Abstract: A digital demodulator includes: a local oscillator for generating a predetermined frequency signal; a mixer for mixing an intermediate frequency (IF) signal with a local oscillation frequency signal output by the local oscillator; an A/D converter for converting a signal output by the mixer into a digital signal; an I and Q signal generator for producing I and Q signals from an output of the A/D converter; and a compensation unit for compensating the signals I and Q for phase errors.

Abstract: An MPEG-2 transport stream packet detection device includes a controller for generating a detection start control signal and a series/parallel output control signal, and a sync detector for detecting an MPEG-2 transport stream packet sync from MPEG-2 transport stream data transmitted from the network according to the detection start signal from the controller, and a packet counter for counting a predetermined number of bytes according to a sync detection signal from the sync detector and sending a packet reception completion signal to the sync detector when finishing counting the predetermined number of bytes during a declaration of the detection signal, and a bit counter for counting a predetermined number of bits according to the sync detection signal from the sync detector and generating a signal for converting series data to parallel data when finishing counting the bits during the declaration of the detection signal, and a buffer for converting the series data and clock from the sync detector into parall

Abstract: A telephone service system in an ATM private network, includes: a PSTN interface unit for performing PCM with an analog telephone signal transmitted from a channel in a PSTN, converting the modulated data into a CEPT frame before sending it to a subscriber, performing the PCM with CEPT frame data, from a subscriber, and converting the modulated data into an analog telephone signal, before forwarding it to the PSTN; a first ATM cell processing unit for converting the CEPT frame data from the PSTN interface unit into an ATM cell, converting an ATM cell from a subscriber into CEPT frame data, and sending it to the PSTN interface unit; an ATM switching unit for switching the ATM cell from the first ATM processing unit to the subscriber, and switching the ATM cell from the subscriber to the PSTN; a second ATM processing unit for converting the ATM cell from the ATM switching unit into CEPT frame data before sending it to the subscriber, and converting the CEPT frame data from the subscriber into an ATM cell before

Abstract: The present invention discloses a parity detection device and method in a CDMA mobile communications system, which detects parity error in data output from a cell site modem (Q51601-2S1), and controls the data output when the parity error occurs, to improve the reliability in data communication. The invention converts serial data to be transmitted through a CSM into parallel data, checks if there is a parity error in the parallel data, and generates an interrupt when a parity error is detected. When the interrupt is generated, an output controller restrains the transmission of the serial data to be transmitted, which is outputted from the CSM, thereby preventing data having error from being transmitted.

Abstract: A method for loading sub-processors in system having a plurality of sub-processors connected with main processor via a repeater and utilizing broadcasting function is disclosed. The method comprises the Steps of inspecting a transfer path communicating the main processor and the plural sub-processors; collecting a loading request signal transmitted from the sub-processors at predetermined time period; and loading simultaneously the sub-processors using broadcasting function after interconnecting the sub-processors which request the collected loading during the collecting Step with the main processor via the repeater in multipoint base. The sub-processors having the collected signal are simultaneously loaded using broadcasting function, it has the effect for reducing loading time.

Abstract: An improved grid moving method using a selective pixel search method and an apparatus using the grid moving method which are capable of forming a grid with respect to an image of an object having a shape information and/or an image information, defining a unit region, moving the thusly formed grid, re-constructing an image grid, so that it is possible to reduce the number of blocks which are occupied by an object to be coded, thus significantly reducing the amount of computation and increasing a computation speed.

Abstract: A device for testing the link power control in a mobile communications system includes: a first device including an attenuator whose attenuation factor is controllable; a base station transmitting data through the attenuator; a mobile receiving the data transmitted from the base station through the attenuator; a first cable for connecting the transmission terminal of the base station to the input terminal of the attenuator; a second cable for connecting the output terminal of the attenuator to the reception terminal of the mobile; and a third cable for connecting the reception terminal of the base station to the transmission terminal of the mobile, the first device being for testing the forward link power control; and a second device including an attenuator whose attenuation factor is controllable; a mobile transmitting data through the attenuator; a base station receiving the data transmitted from the mobile through the attenuator; a fourth cable for connecting the transmission terminal of the mobile to the

Abstract: A method for selecting traffic channels of a mobile telecommunication base station is disclosed. Normal traffic channel elements and busy traffic channel elements are calculated and compared with each other, and a judgment is made as to whether there is a usable traffic channel element. Busy traffic channel elements of respective shelves are compared with each other to select a shelf having smallest busy traffic channel elements. Busy traffic channel elements of the selected shelf are compared with normal traffic channel elements of the same shelf, to judge as to whether there is a usable traffic channel element. A termination condition is incremented by 1 upon finding a usable traffic channel element, and a judgment is made as to whether the selected shelf index is smaller than a last shelf index. The channel card index is updated, and the self index is incremented by 1 upon finding the selected shelf index to be smaller than a last, and confirming the sequential selected shelf index.

Abstract: The FIR (Finite Impulse Response) filter with non-symmetric frequency response characteristics; data stored in the shift register is selected by the select signal to be outputted from the multiplier. The tab coefficient stored in the tab coefficient generator is outputted through the multiplier according to 2 bit select signal to be multiplied. The multiplied to be output signal is stored in D flip-flop at the rising edge of a second clock 2. The data stored in a D flip-flop is selected by the select signal to be added in the adder. The adding result is that just one fourth of the tab number is added. Therefore, this one fourth of the adding result is to be stored in D flip-flop first in order to add the rest of three fourths in the same process. 90.degree.-transited quota Qout) can be produced storing all tabs added in this way of four steps in respective D flip-flops and adding all tabs in the adder finally.

Abstract: GPS satellite signals are received, and a C/A code is synchronized by utilizing the non-coherent DLL so as to remove the unique code of the GPS satellite. There are generated 1/2-bit lagging, 1/2-bit leading and normal satellite codes. Then a correlation between the former and a down-converted intermediate frequency signals is carried out. Mixers mix the correlated three different phase signals with signals of a local oscillator. The output signals of the mixers are filtered by a band filter, and envelopes are detected from the filtered signals by an envelope detecting section. The detected envelopes are subtracted from each other. The output signals of the subtractor are filtered by a loop filter, and the filtered signals are controlled by a voltage control oscillator. The oscillated signals are inputted as clock signals into a satellite code generating section.

Abstract: A traceback device of a trellis decoder including a memory for storing survivor path information as much as a decision depth, a multiplexing unit for decoding the survivor path information received from the memorizing unit, and a traceback unit receiving the survivor path information of lower bits decoded by the multiplexing unit and state output of itself, to carry out a state transition and trace back the decoded value of lower bits.

Abstract: An output signal measuring apparatus for a multiple frequency oscillator device and output signal measuring and correcting methods therefor which are capable of accurately and rapidly measuring a signal from each terminal of a multiple frequency oscillator device and minimizing a measuring and correcting time by automatically performing a correction required for a measurement. The apparatus is capable of measuring each terminal of a multiple frequency oscillator based on a switching circuit in accordance with control of a computer by integrating a plurality of measuring equipment into one system for satisfying a corresponding measuring item with respect to all terminals of the multiple frequency oscillator, automatically correcting with respect to each such terminal, and accurately and rapidly measuring each terminal of the multiple frequency oscillator by using a predetermined time and manpower, thus implementing mass production.

Abstract: A trellis decoder uses a branch metric unit, an ASC unit, a maximum likelihood value detector, and a normalization unit in common by time-division method to realize a trellis coding interleaver used in a DTV. The trellis decoder includes path memories, state metric memories and traceback units each as many as required in the trellis coding interleaver.

Abstract: In an error data removing apparatus and method by decoding delay in a DTV system which employs a decoder of the VSB standard, respective segments or respective fields are divided into area 1 and area 2 using a starting point of decoded data as a reference to provide the decoded data of said area 1 section without involving delay and provide the decoded data of said area 2 section by delaying as long as a sync signal. A memory is utilized as the decoded data delay apparatus, and at this time, a value of a counter used for generating an address for reading/writing of the memory is utilized to delay the segment sync signal and field sync signal as required without separately using flip-flop or memory.

Abstract: A frequency gain display apparatus for an L/C band frequency up unit which is capable of generating a pulse for adjusting the gain of an L/C band frequency up unit used in a satellite system and a pulse for selecting a band width of a SAW (surface acoustic wave) filter and is capable of displaying a gain step of the same.

Abstract: A method and apparatus for separating picture image areas in facsimile machines, scanners, and other picture processing equipment, and more particularly to a method and apparatus for separating picture regions by extracting features of graphic image and characters includes a vertical contouring circuit for producing vertical contour data by combining vertical components of an original picture and binary picture data; a horizontal contouring circuit for producing horizontal contour data from horizontal components of the binary picture data; a logic combiner for combining outputs from the vertical and horizontal contouring circuits and a halftone picture; a mode discriminator for selecting between a binary picture and contouring mode; an image area separator for separating image areas with an output from the logic combiner and a halftone picture, and a counter for executing pixel counting from a halftone picture to determine the probability of the presence of a character.