Abstract: The present invention provides an apparatus and method for determining the quality of a digital signal (S). The incoming digital signal (S) is sampled with a number n of samples per defined pulse width, whereby n≧1, using clock cycles (CLK). In the following, an edge detector (20) detects the edge position of a pulse of the sampled digital signal and a counter (30) counts the clock cycles between at least a first edge and a second edge detected by the edge detector. A deviation detector (40) then compares the counted clock cycles (EEC) with a prestored reference-value (EEC0) in order to provide a deviation value (RJ) as a measure for the instantaneous quality of the digital signal (S). This deviation value (RJ) is then fed to a rework unit that outputs a value (J) that is a measure for the quality of the digital signal.

Abstract: The present invention provides an apparatus and a method for determining a pulse position for a signal encoded by a pulse modulation. The signal being receivable as at least a first component (PCS) and a second component (DCS). A first storage unit (102) stores at least one symbol of the first component (PCS) and a second storage unit (104) at least one symbol of the second component (DCS). A determination unit (118) comprises a probability table (110), which in case that the first and second components (PCS, DCS) are received is addressed with the at least one symbol of the first component (PCS) and the at least one symbol of the second component (DCS). Thereby, the probability table (110) provides a value that is defined as the pulse position (DDS).

Abstract: A packet-frame generator for creating an encoded packet frame comprising encoded control data and encoded utilizable data. A non-encoded packet frame comprising non-encoded control data and non-encoded utilizable data is providable by an assembling means. The packet-frame generator comprises a modulation encoder for encoding the non-encoded control data by a first modulation code and the non-encoded utilizable data by a second modulation code thereby providing the encoded packet frame.

Abstract: A method and means for reducing high-duty-cycle unconstrained binary signal sequences in storage and communications processes and systems by invertibly mapping such sequences into a (1, k) rate ⅔ RLL codestream constrained to a duty cycle substantially approximating one-third. That is, binary sequences ordinarily mapping into high-duty-cycle RLL-code sequences are either inhibited from repeating indefinitely or excluded.

Abstract: The invention is family of noise predictive maximum liklihood (NPML) symbol detectors that are particularly useful in direct access storage devices. Various embodiments representative of the family of detectors are described. In general, the NPML detectors include a sequence detector with imbedded feedback which may be preceded by a filter, e.g., a prediction error filter. The sequence of detectors, which may be Viterbi detectors, have an imbedded filter whose coefficients are determined by the convolution of the partial response (PR) or generalized PR function with the predictor coefficients and do not require multiplications and, thus, allows a simple RAM look-up for intersymbol-interference ISI cancelation. In one class of embodiments, the NPML detector comprises a prediction error filter of length N, cascaded with a sequence detector having 2.sup.

Abstract: A method and apparatus are provided for data detection for a partial-response maximum-likelihood (PRML) data detection channel in a direct access storage device. A class-IV partial response (PR4) signal is applied to a PR4 Viterbi detector to provide a PR4 Viterbi output and is applied to a first matching delay circuit to provide a delayed PR4 signal. The PR4 Viterbi output is subtracted from the delayed PR4 signal and a resulting signal is applied to a first filter having a frequency response of 1/(1-.alpha.D.sup.2). The filtered output signal is applied to a second filter providing a second filtered output signal. The PR4 Viterbi output is applied to a second matching delay circuit to provide a delayed PR4 Viterbi output signal. The delayed PR4 Viterbi output is corrected responsive to the second filtered output signal. The first filter is an infinite impulse response (IIR) filter and the filtered output signal represents whitened noise and modified PRML error events.

Abstract: The wireless communication system, comprising a transmitter and a receiver, operates according to the present PPM-FSK modulation format with two subcarrier frequencies f.sub.1 and f.sub.2. The PPM encoded data on the main data channel 43 are fed to two pulse shaping circuits (30, 31) for additional frequency modulation with said frequencies. The resulting hybrid PPM-FSK signal is used to drive a light source (32). The receiver comprises a photodiode (34) coupled to an amplifier (35). The electrical signal obtained at the output of the amplifier (35) is fed to bandpass filters (36, 37) and envelope detectors (38, 39). The outputs of the envelope detectors are fed to a device (40) designed for pulse restoration and frequency decision. In a first operation, device (40) uses the output signals of the two envelope detectors (38, 39) to derive from them the estimated PPM encoded data signal. It then uses this signal to produce estimated restored pulses and outputs them.

Abstract: A method and apparatus are provided for maximum-likelihood data detection in a partial-response (PR) data channel including a head and disk assembly providing an analog signal coupled to an analog to digital converter (ADC) providing digital samples. A plurality of digital samples are received from the ADC. The received digital samples are applied to a selected first filter and a selected second filter. The first filtered digital samples are applied to a first data detector, and the second filtered digital samples are applied to a second data detector. A predetermined parameter is identified, and at least one of the first and second data detectors is selected responsive to the identified predetermined parameter.

Abstract: Apparatus and method for providing equalization adjustment for a filter are provided in a PRML data channel. A first predetermined test pattern is written. Relative error is measured in both magnitude and phase for predetermined frequencies. A relative magnitude ratio for the predetermined frequencies and a phase delay between the predetermined frequencies are identified. A tap set is generated having predefined frequency responses at a plurality of predefined discrete frequencies.

Abstract: In the readback apparatus of magnetic recording system operating in accordance with the partial-response maximum-likelihood (PRML) technique, a variable-gain amplifier (VGA) and a maximum-likelihood sequence detector (ML DET) plus a gain control loop are provided. The detector (19) is designed to operate on input signals (y') having nominal discrete signal amplitudes (a, 0, -a) and it furnishes discrete output signals (y) having such nominal signal amplitudes. The gain control loop is responsive to input (27) and output (29) signals of the detector, and it has charge-pump circuitry (37, 39, 41, 43) for generating a gain control signal (V.sub.c =V.sub.g) for the variable gain amplifier (35).

Abstract: The supporting means for a baffle used to close a mould of a glassware forming machine comprises an arm (12) mounted for vertical movement and for movement about a vertical axis. A support (14) is mounted on the arm and a baffle holder (28) is mounted on the support. The baffle holder is mounted on the support for limited vertical movement relative thereto against the action of resilient means (32) and also for limited movement in a horizontal plane.

Abstract: A take-out mechanism for removing articles of glassware from a glassware forming machine comprises an arm turnable about a horizontal axis, a support (10) mounted on the arm, orientating means to maintain the orientation of the support as the arm turns, a tong carrier (14) and securing means securing the tong carrier to the support. The securing means comprising mating portions (10b,14b) having mating surfaces (10c,14c) and at least one projection (18) arranged to enter a recess (20) so that the surfaces can only mate in a particular desired orientation, and a screw (22) captive in the carrier and arranged to enter a threaded recess (24) in the support.

Abstract: Neck ring half (18,20) supporting arms (14,16) are mounted on carriers (10,12) therefor, in a parison transferring mechanism of a glassware manufacturing machine, by providing a stop (40) on each carrier at a predetermined height (x) relative to an axis (24) about which the carriers turn to move the neck ring halves and hence the parisons. As an arm slides into a mounting therefor on the carrier, a heightwise adjustable stop (44) on the arm contacts the stop (40) and thereby determines the height of the arm. Adjustment of the stop (44) on the arm can be carried out away from the machine so that machine down-time can be reduced.

Abstract: An operative member such as a blowhead (10) is moved between an out-of-the-way position thereof and an operative position thereof by moving means which comprises a vertical shaft (15), means for moving the shaft vertically and turning it about a vertical axis (14), and a support (18) for the operative member clamped to the shaft. The support (18) comprises an arm (20) on which the member is mounted and clamping means (30,34,38,40) to clamp the support to the shaft. Complementarily-shaped camming surfaces (22 and 36) of the shaft and the support urge the support into the correct orientation with respect to the shaft.