Abstract: A method for determining if a signal received at a radio receiver in a communication system is transmitted to the receiver via a direct radio link comprising the steps of: determining a signal characteristic based on one or more signal measurements collected at the receiver; comparing the signal characteristic as determined with at least one predetermined system parameter; and responsive to said comparison determining if said signal is received via a direct link.

Abstract: A method of controlling a satellite communication system, a timing unit, and a control unit of a timing unit. The method comprises dividing the coverage area of the satellite communication system into one or several geographical areas; positioning one or several timing units in at least one geographical area; determining which of the satellites of the satellite communication system are visible in each particular geographical area; controlling the timing unit with a control unit, in order to minimize the time difference within the system, to listen to one or several satellites visible in each particular geographical area, the signals received from the satellites by the timing unit fulfilling a predetermined condition; synchronizing a predetermined number of geographical areas with each other by means of the control unit of the system such that the time difference within the system is minimized in a predetermined combination area of geographical areas.

Abstract: A method for calculating the location of a mobile user terminal in a wireless communication system, comprising the steps of: identifying a default sequence in which a plurality of location calculating methods should be executed to calculate said location; forming a new sequence by reordering said default sequence responsive to at least one system parameter; and executing at least one of said calculating methods in accordance with the new sequence to thereby calculate said location.

Abstract: A method for determining if a signal received at a radio receiver in a communication system is transmitted to the receiver via a direct radio link comprising the steps of: determining a signal characteristic based on one or more signal measurements collected at the receiver; comparing the signal characteristic as determined with at least one predetermined system parameter; and responsive to said comparison determining if said signal is received via a direct link.

Abstract: A method for calculating the location of a mobile user terminal in a wireless communication system, comprising the steps of: identifying a default sequence in which a plurality of location calculating methods should be executed to calculate said location; forming a new sequence by reordering said default sequence responsive to at least one system parameter; and executing at least one of said calculating methods in accordance with the new sequence to thereby calculate said location.

Abstract: The present invention relates to a location method and system for locating a wireless terminal device (10) in a cellular network. At least two spatially diverse local measurement units (41-43) are arranged at a local determination unit (20) and adapted to receive a signal from the wireless terminal device (10). Measurement signals received from the at least two local measurement units (41-43) are processed at said local determination unit (20) to obtain a location information of said wireless terminal device (10) to be transmitted to a location center of said cellular network. The location information may be a time difference of arrival value or a location estimate. Thereby, a high accurate location can be provided in specific areas, such as indoor environments. Furthermore, network signaling load is reduced and clock synchronization between location measurement units is no longer required, due to the fact that the location information is directly generated at the local location measurement units.

Abstract: A method of controlling a satellite communication system, a timing unit, and a control unit of a timing unit. The method comprises dividing the coverage area of the satellite communication system into one or several geographical areas; positioning one or several timing units in at least one geographical area; determining which of the satellites of the satellite communication system are visible in each particular geographical area; controlling the timing unit with a control unit, in order to minimize the time difference within the system, to listen to one or several satellites visible in each particular geographical area, the signals received from the satellites by the timing unit fulfilling a predetermined condition; synchronizing a predetermined number of geographical areas with each other by means of the control unit of the system such that the time difference within the system is minimized in a predetermined combination area of geographical areas.

Abstract: For synchronous transmission between two telecommunications units, the devices must always be synchronized. Typically, a reference signal is required for synchronization. The reference signal can be transmitted from one unit to another embedded in the data signal. If the data is transmitted via a transmission network modulated in the way required by the network, the reference signal is not always received by the receiver together with the data signal. The problem is solved by this invention by converting the reference signal before its transmission into the transmission network for the frequency band used for transmission in the transmission network.

Abstract: A receiver for spectrum analysis includes at least one mixer in which a radio frequency input signal to be measured is mixed with an oscillator frequency generated by a voltage-controlled oscillator. In a detector, the level of an input signal to be measured is detected, after the signal has been transferred onto a lower frequency. The use of a logarithmic amplifier may be avoided by directing the detected signal to a decision means, which, in response to a change in the level of the detected input signal, provides a control voltage proportional to the magnitude and the direction of the change. The voltage commands an adjustable attenuator to attenuate the signal to be measured so that the level of the detected input signal substantially remains constant. The attenuation of the attenuator measured in decibels is linearly dependent on the control voltage, so that the values of the control signal directly represent the amplitude values.