Abstract: A GPS receiver (10) is disclosed comprising a GPS antenna and a GPS RF front-end including an analogue to digital converter for sampling received GPS signals and a processor for outputting a stream of the GPS signal samples and inserting repeated instances of timing data indicating the timing of the sampling of the GPS signals in the stream in place of some of the GPS signal samples. Also disclosed is a corresponding method of providing a position fix and a computer program, computer-readable storage medium and apparatus for the same.

Abstract: A method of appending a position stamp to an image file of a photo or video clip taken with a digital camera having a GPS antenna and a GPS RF front-end including an analogue to digital converter for receiving GPS signals and outputting GPS signal samples together with a digital camera and computer for the same.

Abstract: A method for location-based zone triggering is disclosed. The method generally includes the step of (A) generating a position signal conveying a location of a device in at least two spatial dimensions in response to a plurality of navigation signals received from external the device and (B) generating a trigger signal at an interface based on the position signal, (i) a first aspect of the trigger signal indicating that the location is crossing a boundary of a zone, (ii) a second aspect of the trigger signal indicating that the device is one of entering the zone and leaving the zone and (iii) the interface adapting a zone module to communicate the trigger signal to an application module.

Abstract: A set of device parameters consisting of clock bias and position of a mobile device is determined without previous knowledge of the week number (WN) in that solutions of a set of equations derived from a least squares type weight function involving pseudoranges related to the device parameters via basic equations are attempted with a time of week (TOW) extracted from satellite signals and various week number candidates. A solution algorithm which iteratively solves the set of equations is used, each iteration step involving a linearization of the latter and resulting in corrections of the device parameters. After elimination of week numbers where the solution algorithm does not yield a solution a valid week number is selected from the remaining week numbers in that a deviation value is determined which reflects differential terms, i.e., differences between pseudorange values as measured and as derived from the set of device parameters according to the solution, e.g., by evaluation of the weight function.

Abstract: Complex digital data values derived from a DSSS signal, in particular, a GNSS signal, are delivered to a general purpose microprocessor at a rate of 8 MHz and chip sums over eight consecutive data values spaced by a sampling length (TS), each beginning with one of the data values as an initial value, formed and stored. For code removal, each of a series of chip sums covering a correlation interval of 1 ms and each essentially coinciding with a chip interval of fixed chip length (TC), where a value of a basic function (bm) reflecting a PRN basic sequence of a satellite assumes a correlation value (Bm), is multiplied by the latter and the products added up over a partial correlation interval to form a partial correlation sum. The partial correlation interval is chosen in such a way that it essentially coincides with a corresponding Doppler interval having a Doppler length (TD) where a frequency function used for tentative Doppler shift compensation and represented by a step function (sine, cosine) is constant.

Abstract: In a GNSS receiver data sequences derived from a digital signal each with an internally generated correlation sequence derived from a basic sequence and mixed with frequency signals corresponding to various Doppler frequencies and in various phase positions with respect to the data sequence are correlated and the correlation values evaluated. In difficult conditions, e.g., RF levels of the signal of ?145 dBm and less, correlation values produced with the same correlation sequence and phase position but with a plurality of data sequences are evaluated together in that, in an evaluator (49), every-correlation value is, in a comparator (52), compared with at least a first value threshold and a second value threshold, with the latter having a value between 1.3 and 1.7 times the value of the first and values ?1, 0 or +1 assigned accordingly to a correlation term which is then added to an integer correlation counter which varies over a counter interval, e.g., [0, 15], in an adding unit (53).

Abstract: An acquisition unit of a GNSS receiver base band circuit comprises an integrator (27) with a number of preprocessors (29a-h) where an incoming digital signal is mixed with different frequency signals to compensate at least in part for clock drift and Doppler shifts. The resulting digital signals are in each case, after an accumulation step reducing sample frequency, integrated over an integration period extendinging over several, e.g., twenty, basic intervals of the length of a basic sequence characteristic for a GNSS satellite, usually 1 ms, in such a way that samples separated by a multiple of the basic interval are superposed.

Abstract: For suppression of continuous wave interferers at, e.g., up to four interferer frequencies (f1, f2, f3, f4) in a GNSS receiver base band circuit a raw digital signal is, in a band stop unit (21), shifted, by a first mixer (31a), by the negative of the first interferer frequency (f1) in the frequency domain whereupon the continuous wave interferer is suppressed by a band stop filter (30a), a linear phase FIR filter with a suppression band centered at zero, e.g., a filter subtracting a mean over previous subsequent signal values from the actual signal value. After further shifting of the shifted digital signal by the negative of the difference between the second interferer frequency (f2) and the first interferer frequency (f1) the shifted digital signal is again filtered by an identical band stop filter (30b) and so on.

Abstract: An acquisition unit of a GNSS receiver base band circuit comprises a correlator (40) with a correlator shift register (43) to which a correlation sequence derived from a basic sequence characteristic for a satellite is fed by a code generator (41). Each of the N=32 or more memory cells of the correlator shift register (43) is connected to two correlator cells (44a, 44b) for multiplying digital values of the correlator sequence from the memory cell with data values of a data sequence, adding up the products and storing the sum in a register as a correlation value pertaining to one of N relative phase positions of the correlation sequence relative to the data sequence during a correlation phase.

Abstract: An analog die (3) and a digital die (4) are supported by a plate (1) consisting of an electrically conductive material. Pads (5) of the dies (3, 4) are connected to each other, to plate (1) or to pins (2) surrounding the latter by bond wires (6). The upper side of the plate (1) is covered by a plastic mold (7) encapsulating the dies (3, 4), the bond wires (6) and, in part, the pins (2). For the suppression of external jamming signals as well as internal ones picked up by bond wires the digital die (4) comprises an adjustable notch filter which suppresses narrow frequency bands where jamming signals have been detected.

Abstract: A sychronization circuit comprising an analog feedback shift register for generating an internal sequence which is synchronized with an external sequence containing repetitions of a fundamental sequence has a feedback circuit which, for the formation of a new value of a fundamental sequence, combines at least two values (x1,x2) stored in the shift register according to a feedback function (f(x1,x2)), which is then scaled with a factor k, 0.9<k<0.99. The synchronization behaviour is improved, especially in the case of signals with strong background noise, by using a feedback function which is substantially linear in the sectors defined by the signs of the arguments and whose sign corresponds to that of the negative of the product of the negative arguments and whose magnitude is 1 if the magnitudes of the arguments are each 1. A function which meets these requirements and has proved useful is f(x1, . . . , xm)=?sig((?x1)· . . . ·(?xm))·(|x1|+ . . . +|xm|)/m.

Abstract: A method for generating an internal sequence of analog values having a specific period includes producing an intermediate value by a logical combination of an actual value of the external sequence with an actual value of a second generating sequence, producing an input value to an analog feedback shift register by superposition of the intermediate value with an analog feedback value derived according to a feedback function from analog values in the analog feedback shift register, and feeding the input value to an input of the analog feedback shift register. A position of an actual value of the second generating sequence corresponds to a position of a segment in the first generating sequence, the segment including a determinative set of n binary values derived from the analog values in the analog feedback shift register.

Abstract: For allowing positioning of a GPS receiver within a building, GPS primary positioning signals received by an outdoor receive antenna are up-converted to different carrier frequencies in the 2.4 GHz ISM band and the converted signals are transmitted each by a transmit antenna inside the building, the transmit antennas serving at the same time as access points of a WLAN which is used for transmitting additional positioning data like the positions of the transmit antennas and the signal delay times associated with them. By cycling through the secondary positioning signals received from the transmit antennas, i.e., down-converting each of them during an assigned time slot, and determining clock bias differences in the receiver, the position of the latter is determined using TDOA algorithms.

Abstract: For allowing positioning of a GPS receiver within a building, GPS primary positioning signals received by an outdoor receive antenna are up-converted to different carrier frequencies in the 2.4 GHz ISM band and the converted signals are transmitted each by a transmit antenna inside the building, the transmit antennas serving at the same time as access points of a WLAN which is used for transmitting additional positioning data like the positions of the transmit antennas and the signal delay times associated with them. By cycling through the secondary positioning signals received from the transmit antennas, i.e., down-converting each of them during an assigned time slot, and determining clock bias differences in the receivers the position of the latter is determined using TDOA algorithms.

Abstract: A feedback circuit for amplification of the output signal of an analog front end and suppression of its DC and low frequency components comprises a variable gain amplification unit (2) controlled by a gain control signal and a reverse path unit (6) comprising a filter unit (8) with variable time constant. A control unit (13) produces the gain control signal as well as a reverse path control signal (S) which causes adaptation of variable resistances (12) and capacitances (10) in such a way that the time constant of the filter unit (8) varies essentially proportionally with the gain of the variable amplifier unit (2). Thereby the gain of the feedback circuit as a function of the frequency retains its shape with varying gain.

Abstract: A GPS-cellular hand-set includes a receive antenna; a separate transmit antenna; a power amplifier; a duplex filter unit having an input connected to the receive antenna, a cellular output, and a GPS output; a cellular unit having a receive input and a transmit output, wherein the receive input is connected to the cellular output of the duplex filter unit and the transmit output is connected to the transmit antenna via the power amplifer; and a GPS unit having an input connected to the GPS output of the duplex filter unit.

Abstract: A sychronization circuit comprising an analog feedback shift register for generating an internal sequence which is synchronized with an external sequence containing repetitions of a fundamental sequence has a feedback circuit which, for the formation of a new value of a fundamental sequence, combines at least two values (x1,x2) stored in the shift register according to a feedback function (f(x1,x2)), which is then scaled with a factor k, 0.9<k<0.99. The synchronization behaviour is improved, especially in the case of signals with strong background noise, by using a feedback function which is substantially linear in the sectors defined by the signs of the arguments and whose sign corresponds to that of the negative of the product of the negative arguments and whose magnitude is 1 if the magnitudes of the arguments are each 1. A function which meets these requirements and has proved useful is f(x1, . . . ,xm)=−sig((−x1)· . . .

Abstract: A GPS receiver comprises, for each satellite, synchronization circuits for local generation of an internal sequence corresponding to the external sequence derived from the received signal and synchronized with said sequence, which circuits each comprise an analog shift register (25), fed back via a feedback circuit (26), a gain block (27) and an adder (24), for generating the first of m-sequences generating a Gold sequence, and a memory (29) which contains the elements of the second generating m-sequence, which can be read out with a determinative set derived from the values stored in the shift register (25) as address. In a logic element (23), the value read out is logically combined with the next element of the external sequence for generating a value substantially corresponding to the next element of the first m-sequence, and the result is superposed with the feedback value in the adder (24).

Abstract: An active duplex filter unit (7) for a combined GPS-cellular hand-set comprises a GPS low noise amplifier unit (13) connecting a receive antenna to the input of a GPS unit. It comprises a capacitance (15) and an inductance (16) preceding, in parallel, an amplifier (14) whose output is connected to ground via, in series, an inductance (17) and a capacitance (18) with a tap (19) for the application of a bias voltage (+V) between them. A similar cellular low noise amplifier unit (12) connects the receive antenna with the recive input of a cellular unit a transmit output of which is connected to a transmit antenna via a power amplifier. The GPS low noise amplifier unit (13) provides high gain and low noise figure at the GPS frequency and strong suppression in particular of frequencies used by cellular systems. The transmitter leakage signal in the GPS and cellular receivers is attenuated by the separation of the receive and transmit antennas.