Stmicroelectronics S.r.l.

Stmicroelectronics Gmbh

France Brevets

Giuseppe Avellone

Agostino Galluzzo

Francesco Pappalardo

Francesco Rimi

Giuseppe Visalli

Ettore Messina

Alberto Serratore

Daniele Lo Iacono

Oleksandr Gorbachov

Piero Castoldi

Hisashi Kobayashi

Luca Fanucci

Salvatore Scaccianoce

Elena Salurso

Antonino Calcagno

Andrea Concil

Nicolò Ivan Piazzese

Daniele Grasso

Filippo Speziali

Lorena Simoni

Maristella Frazzetto

Riccardo Grasso

Alessandro Lattuca

A receiver is arranged to receive a plurality of Global Navigation Satellite System (GNSS) signals from up to four different satellite navigation systems including a GLONASS system, a BeiDou system, a GPS system, and a Galileo system. Received GNSS signals are mixed with a first local frequency signal to generate a plurality of mixed signals. The mixed signals are processed in up to three parallel branches. In a first branch, a first portion of the mixed signals are transformed by passing the first portion through a band-pass filter having a bandwidth between about 0 MHz and 46 MHz and by amplifying the filtered signals with an AGC circuit. In a second branch, a second portion of the mixed signals are transformed by rejecting image signals of the second portion with an image rejection filter and mixing image rejection filter output signals with a second local frequency signal to derive first remixed signals. In a third branch, a third portion of the mixed signals are transformed by adjusting a phase of the third portion to overlap a band of the first remixed signals. The adjusted third portion of the mixed signals and the first remixed signals are concurrently band pass filtered with a low IF filter.

Receiver for receiving a plurality of GNSS (Global Navigation Satellite System) signals

An electronic device includes an analog-to-digital converter adapted to receive a radio-frequency signal and adapted to provide therefrom a digital signal, wherein the radio-frequency signal may include an interference signal. The electronic device has a controller adapted to perform a digital measure on the digital signal and adapted to generate therefrom a selection signal having a first value indicating a non-interference condition in the radio-frequency signal and having a second value indicating an interference-condition in the radio-frequency signal. A selector is adapted to transmit the digital signal in case the selection signal has the first value and to transmit a signal replacing the digital signal in case the selection signal has the second value.

Electronic device for receiving a radio-frequency signal

A method and a system for the acquisition and tracking of BOC(m,n) modulated codes, m/n equal to an integer, in which a correlation function is calculated of the BOC(m,n) modulated code received from a remote transmitter with a code wlocally generated at a receiver terminal according to one from the following the relationships:(&#x3c4;)=(&#x3c4;)&#x2212;(&#x3c4;/2)&#x2212;(&#x3c4;/2)](&#x3c4;)=(&#x3c4;)&#x2212;(&#x3c4;/2)&#x2212;(&#x3c4;/2)](&#x3c4;)=(&#x3c4;)&#x2212;(&#x3c4;/4)+(&#x3c4;/4)](&#x3c4;)=(&#x3c4;)&#x2212;(&#x3c4;/4)+(&#x3c4;/4)](&#x3c4;)=[(&#x3c4;/4)+(&#x3c4;/4)](&#x3c4;)=[(&#x3c4;/2)&#x2212;(&#x3c4;/2)]

Method and system for resolving the acquisition ambiguity and the problem of false lock in tracking BOC(m,n) modulated signals, particularly for satellite positioning/navigation systems

The method is for estimating the fading coefficients of a plurality of transmission channels on which signals to be sent, generated as a function of a sequence of symbols, are transmitted according to a particular modulation, e.g. AM-PSK modulation. The fading coefficients are estimated by using estimations of the transmitted symbols obtained in advance, thus obtaining DC components of the received signal by coherent demodulation locked to the phases of the transmitted AM-PSK signals, and processing these DC components. The method may not require the choice of a stochastic distribution model of the channel fading, thus it remains efficient even when the channel characteristics vary significantly. Moreover, the method works correctly even if the received stream is disturbed by inter-symbolic interference (ISI) and/or by multi-path fading.

Method of estimating fading coefficients of channels and of receiving symbols and relative single or multi-antenna receiver and transmitter

Method of estimating fading coefficients of channels and of receiving symbols and related single or multi-antenna receiver and transmitter

Encoded digital symbols are transmitted via a first pair of antennas and at least one second pair of antennas. The sets of symbols used for the transmission via the second pair of antennas are re-ordered temporally into subsets of symbols with respect to the symbols used for the first pair of antennas. For the first pair of antennas, there is used a signal subjected to encoding with a code-division-multiple-access code and subjected to spreading with a spreading code, and, likewise, for the second pair or pairs of antennas there are used signals subjected to encoding with respective code-division-multiple-access code and subjected to spreading with a respective spreading code. At least one between the respective code-division-multiple-access code and the respective spreading code used for the transmission via the second pair of antennas is different from the code-division-multiple-access code and from the spreading code used for the transmission via the first pair of antennas. The solution can be extended to the use of a plurality of second pairs of antennas in transmission and/or to the use of a plurality of antennas in reception.

Method for transmitting signals using antenna diversity, for instance in mobile communication systems, transmitter, receiver and computer program product therefor

In order to perform, according to a received signal (r), a channel-estimation procedure and a cell-search procedure in cellular communication systems, there are executed at least one first operation of correlation of said received signal (r) with secondary synchronization codes (SSC) and a second operation of correlation of said received signal (r) with known midamble codes (mid, MPL, MPS), whilst said channel-estimation procedure comprises a third operation of correlation of at least part of said received signal (r) with known midamble codes (mid, MPL, MPS), said first, second, and third correlation operation being executed by sending at least part (e) of said received signal (r) to an input of a correlation bank. There are envisaged the operations of: sending, in a first time interval, the received signal (r) to said correlation bank for executing the first operation of correlation of said received signal (r) with secondary synchronization codes (SSC); sending, in a second time interval, at least part (e) of said received signal (r) to said same correlation bank for executing the second operation of correlation of said received signal (r) with known midamble codes (mid, MPL, MPS); sending, in a second time interval, the received signal (r) to said same correlation bank for executing the third operation of correlation of at least part (e) of said received signal (r) with known midamble codes (mid, MPL, MPS). Possible application is in mobile communication systems based upon standards such as UMTS, CDMA2000, IS95 or WBCDMA.

Method and apparatus for channel estimation and cell search in cellular communication systems, and corresponding computer program product

A receiver for receiving digital signals exposed to intersymbol interference as well as multiple access interference the method including linearly detecting said signals by combating said intersymbol interference by equalizing said received digital signals as well as mitigating said multiple access interference by detecting said digital signals using sliding window detection.

Low complexity detection in digital receivers

To generate the main scrambling code of order N and the secondary scrambling code of order K within the set identified by the primary scrambling code of order N, a first m-sequence and a second m-sequence are generated using Fibonacci linear feedback shift registers. The first m-sequence and the second m-sequence are modulo-2 added to form the I branch of the primary scrambling code. A first T-bit masking word and a second T-bit masking word of rankare generated that correspond to the polynomial time shifts, and the intermediate taps of the X and y registers respectively chosen by the masking words are modulo-2 added so as to generate a third sequence and a fourth sequence, which are modulo-2 added together to form the Q branch of the primary scrambling code. Starting from the least significant Kmax bits of the register X, of the K-th intermediate tap corresponding to the secondary scrambling code of order K within the set identified by the primary scrambling code of order N, a fifth sequence is generated, which, modulo-2 added to the second sequence, forms the I branch of the secondary scrambling code. By modulo-2 summing the intermediate taps of the register X masked by the first masking word of rank N, a sixth sequence is generated, which, modulo-2 added to the fourth sequence, forms the Q branch of the secondary scrambling code.

Process for generating codes for CDMA communications, system and computer program product therefor

A method for decoding signals with encoded symbols over a symbol interval that modulate a carrier. The method includes phase locking the signal to be decoded to obtain a phase-locked signal. The value assumed by the phase-locked signal on at least one subinterval in each symbol interval is detected. The method continues with attributing to the decoded symbol corresponding to each symbol interval a value that is a function of the value detected the subinterval. The subinterval in question can be a single subinterval located at the end of the symbol interval. Alternatively, the value assumed by the phase-locked signal on a plurality of subintervals in each symbol interval is detected, and a respective majority value of said phase-locked signal within said plurality of subintervals is identified. A value determined on the basis of the majority value is attributed to the decoded symbol corresponding to each symbol interval.

Method and system for coding/decoding signals and computer program product therefor

In a first step, slot synchronization may be obtained by setting in correlation the received signal with a primary sequence, which represents the primary channel, and storing the received signal. During a second step, the correlator may be re-used for correlating the received signal with a secondary sequence corresponding to the secondary synchronization codes. The correlator may include a first filter and a second filter connected in series, which receive a first secondary sequence and a second secondary sequence, which may include Golay sequences. Architectures of parallel and serial types, as well as architectures designed for reusing further circuit parts are also disclosed. The invention is particularly applicable in mobile communication systems based upon standards such as UMTS, CDMA2000, IS95, and WBCDMA.

Process and device for synchronization and codegroup identification in cellular communication systems and computer program therefor

To execute the cell-search procedure in a cellular communication system (such as a system based upon the 3GPP TDD standard), there are available identification codes for the second step (slot synchronization) and for the third step (identification of the scrambling codes). The identification codes are identified by a process of correlation with the received signal and are used for obtaining from a correspondence table the parameters for the execution of the second step (CD) or of the third step (SCR). The correspondence table is stored in a reduced form by the identification, according to rules of symmetry and redundancy, of subtables designed to generate the entire table by appropriate combination operations. The search procedure in the correspondence table thus reduced is conveniently modified by the introduction of the combination operations. A preferential application is in mobile communication systems based upon standards such as UMTS, CDMA2000, IS95 or WBCDMA.

Process and device for the cell search procedure in cellular communication systems, computer program product therefor

To obtain frame synchronization and identify the cell codegroup in a cellular communication system (such as a system based upon the standard 3GPP FDD), there are available the synchronization codes organized in chips or letters transmitted at the beginning of respective slots. Slot synchronization is obtained previously in a first step of the operation of cell search. During a second step, there are acquired, by means of correlation or fast Hadamard transform, the energy values corresponding to the respective individual letters with reference to the possible starting positions of the corresponding frame within the respective slot. Operating in a serial way at the end of acquisition of the aforesaid energy values of the individual letters, or else operating in parallel, the energies of the corresponding words are determined. Of these energies only the maximum word-energy value and the information for the corresponding starting position are stored in a memory structure. Said maximum value and said starting position identify, respectively, the cell codes and the frame synchronization sought. One application is in mobile communication systems based upon standards such as UMTS, CDMA2000, IS95, or WBCDMA.

Process and device for synchronization and codegroup identification in communication systems of the cellular type

Described herein is a method for parallel generating Walsh-Hadamard (WH) channelization codes and Orthogonal Variable Spreading Factor (OVSF) channelization codes, which are channelization codes formed by a plurality of strings of antipodal digits, each having a given length L and being identifiable by respective indices I formed by strings of binary digits, each having a given length N equal to the logarithm in base two of the length L of the channelization codes, the antipodal digits of the channelization codes assuming the values +1 and &#x2212;1 and the binary digits of said indices I assuming the values 0 and 1. The method according to the invention enables determination of the antipodal digits of the channelization codes according to the binary digits of the corresponding indices I, implementing specific EXOR logic operations, by means of which there are first generated intermediate binary digits, which are then encoded with the antipodal digits of the channelization codes using an encoding criterion according to which the intermediate binary digits 0 and 1 can be encoded, respectively, with the antipodal digits &#x2212;1 and +1 or else with the antipodal digits +1 and &#x2212;1 according to the type of binary encoding chosen a priori for the antipodal digits themselves.

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Palermo, Italy

Giuseppe Avellone