A zero intermediate frequencyRFtransceiver with tunable operating frequency band

Abstract

A zero intermediate frequency (zero‐IF) radio frequency (RF) transceiver with tunable operating frequency band is proposed in this article, which consists of a transmitter (Tx), a receiver (Rx). Both the Tx and the Rx can achieve broadband operation. By tuning the carrier signal frequency (fc), the Tx and Rx can work in variable frequency band which is determined by fc. Therefore, a transceiver with tunable operating frequency band was realized. A prototype of the designed transceiver was designed, simulated, manufactured, and measured. In the end, a zero‐IF RF transceiver with tunable frequency band during 2.3 to 3.5 GHz was implemented. The gain range of the Tx is −35 to 28 dB. The gain range of the Rx is 28 to 78 dB. For 16‐QAM signal with a symbol rate of 15 MHz, the error vector magnitude of proposed Tx and Rx are less than 7.8% and 5.0%, respectively.

Pseudolites to Support Location Services in Smart Cities: Review and Prospects

“…Traditionally, the near-far effect may be mitigated by the following [11,101]: (1) transmitting a pulse signal with a fixed period in the GPS band but with frequency offset; this scheme is feasible because by adjusting the carrier signal frequency, the pseudolite can be made to operate in a variable frequency band determined by the signal frequency [102];…”

“…A general pulsing scheme based on random permutations was proposed to mitigate this effect [103]; signal orthogonality can be exploited to counteract the pseudolite signal near-far effect [104]. Traditionally, the near-far effect may be mitigated by the following [11,101]: (1) transmitting a pulse signal with a fixed period in the GPS band but with frequency offset; this scheme is feasible because by adjusting the carrier signal frequency, the pseudolite can be made to operate in a variable frequency band determined by the signal frequency [102];…”

A tunable ultra‐wideband superheterodyne radio frequency receiver with high‐image‐rejection levels

“…In summary, ultra-wideband coverage has become more critical, and ultra-wideband receiving systems have a broader application prospect. At present, the commonly used technical solutions for receiver systems are rough as follows: superheterodyne architecture, [8][9][10][11][12][13][14] zerointermediate frequency (IF) architecture, [15][16] and low-IF architecture. [17][18] The design of this article uses the superheterodyne architecture as the final technical solution.…”