitetyn tietokonee... more Tämän kirjan tarkoitus on antaa valmius Unix-pohjaisen, tietoliikenneverkkoon liitetyn tietokoneen käyttämiselle. Kirjassa käsitellyt asiat antavat perustaidot, jotka hallitsemalla uusiin asioihin on mahdollista tutustua itsenäisesti. Annetut esimerkit kannattaa kokeilla tietokoneella jo kirjaa lukiessa. Kirjassa on Unixin käyttäminen kuvattu sellaisena kuin se on Teknillisen korkeakoulun IT-palvelukeskuksen tietokoneissa. Kaikki esimerkit eivät siis toimi täsmälleen samalla tavalla erilaisissa Unix-järjestelmissä, pieniä eroja saattaa esiintyä jopa IT-palvelukeskuksen eri koneiden välillä. Materiaali on jaettu kahteen osaan. Ensimmäinen osa käsittelee Unixia käyttöjärjestelmänä. Yleisten Unix-asioiden lisäksi käsitellään TKK:n IT-palvelukeskuksen Unix-järjestelmän erityispiirteitä. Toinen osa käsittelee viestintää Internetissä Unix-koneiden avulla. Mikäli tietokoneiden käyttäminen on ennestään tuttua, voidaan hypätä suoraan lukemaan näitä asioita. Muuten kannattaa tutustua ensimmäi...
2001 IEEE MTT-S International Microwave Sympsoium Digest (Cat. No.01CH37157)
ABSTRACT In order to gain a better understanding of the behavior of thin-film bulk-acoustic-wave ... more ABSTRACT In order to gain a better understanding of the behavior of thin-film bulk-acoustic-wave devices it is necessary to know the dispersion relation of an investigated layer stack. A laser interferometric measurement technique for mechanical surface vibrations is used, providing data to which numerical dispersion calculations are fitted. This method turned out to be a reliable source to determine the material parameters
One or more substrates on which filter with bulk acoustic wave resonators and the electrodes are ... more One or more substrates on which filter with bulk acoustic wave resonators and the electrodes are arranged flat, provided with a comprehensive a metal layer cover so appear disruptive parasitic capacitances, which may lead to a coupling of the two bulk acoustic wave resonators and a coupling of different filters, which the respective bulk acoustic wave resonators are assigned. To reduce the coupling is proposed to bind the metal layer via an electrical connection to a ground terminal of the filter arrangement and interconnect inductance in series in the connection. In this way, the coupling between the two bulk acoustic wave resonators is suppressed, and eliminates the undesirable mutual interference. If the invention is used in built up as a thin-film resonators duplexers, the isolation of the single filters of the duplexer is enhanced additionally.
With bulk acoustic wave resonator working with a layer sequence comprising: a lower layer portion... more With bulk acoustic wave resonator working with a layer sequence comprising: a lower layer portion which includes a first electrode (E1), an upper layer portion comprising a second electrode (E2), wherein the first and / or the second electrode consists of several layers, which are constructed from at least two different materials, a piezoelectric layer (PS1) interposed between the first and second electrodes (E1, E2) is arranged, wherein in parallel or in series to said resonator a capacitance is connected.
A designed for a first and second communication system, each different duplex operation of the ci... more A designed for a first and second communication system, each different duplex operation of the circuit arrangement can be operated for the transmission mode of a communication system with TDD duplex operation in a further operating condition in which the transmission signal of this first TDD communication system over the designed for an FDD duplex mode duplexer of the second communication system is passed.
Mit akustischen Volumenwellen arbeitender Resonator, mit einer Schichtenfolge, enthaltend: – eine... more Mit akustischen Volumenwellen arbeitender Resonator, mit einer Schichtenfolge, enthaltend: – einen unteren Schichtbereich, der eine erste Elektrode (E1) umfast, – einen oberen Schichtbereich, der eine zweite Elektrode (E2) umfast, – eine piezoelektrische Schicht (PS), die zwischen der ersten und zweiten Elektrode (E1, E2) angeordnet ist, – bei dem zwischen der ersten und zweiten Elektrode die Entstehung einer stehenden akustischen Plattenwelle moglich ist, welche in lateraler Richtung durch eine laterale Wellenzahl k x charakterisiert wird, die in zumindest einem Frequenzbereich einen reellen Anteil Re{k x } ≠ 0 aufweist, – bei dem die piezoelektrische Schicht (PS) aus einem Material besteht, das ein anomales Dispersionsverhalten zeigt, wobei die akustische Plattenwelle, die durch eine reelle oder komplexe laterale Wellenzahl Re{k x } ≠ 0, |Re{k x }| > |Im{k x }| charakterisiert ist, in der piezoelektrischen Schicht (PS) eine niedrigere Frequenz aufweist als die akustische Platte...