Abstract:
An apparatus (101, 110) and method for adaptive forward error correction in a data communication system (100) provides for dynamically changing forward error correction parameters based upon communication channel conditions. Data having a current degree of forward error correction is received (305), and a channel parameter is monitored (310). A threshold level for the channel parameter is determined (315), and the monitored channel parameter is compared to the threshold level (320). When the channel parameter is not within a predetermined or adaptive variance of the threshold level, a revised forward error correction parameter having a greater or lesser degree of forward error correction capability is selected (330, 340, 350, 360), and the revised forward error correction parameter is transmitted (370). The device receiving the revised forward error correction parameter, such as a secondary station (110), then transmits data encoded utilizing the revised error correction parameter (425).
Abstract:
A transition metal oxide based calorimetric non-methane hydrocarbon sensor (100) is constructed by disposing a transition metal based catalyst (105), preferably chromium oxide (Cr2O3), onto a carrier (101). A temperature measurement device (103) is positioned thermally coupled to the transition metal based catalyst (105).
Abstract translation:基于过渡金属氧化物的量热非甲烷烃传感器(100)通过将过渡金属基催化剂(105)(优选氧化铬(Cr 2 O 3))设置在载体(101)上而构成。 温度测量装置(103)被热耦合到过渡金属基催化剂(105)上。
Abstract:
A cable communication system (100) where a control unit (110) sends operation parameters to subscriber units (130) and the subscriber units (130) respond by modifying the method of communication. Also, the subscriber units (130) send messages which include information on the subscriber unit (130) and the capabilities of the subscriber unit (130). Furthermore, the control unit (110) efficiently manages the system (100) by monitoring the capabilities and instructing the subscriber units (130) on how to communicate on the system (100). Such management allows for the migration of subscriber units (170) from one service area (140) to another (190) without the disruption of service. In addition, initialization of subscriber units (130) may be accomplished over the cable and does not require an operator at the subscriber location.
Abstract:
Power control in a spread spectrum communication system takes place by determining a speed of a remote unit (405) and assigning as a power-control threshold a target threshold based on the determined speed (410). An instantaneous threshold value is created (415) based on frame-quality information and the target threshold. An energy of a power-control group transmitted (430) from a remote unit is compared to the instantaneous threshold value and a power-adjustment command is determined. The power-adjustment command is transmitted to the remote unit instructing the remote unit to adjust its power accordingly.
Abstract:
A wireless communication system (200, 300, 400, 500) mitigates the effects of excess timing delay caused by varying lengths of communication paths. In one general implementation, a transition communication path (206, 323, 329) is used to transfer a time-advanced version of a timing reference signal so that the cumulative time delay at a transition cell (209, 325, 331) is reduced. In another general implementation, the timing reference signal is time-advanced in all communication paths (403-411), and selected communication paths (403-407) include a time delay means (423-427, 503-507) such that the cumulative time delay at an area (421) near a target coverage area (130) is reduced. By reducing the cumulative time delay at the area (421) near the target coverage area (130), a hand-off of a communication of a mobile station (128) into the target coverage area (130) can be performed.
Abstract:
A two way selective call receiver (1) comprising a combined transmitter and receiver circuit (2), for receiving a coded transmitted message, and a processor (3) for determining if the message is a preview message of a longer message. The selective call receiver (1) also comprises a memory (4), display (5) and keypad (6). Upon receipt of a signal from the keypad (6), the processor (3) provides an encoded request signal to transmitter and receiver circuit. The request signal is used to request, from an information system, the longer message associated with the preview message.
Abstract:
A piezoelectric transformer (10) operating in a thickness-shear vibration mode (26). The piezoelectric transformer (10) comprises a lithium niobate substrate (12) having first and second acoustically coupled portions (16, 22), and a plurality of substantially opposing pairs of primary and secondary electrodes (14, 20) disposed thereon. An input AC voltage applied to the primary electrode pairs (14) exciting a thickness-shear vibration (26) which couples to the secondary electrode pairs (20) producing an output AC voltage therebetween. The primary and secondary electrodes (14, 20) being electrically connected in various combinations of parallel and series connections to provide a desired step-up or step-down voltage transfer ratio.
Abstract:
A self initialized coder and method thereof, the coder arranged and constructed for decoding an information stream (217), the coder including a buffer (301) for storing a portion (403) of the information stream, a controller (313) coupled to the buffer (301) for temporally reversing a first part (401) of the portion to provide a file header (415), and an adaptive decoder (213) having a state parameter, the adaptive decoder (213) coupled to the controller (313) and the buffer (301), for decoding the file header (415) to provide an estimate of the state parameter and thereafter for decoding, using the estimate, the portion (403) to provide a decoded signal.
Abstract:
A mounting for use with a ballast for powering one or more fluorescent lamps. The mounting includes a base (10), a back plate (12), and a lock structure comprising a male member (18) and a female member (20) for locking the base (10) to the back plate (12). The base (10) has at least one key (16) extending away from the base (10), and the back plate (12) has at least one key port (22) that is adapted to receive the key (16) and is configured to allow the key (16) to be positionally adjusted with respect to the back plate (12). In a preferred embodiment, the mounting has two keys (14, 16), two key ports (22, 28), and a cover (48).
Abstract:
A speech analyzer (107) compresses a voice message for transmission and includes an LPC analyzer (406) which derives spectral vectors from segments of speech; a memory (1910) which stores predetermined spectral vectors identified by indexes, the indexes also identifying predetermined voicing vectors stored within a receiver; a quantizer (422) which compares the spectral vector derived with the predetermined spectral vectors to select one of the predetermined spectral vectors; and an output buffer for storing the index identifying the predetermined spectral vector selected. The speech analyzer (107) also includes a pitch determiner (414) which includes a pitch function generator (414) which generates a pitch function from a segment of speech. A pitch enhancer (1116) enhances the pitch function of a current segment of speech utilizing the pitch function of one or more sequential segments of speech and a pitch detector (1118) detects the pitch of the current segment of speech.