摘要:
This invention provides a method for bit detection of the GFSK signals at the receiver end. The bit detection is done digitally after the carrier is removed. It employs differential detection incorporated with decision feedback, which uses previous one (so-called on-bit differential detection), or two (so-called two-bit differential detection) bits as correcting information. In addition, synchronization for bit timing and frequency offset resulted from clocks between the transmitter and receiver are also performed with or without preamble as prior information. If preamble is available, the bit timing and frequency-offset bias are estimated from the preamble, which is the case of this present invention. If preamble is not available, this information is estimated directly from the unknown received signals. Once the information about the bit timing and frequency offset is obtained, it is used for the following bit detection.
摘要:
An avoidance method for co-channel interference in a wireless network. The first step of the method is to evaluate an interference measure on each subcarrier. Based on the interference measure of each subcarrier, a peak-to-average measure ratio of interference within the received symbol is then obtained. If the peak-to-average measure ratio of interference is greater than a predetermined threshold, a most interfered subcarrier at which the maximal interference measure occurs is detected. Accordingly, a downgrading factor is set for the most interfered subcarrier.
摘要:
A channel quality assessment with short assessment time and good frequency resolution is disclosed. Some channels are grouped and their detecting results are collected as whale to determine the channel quality. The channel quality is determined by interference collision ratio, which is the ratio of the number of interference events to the sum of the number of interference events and interference-free events. Interfered channels are disabled form the group. The Channel quality of each of plurality of channels is determined from detection results of each of plurality of groups so as to have a short assessment time and meanwhile a good frequency resolution may be retained.
摘要:
A selective hopping method for hit avoidance in a frequency hopping spread spectrum communication system utilizing an original hopping sequence, having a plurality of available channels for receiving signal packet traffic utilizing a plurality of receiving signal slots are disclosed. The plurality of available channels all are available for use in frequency hopping. The method includes the steps of dividing the plurality of available channels into a plurality of partitions; distributing the available channels in each of the plurality of partitions into a predetermined distribution; forming a partition sequence by assigning a predetermined number of channels to a plurality of selected receiving signal slot sets; generating a generated hopping sequence by partition mapping, in which the partition mapping is responsive to the partition sequence; and managing the receiving signal packet traffic, in which the receiving signal packet traffic is transmitted only in the selected receiving signal slot sets.
摘要:
A method and an apparatus for determining a hopping sequence for selecting a channel from a plurality of channels divided into a plurality of partitions to reduce probability of data collision in a frequency hopping spread spectrum (FHSS) communication system are provided. The communication system stores multiple predetermined partition sequences and receives a first sequence generated by a convention sequence generator.
摘要:
This invention discloses a display device mother substrate, a display device substrate and a manufacture method of display device substrate thereof. The display device mother substrate includes a first substrate, a second substrate, a first active area circuit and a first transmission line, wherein a first cutting line is defined between the first substrate and the second substrate. The first active area circuit is disposed on the first substrate and is electrically connected to the first transmission line. The first transmission line includes a display line portion, an end line portion and a middle line portion, wherein the display line portion is electrically connected to the first active area circuit. The middle line portion is disposed on the second substrate, wherein two ends of the middle line portion are electrically connected to the display line portion and the end line portion respectively at the first cutting line. The display device mother substrate is cut along the first cutting line to be separated into the first substrate and the second substrate, wherein the middle line portion is also separated from the display line portion and the end line portion.
摘要:
A robust timing offset compensation scheme for multi-carrier systems. According to the invention, a timing offset compensator is provided to compensate a current symbol in the frequency domain for the effect of timing offset with a timing offset prediction value. Then a timing error estimator calculates a timing error value for the current symbol based on a function of a phase tracking value, a channel response of each pilot subcarrier, transmitted data on each pilot subcarrier, and a timing compensated version of the current symbol on the pilot subcarrier locations. Furthermore, a timing tracking unit receives the timing error value of the current symbol to generate a shift amount of the DFT window and the timing offset prediction value for a next symbol.
摘要:
An OFDM detection apparatus and method for networking devices. First, a sample sequence is taken from the beginning of a newly arrived network packet. Next, a first correlation sequence between the complex conjugate of the sample sequence and the sample sequence with a lag of N samples is formed. In the meantime, a second correlation sequence between the complex conjugate of the sample sequence and the sample sequence with a lag of M samples is also formed. The first and the second correlation sequence are then normalized. Depending on a comparison between the first normalized correlation sequence and a first predetermined threshold as well as another comparison between the second normalized correlation sequence and a second predetermined threshold, the newly arrived network packet is determined accordingly whether it is an OFDM modulated packet.
摘要:
The invention discloses a finite impulse response (FIR) filter for processing a digital input signal to generate a digital output signal. The FIR filter has a tap amount N and a decimation ratio D. The FIR filter includes a first memory, a multiplier, and an accumulation module. For each input sample of the digital input signal, the first memory provides N/D corresponding tap coefficients from a plurality of tap coefficients in turn. The multiplier multiplies the input sample with the N/D corresponding tap coefficients in turn to generate N/D product values. The accumulation module adds the N/D product values to N/D previous accumulation values to generate N/D renewed accumulation values respectively. If one of the accumulation values has already accumulated N product values, the accumulation module outputs the accumulation value as an output sample of the digital output signal.
摘要:
The invention discloses a finite impulse response (FIR) filter for processing a digital input signal to generate a digital output signal. The FIR filter has a tap amount N and a decimation ratio D. The FIR filter includes a first memory, a multiplier, and an accumulation module. For each input sample of the digital input signal, the first memory provides N/D corresponding tap coefficients from a plurality of tap coefficients in turn. The multiplier multiplies the input sample with the N/D corresponding tap coefficients in turn to generate N/D product values. The accumulation module adds the N/D product values to N/D previous accumulation values to generate N/D renewed accumulation values respectively. If one of the accumulation values has already accumulated N product values, the accumulation module outputs the accumulation value as an output sample of the digital output signal.