Nokia Mobile Phones Limited

Tero Kuusinen

Kjell Ostman

The object of the invention is a method and a circuit arrangement for the processing of a signal in connection with its reception, when the signal conforms to one or more system specifications. The invention is preferably applied in receivers operating on two frequency ranges or in receivers intended to be used in two radio communication systems. Preferably the receiver is a part of a mobile station or a base station of a cellular system. An inventive idea is that before the analog-to-digital converter (324) the intermediate frequency signal (IF1, IF2) is processed on a wide band (310, 320) so that both the narrow band signal and the broadband signal are on the pass-band of the signal line. Then, when a narrow band signal is received, the signal also contains signals outside the band of the payload signal. Then the analog-to-digital conversion (324) is performed on a conversion range with a sufficiently wide conversion dynamics, so that also the signals outside the band can be converter without causing distortion components on the received band. The bandwidth is eventually restricted by digital signal processing (326). In a receiver according to the invention it is not necessary to filter the signal depending on its bandwidth, so there is no need for intermediate frequency filters for each system.

Method and a circuit arrangement for the processing of received signals

The invention concerns a method and circuitry for compensating internal timing errors of a mobile station, particularly those of a digital mobile station. According to the invention, the signal samples that include the maximum amount of energy and the position signals (maxpos) of these maximum signal samples are, by means of a correlator (8), determined from a channel impulse response estimated in a way known in the art, and in a timing unit (6), with help of successive position signals (maxpos), a correction signal is determined that indicates the magnitude and direction of the timing error of the mobile station, and by said correction signal the ting of the mobile station and particularly that of its clock system is checked and, if necessary, synchronized.

Method and circuitry for compensating internal timing errors of a mobile

A decoding method and circuit takes into consideration two different techniques of using offset words in error correction coding by subtracting the offset word in a parallel mode from a calculated syndrome. In an error correction decoder (36) an entire incoming data block (26 bits, where 16 are data and 10 are parity) is read into a polynomial divider (11). The invention enables a single data receiver (30) to operate using error correction offset, words A, B, C, and D, in a first radio data system, or the offset words A, B, C, D, and E, in a second radio data system. In accordance with an error correction decoder of this invention the decoder is arranged with a parallel-bit output offset counter (13), an offset word generator (16), and a syndrome storage register (15) coupled to the polynomial divider (11) for enabling the subtracting of an offset word, in parallel, from calculated syndromes.

Error correction decoder that operates in either ARDS system or a RBDS

The invention comprises a digital detector used in a paging system. This detector has reference levels, against which the received signal is compared with a digital comparator (11). The reference levels can be changed with an updating logic (12), if changes are observed in the levels of the received signals. The detector may also compensate for differences between individual FM detectors.

Growing community of inventors

Turku, Finland

Tero Kuusinen