Comparison and Analysis of Wireless Transceiver Chip Solutions

In the wireless data transmission system, the wireless transceiver chip is the core carrier of the technology. As the signal sending and receiving, modulation, and debugging, it plays an absolute core role. We will compare and analyze several Wireless Transceiver Chip Solutions.

1) CC1000 Wireless Transceiver Chip Solution

CC1000 is a single-chip programmable RF transceiver chip launched by Chipcon. Based on Chipcon's Smart RF technology, CC1000 can work in the ISM band (MHz ~ 1000 MHz ). CCl000 integrates multiple functions such as RF transmitting, RF receiving, PLL synthesis, PSK modulation and demodulation, and programmable control. The CCl000 uses the phase-locked loop technology. The emission frequency is configured through the internal frequency synthesizer, And the configurable range is MHz ~ 1000 MHz, suitable for the application of Frequency Hopping protocol, generally can be configured with 10 or 20 frequency points, the chip sensitivity is-109 dBm, and can be automatically calibrated, programmable output power is-20 dBm ~ + 10 dBm, with a communication rate of 78.6 Kbps. The main operating parameters of CCl000 can be programmed by a serial interface, which is convenient to use and flexible. There are few peripheral components on the CCl000 chip and there is little requirement for accuracy. Three encoding methods are provided to interface with the microcontroller. Therefore, CCl000 and a microcontroller and a few external components can form a complete RF receiving and receiving system. However, it has a disadvantage that it cannot be directly connected to the serial port of a single-chip microcomputer. The data needs to be encoded in Manchester, which is less efficient.

Ii) nRF903 Wireless Transceiver Chip Solution

NRF903 is a single-chip ultra-high frequency multi-segment wireless transceiver chip designed for the 433/868/915 MHz ISM band by Nordic. It adopts the optimized GFSK modulation and demodulation technology and has high anti-interference ability, using the DDS + PLL frequency synthesis technology, the frequency stability is good, the sensitivity is as high as-l04 dBm, the transmit power can be adjusted, the maximum transmit power is + l0 dBrn, data with a maximum bandwidth of 155.6 bps can be transmitted at 76.8 kHz. The operating voltage range of nRF903 can be from 2.7V ~ 3.3 V, the consumption of the standby current is 600 laA, and the consumption of the low-power mode current is only 1 uA, which can meet the requirements of low-power devices. The nRF903 has multiple channels (a maximum of 170 channels). It is suitable for the use of frequency hopping protocol in special scenarios that require multi-channel operations.

The antenna interface of nRF903 is designed as a differential antenna to facilitate the use of low-cost PCB antennas, all parameters, including the operating frequency and transmit power, can be set with a serial line (CS, CFG-CLK, and CFG-DATA) through a 14-bit configuration register. The internal structure of nRF903 can be divided into transmission circuit, receiving circuit, mode and low-power control logic circuit and serial interface. The transmitting circuit includes RF power amplifier, PLL, VCO, and frequency synthesizer. The baseline oscillator uses an external crystal oscillator to generate the baseline frequency required for the circuit. The oscillator consists of a Frequency Synthesizer Based on DDS, an external passive loop filter, and a voltage controlled oscillator. A voltage controlled oscillator consists of an On-chip oscillator circuit and an external LC resonant circuit. DATA to be transmitted is input through the DATA end. The receiving circuit includes low noise amplifier, mixer, intermediate frequency amplifier, GFSK modem, and filter. Low-noise amplifier amplified input RF signal.

3) nRF401 Wireless Transceiver Chip Solution

NRF401 is a single-chip UHF radio transceiver chip developed by Nordic, working in the 433 MHz ISM (Industrial, Scientific and Medical) band. It adopts the PSK modulation and demodulation technology, has strong anti-interference ability, and uses the PLL frequency synthesis technology. It has good frequency stability, a maximum transmit power of 10 dBm, and a maximum receiving sensitivity of-105 dBm, the data transmission rate can reach 20 Kbps, and the operating voltage is + 3 V ~ Between 5 V. The nRF401 wireless transceiver chip requires fewer peripheral components and can be directly connected to the single-chip serial port. The nRF401 chip package contains transmit power amplifier (PA), low noise receiving amplifier (LNA), crystal oscillator (OSC), PLL, VCO, and MIXFR) and describe (DEM. In the receiving mode, the nRF401 is configured as a traditional external receiver, and the digital signal of the received RF modulation is amplified by the low noise amplifier, and transformed into an intermediate frequency by the mixer, after amplification and filtering, the system enters the modem. After demodulation, it is transformed into a digital signal output (DOUT) end. In the transmit mode, the digital signal is input at the DIN end, And the RF output of the kfq transmit power amplifier is performed after the phase-locked loop and the voltage controlled oscillator are processed. Due to the use of crystal oscillation and PLL synthesis techniques, the frequency stability is extremely good; the use of the PSK modulation and decoding, strong anti-interference ability.

4) comprehensive comparative analysis

Compare the above solutions, considering the portability, efficiency and cost of the system. Although solution 1 can meet the design requirements and has few peripheral components, it cannot be directly connected to the single-chip microcomputer serial port for use. The data needs to be encoded in Manchester, which greatly reduces the efficiency of use; solution 2 is an ideal chip, but considering that the operating voltage must be the same as the operating voltage of the single chip microcomputer AT89S52, this solution is not selected. Solution 3 is more suitable for the requirements of this design. Therefore, solution 3 is used to implement this system.