摘要:
A mobile communication system is provided with a system for frequency correction in a reception apparatus which has a first control system, device or loop for detecting a frequency discrepancy in received signals and for appropriate correction of the frequency supplied to a mixer stage, and a second control system, device or loop for detecting a frequency discrepancy in received signals and for subsequent computerized correction thereof on the basis of the CORDIC algorithm.
摘要:
An arrangement and a method for synchronizing a signal processing apparatus with a received signal which has a characteristic signal content are disclosed. The arrangement has a first control loop which readjusts the signal processing apparatus with respect to the characteristic signal content on a content basis, and a second control loop which readjusts a flow control device in the signal processing apparatus with respect to the times at which the characteristic signal content appears, the first control loop and the second control loop being coupled such that a unique association is achieved between the position of the characteristic signal content in the received signal and the associated appearance time.
摘要:
An interchangeable lens (1) with a locking device (2, 2′) for system cameras is described, wherein an orientation marking (4) for mounting the locking device (2, 2′) on the camera is provided at the end of the lens housing (3) facing the camera, and the contact surface (6) of the locking device (2, 2′) has a latching depression (8) at a distance from the orientation marking (4) counter to the direction (7) of rotation of the locking operation and the contact surface (6) contains at least two, preferably six, surface areas (10) which are situated next to one another in an isolated fashion at a distance from the latching depression (8) counter to the direction (7) of rotation within an angle segment of from 100° to 160°, preferably 110° to 150°, and can be detected individually by optical means.
摘要:
A sequence of unfiltered channel estimation values xk is determined in a method for calculation of filtered channel estimation values dk in radio systems. A specific set of filter coefficients is selected from two or more filter coefficient sets, with the filter coefficients being calculated on the basis of the MMSE optimality criterion for a predetermined recursive digital filter (F). The sequence of unfiltered channel estimation values is then filtered by means of this recursive digital filter (F) using the selected filter coefficients.
摘要:
The invention relates to an apparatus for preprocessing of pilot symbols for channel estimation. The pilot symbols are transmitted from a base station and are received by a mobile radio, and are available in the mobile radio. The apparatus includes a low-pass filter apparatus for filtering the received pilot symbols, with a setting of the low-pass filter apparatus depending on the relative speed of the mobile radio with respect to the base station.
摘要:
A device for exposure metering in photographic cameras including a reflector located in the imaging beam path. The surface of the reflector is provided with a reflecting structure whose size corresponds at least approximately to that of the image recording format. At least one photoelectric receiver records the light intensity of a portion of the image reflected from the reflecting structure. The reflector is pivotally mounted in the camera housing such that during exposure metering the reflector surface is in the vicinity of the film plane of the camera. A limited portion of the reflector is transparent and a photoelectric receiver is set into the backside of the reflector behind the transparent portion.
摘要:
The invention relates to a transmitting and receiving arrangement for radios having a baseband component and a radio-frequency component that are connected via an interface for interchanging payload data. The interface includes a bidirectional data link that can be operated in a half-duplex mode for transmission of digital payload data to be transmitted from the baseband component to the radio-frequency component and for transmission of received digital payload data from the radio-frequency component to the baseband component.
摘要:
A hardware apparatus (10) for conditioning pilot symbols for channel estimation in a mobile radio comprises a time-division multiplexed low-pass filter unit for filtering the received pilot symbols. The time-division multiplexed low-pass filter unit comprises, between its input and its output, a feedback path which can be switched in and which can be used to implement a plurality of filter stages in a time-division multiplexed arrangement.
摘要:
The present invention provides a method for prediction of a channel coefficient for a propagation path in a mobile radio channel with multipath propagation, in which a canonical random variable analysis is used for prediction of the channel coefficient. The method is preferably used in an estimator for channel coefficients in a base station or in a mobile station in a mobile radio system.
摘要:
A comparator unit is used to compare an actual transmission time signal with a nominal transmission time signal and to produce a difference signal from the discrepancy, from which difference signal a correction signal is produced in a control unit. This correction signal is used to control a correction unit, which compresses or extends an applied input data signal, thus changing the phase angle of the output data signal so as to minimize the discrepancy between the transmission times. The discrepancy is corrected independently of the system clock, and the correction speed is set variably.