摘要:
A multi-channel spread-spectrum system separates a data stream, for example from a convolutional encoder and an interleaver, into sub-channel data-sequence signals. For each sub-channel data-sequence signal, m bits are translated to one code of a unique set of orthogonal chip-sequence signals. The other k bits of the same sub-channel data-sequence signal are translated to a distinct phasor. Each phasor is used to modulate the respective chip-sequence signal. A complex-signal combiner combines the real and imaginary components of all the phase-modulated chip-sequence signals into in-phase (I) and quadrature (Q) spread-spectrum multi-channel signals, which are spread by a cell-site specific signature-sequence. The receiver decorrelates the received spread-spectrum signal, preferably with a bank of matched filter (MF) joint-detectors, to recover the bits from all the spread-spectrum sub-channel signals for remultiplexing into the transmitted data stream. The multi-channel spread-spectrum system supports constant data rate throughout the cell by maintaining a large processing gain, at the demultiplexed sub-channel data sequence level, thus a code-reuse-one type spread-spectrum system can be deployed with the aid of power control.
摘要:
Multi-path effects are common in mobile communications. When coupled with spread-spectrum signals utilizing spreading code sequences, detection of more than one multi-path signal becomes a necessity in order to output a clean signal with little loss. In accord with the invention, a spread-spectrum sliding matched-filter searcher system comprises a partial matched-filter that receives the input spread-spectrum signal. The searcher matches samples of the input signal with a tap length m of the reference code and produces a first correlation value. The first correlation value is compared to a first threshold. When it equals or exceeds the first threshold, the first correlation value is integrated to produce a second correlation value. This second value is compared with a second threshold, which if met signifies the detection of the multi-path signal. The process is repeated until all significant multi-path signals are detected. This design of the present invention is flexible in nature because the searcher can be programmed to act like a matched-filter, a correlator, or a combination of both while significantly improving the search time and reducing the amount of hardware and complexity characteristic of a matched-filter.
摘要:
An external lens device mounted in front of an internal camera of a portable electronic device includes an external lens and a positioning mechanism. The positioning mechanism includes a fixing element defining an opening and a sliding element fixing the external lens. The fixing element is slidably mounted on the portable electronic device to enable the opening to align with the internal camera. The sliding element is slidably mounted on the fixing element to enable the external lens to align with the opening and the internal camera. A portable electronic device using the external lens device is also described.
摘要:
A system and method for managing communication of a movable entity is provided. The system comprises a chargeable power source, at least one sensor unit which is connected with the movable entity, and a global positioning device which is powered by the chargeable power source and is connected with the movable entity, wherein the global positioning device is used to track moveable entity status in response to sensor data received from said at least one sensor unit, the global positioning device is configured to execute a power saving mode based on moveable entity status information. The system and method save electric energy consumption of a battery for the GPS device by the mode switching between a sleep mode and a work mode, and judgment on the predetermined event provided may help to prevent the machine from being stolen.
摘要:
A system and method for safely managing a machine is provided. The present disclosure may conduct to determine the work condition of machine when a remote instruction is received via a mobile communication system. The received instruction may be carried out only if the machine is in a safe situation.
摘要:
A strap holding structure (200) for an electronic device (100), which includes a body (20), a cover (10). The body has a knuckle (22) formed at one end thereof. The knuckle has a middle board (226) formed therein. The cover has a barrel (12) formed at one end. The strap holding structure includes a latching element (30) and a strap holder (40). The latching element is attached to the cover at one end. The strap holder has a pole (424) at a first end of the strap holder. A groove (444) is circumferentially defined in an outer wall of the strap holder and two notches (442) are axially defined in the outer wall thereof. The strap holder is engaged in the knuckle and the barrel. The latching element is received in the groove and the middle board is received in the notches.
摘要:
A foldable electronic device (100) has at least two components hinged together by a hinge assembly. The foldable electronic device includes: a cover (10), a rotating element (20), an elastic element (30) and a frame (40), a set of magnetic elements (50) and a body (60). The rotating element has two notches defined therein. The elastic element has a latching portion. The elastic element is fixed in the rotating element. The frame slidably engages with the rotating element. The frame is engaged with the cover. The rotating element rotatably connects with the body. The magnetic elements make the cover close relative to the body. When the latching portion of the rotating element engages in different notches of the rotating element, magnetic force between the magnetic elements decreases so as to open the cover relative to the body.
摘要:
A lens cover assembly (200) mounted in an electronic device (300) includes a lens cover (30), and a frame (20). The lens cover includes a base (32), and a column (34) extending from a central area of the base. The base has at least one notch (36) defined therein. The frame has a stepped hole (26) defined by a first circumferential wall (262), a second circumferential wall (264), and a connecting surface (266) connecting the first circumferential wall to the second circumferential wall. At least two blocks (28) extend from the first circumferential wall and overlie the connecting surface. In assembly, the lens cover is received in the stepped hole. Then the base is rotated relative to the frame about an axis of the stepped hole so that the base is sandwiched between the blocks and connecting surface to lock the lens cover in the frame.