Receiver apparatus

A receiver apparatus is provided. The apparatus includes a single field effect transistor mixer comprising a gate, a source and a drain, wherein one of the source or the drain is configured to receive a first signal from a first low noise amplifier at a receiving frequency and another of the source or the drain is configured to output a second signal at an intermediate frequency to a second low noise amplifier; and a local oscillator configured to apply a third signal to the gate.

INTRODUCTION

Apparatuses consistent with exemplary embodiments relate to receivers. More particularly, apparatuses consistent with exemplary embodiments relate to the architecture of receivers of a radar signal.

SUMMARY

One or more exemplary embodiments provide a receiving apparatus. More particularly, one or more exemplary embodiments provide a receiving apparatus with single field effect transistor mixer configured to convert a signal received at a receiving frequency to an intermediate frequency.

According to an aspect of an exemplary embodiment, a receiver apparatus is provided. The apparatus includes a transconductance mixer including a gate, a source and a drain, wherein the source is configured to receive a first signal from a first low noise amplifier at a receiving frequency and the drain is configured to output a second signal at an intermediate frequency to a second low noise amplifier; and a local oscillator configured to apply a third signal to the gate. The local oscillator may include a signal driver configured to drive a driver signal, a multiplier configured to receive the driver signal output by the signal driver, multiply the signal, and output a multiplied signal, a differential to single ended transformer configured to receive the multiplied signal, transform the multiplied signal, and output a transformed signal, a gain amplifier configured to receive the transformed signal, amplify the transformed signal, and output the gain amplified signal, and a filter including a notch filter and a bandpass filter, the filter configured to receive the gain amplified signal, filter the gain amplified signal to reject out-of-band harmonics and noise, and output a filtered signal as the third signal to the gate.

The signal driver may include a micrometer or millimeter wave source at a frequency of ‘f.’

The multiplier may be a push-pull multiplier.

The transconductance mixer may be a single field effect transistor-based mixer.

The filter may include a parallel coupled transmission line filter or a quarter wave transformer.

The notch filter may an f*(n−m) filter, where ‘f’ is the frequency of signal driver, m is a frequency multiplier corresponding to the multiplier of the local oscillator, and n is frequency multiplier corresponding to the receiving frequency.

The bandpass filter may be an f*(m) filter, where ‘f’ is the frequency of signal driver and m is a frequency multiplier corresponding to the multiplier of the local oscillator.

The first low noise amplifier and the second low noise amplifier may be single ended low noise amplifiers.

The local oscillator may be configured to apply the third signal of 160 GHz to the gate.

The signal driver may be configured to drive the driver signal at 20 GHz.

The multiplier may be an 8× multiplier

The differential to single ended transformer may be a 160 GHz transformer

The gain amplifier may be a 160 GHz single ended power amplifier.

The notch filter may be an 80 GHz notch filter and the bandpass filter may include a quarter wave transformer.

The input stage of the apparatus, which is a part of the matching network, may include a shorted stub to protect downstream devices from electrostatic discharge.

The differential to single ended transformer may be implemented with an inverted micro-strip.

The apparatus may include signal lines implemented with micro-coax.

According to an aspect of another exemplary embodiment, a receiver apparatus is provided. The apparatus includes a single field effect transistor mixer including a gate, a source and a drain, wherein one of the source or the drain is configured to receive a first signal from a first low noise amplifier at a receiving frequency and another of the source or the drain is configured to output a second signal at an intermediate frequency to a second low noise amplifier; and a local oscillator configured to apply a third signal to the gate.

The first low noise amplifier and the second low noise amplifier may be single ended low noise amplifiers.

The receiving frequency of the first signal may be ‘f’*n, the intermediate frequency of the second signal may be ‘f’*(n−m), and the frequency of third signal may be f’*(m), where f is the frequency, ‘n’ and ‘m’ are constant values.

Other objects, advantages and novel features of the exemplary embodiments will become more apparent from the following detailed description of exemplary embodiments and the accompanying drawings.

DETAILED DESCRIPTION

A receiving apparatus will now be described in detail with reference toFIGS. 1-3of the accompanying drawings in which like reference numerals refer to like elements throughout.

The following disclosure will enable one skilled in the art to practice the inventive concept. However, the exemplary embodiments disclosed herein are merely exemplary and do not limit the inventive concept to exemplary embodiments described herein. Moreover, descriptions of features or aspects of each exemplary embodiment should typically be considered as available for aspects of other exemplary embodiments.

It is also understood that where it is stated herein that a first element is “connected to,” “attached to,” “formed on,” or “disposed on” a second element, the first element may be connected directly to, formed directly on or disposed directly on the second element or there may be intervening elements between the first element and the second element, unless it is stated that a first element is “directly” connected to, attached to, formed on, or disposed on the second element. In addition, if a first element is configured to “send” or “receive” information from a second element, the first element may send or receive the information directly to or from the second element, send or receive the information via a bus, send or receive the information via a network, or send or receive the information via intermediate elements, unless the first element is indicated to send or receive information “directly” to or from the second element.

Throughout the disclosure, one or more of the elements disclosed may be combined into a single device or combined into one or more devices. In addition, individual elements may be provided on separate devices.

Vehicles such as passenger cars, motorcycles, trucks, sports utility vehicles (SUVs), recreational vehicles (RVs), marine vessels, aircraft, etc., are being equipped with radar devices configured to detect objects around the vehicle. The detection and tracking of objects may be used in autonomous vehicle system applications as well as advanced safety systems.

Radars may function at many different frequencies. For example, high-resolution imaging in radars can be achieved by increasing radar operation frequency. One type of radar used in automotive applications is a 77 GHz radar, that may include a system-on-chip. This system on chip radar may be leveraged to implement a higher frequency radar by up converting and amplifying the radar frequency. However, there may be issues in that the increase of operation frequency may degrade transmission power, most receivers are based on differential and balanced mixer architecture, and there may be leakage of the sub-harmonic of a local oscillator (LO) into the intermediate frequency (IF). A receiving apparatus with coherent local LO based receiver architecture design to leverage the system on chip radar by upconverting the 77 GHz radar signal, according to exemplary embodiment, addresses the aforementioned issues.

FIG. 1shows a schematic of the architecture of the receiving apparatus100according to an exemplary embodiment. As shown inFIG. 1, one or more of the receiver apparatus100may be on a vehicle110and connected to a plurality of antennas130. The receiver apparatus100may include a transconductance mixer125. The transconductance mixer125may include a source or drain configured to receive a first signal101at a reception or receiving frequency (RF)101and a drain or source configured to output a second signal102at an intermediate frequency. A single ended low noise amplifier105may be configured to receive the first signal101at a reception or receiving frequency101and output the signal to the source or drain. Another single ended low noise amplifier115may be configured to receive the second signal102at the intermediate frequency from the drain or source and output the second signal102to the system on chip radar.

The gate of the transconductance mixer125may be connected to a local oscillator (LO)120that applies a signal to the gate. The LO may include one or more from among a source signal driver121, a multiplier122, a transformer123, an amplifier124and a filter126. In one example, the LO may be configured to apply a 160 GHz or 154 GHz signal to the gate.

The signal driver121may be configured to drive a driver signal. The signal driver may be a micrometer or millimeter wave source. In one example, the signal driver121may be configured to drive the driver signal at 20 GHz or a 19.25 GHz signal.

The multiplier122may be configured to receive the driver signal output by the signal driver121, multiply the driver signal, and output a multiplied signal. The multiplier may be a push-pull multiplier and, in one example, the multiplier may be an 8× multiplier.

The transformer123may be a differential to single ended transformer configured to receive the multiplied signal, transform the multiplied signal, and output a transformed signal. In one example, the differential to single ended transformer may be a 160 GHz or 154 GHz transformer. In another example, the differential to single ended transformer may be implemented with an inverted micro-strip.

The amplifier124may be a gain amplifier configured to receive the transformed signal, amplify the transformed signal, and output the gain amplified signal. The transconductance mixer125may be a single field effect transistor-based mixer or a microwave mixer.

The filter126may include a notch filter and a bandpass filter. The filter126may be configured to receive the gain amplified signal, filter the gain amplified signal, and output a filtered signal as the third signal to the gate. The bandpass filter may filter to output an f*(m) signal, where ‘f’ is the frequency of signal driver and m is a frequency multiplier corresponding to the multiplier of the local oscillator. The notch filter may filter to output an f*(n−m) signal, where ‘f’ is the frequency of signal driver, m is a frequency multiplier corresponding to the multiplier of the local oscillator, and n is frequency multiplier corresponding to the receiving frequency. In one example, the notch filter may be an 80 GHz notch filter and the bandpass filter may include a quarter wave transformer or a transmission line filter. The filter may be configured to filter the gain amplified signal to reject out-of-band harmonics and noise.

FIGS. 2A-2Bshow radio frequency properties of the receiving apparatus according to aspects of an exemplary embodiment.

Referring toFIG. 2A, a receiver apparatus200is shown. The receiver apparatus may include a transconductance mixer205. The transconductance mixer205may include a source configured to receive a first signal202at a reception or receiving frequency101through a single ended low noise amplifier202. The transconductance mixer205may also include a drain configured to output a second signal203at an intermediate frequency to another single ended low noise amplifier206. The gate of the transconductance mixer205may be connected to a local oscillator (LO)201that applies a signal to the gate.

The radio frequency properties of the receiver apparatus200are shown in table210. For example, a conversation gain211may be in the range221of 16-17 dB. The NF212may be 12 dB. The Γ_RF213may be less than −15 dB, the Γ_IF214may be less than −18 dB, the Γ_LO215may be less than −19 dB, and power of the LO216may be around 3 dBm.

Referring toFIG. 2B, a first graph230shows the conversion gain232of the receiving frequency231. A second graph240shows the reflection coefficient242at specific frequencies241of the IF signal243, the RF signal245, and the LO signal244.

FIG. 3shows a schematic of the architecture of a 160 GHz local oscillator of the receiving apparatus according to an aspect of an exemplary embodiment.

Referring toFIG. 3, the 160 GHz local oscillator300may include a signal driver310that may be configured to drive the driver signal at 20 GHz and output the driver signal to a multiplier320. The multiplier320may be an 8× push-pull multiplier and be configured to output a signal to a 160 GHz differential to single ended transformer330. The transformer330may be configured to output a transformed signal to a 160 GHz LO power gain amplifier340, which amplifies and outputs the gain amplified signal to filter350. The filter350may be an 80 GHz notch filter with quarter wave transformer configured to filter the signal and output the LO signal to the mixer gate.

One or more exemplary embodiments have been described above with reference to the drawings. The exemplary embodiments described above should be considered in a descriptive sense only and not for purposes of limitation. Moreover, the exemplary embodiments may be modified without departing from the spirit and scope of the inventive concept, which is defined by the following claims.